HBASE-19114 Split out o.a.h.h.zookeeper from hbase-server and hbase-client

- Moved DrainingServerTracker and RegionServerTracker to hbase-server:o.a.h.h.master.
- Moved SplitOrMergeTracker to oahh.master (because it depends on a PB)
- Moving hbase-client:oahh.zookeeper.*  to hbase-zookeeper module.  After HBASE-19200, hbase-client doesn't need them anymore (except 3 classes).
- Renamed some classes to use a consistent naming for classes - ZK instead of mix of ZK, Zk , ZooKeeper. Couldn't rename following public classes: MiniZooKeeperCluster, ZooKeeperConnectionException. Left RecoverableZooKeeper for lack of better name. (suggestions?)
- Sadly, can't move tests out because they depend on HBaseTestingUtility (which defeats part of the purpose - trimming down hbase-server tests. We need to promote more use of mocks in our tests)

bin/hbase

@@ -17,7 +17,7 @@
 # * See the License for the specific language governing permissions and
 # * limitations under the License.
 # */
-# 
+#
 # The hbase command script.  Based on the hadoop command script putting
 # in hbase classes, libs and configurations ahead of hadoop's.
 #
@@ -91,10 +91,10 @@ if [ $# = 0 ]; then
   echo "  hfile           Store file analyzer"
   echo "  zkcli           Run the ZooKeeper shell"
   echo "  master          Run an HBase HMaster node"
-  echo "  regionserver    Run an HBase HRegionServer node" 
+  echo "  regionserver    Run an HBase HRegionServer node"
   echo "  zookeeper       Run a ZooKeeper server"
-  echo "  rest            Run an HBase REST server" 
+  echo "  rest            Run an HBase REST server"
-  echo "  thrift          Run the HBase Thrift server" 
+  echo "  thrift          Run the HBase Thrift server"
   echo "  thrift2         Run the HBase Thrift2 server"
   echo "  clean           Run the HBase clean up script"
   echo "  classpath       Dump hbase CLASSPATH"
@@ -274,7 +274,7 @@ fi
 if $cygwin; then
   JAVA_LIBRARY_PATH=`cygpath -p "$JAVA_LIBRARY_PATH"`
 fi
- 
+
 # restore ordinary behaviour
 unset IFS
 
@@ -362,7 +362,7 @@ elif [ "$COMMAND" = "wal" ] ; then
 elif [ "$COMMAND" = "hfile" ] ; then
   CLASS='org.apache.hadoop.hbase.io.hfile.HFilePrettyPrinter'
 elif [ "$COMMAND" = "zkcli" ] ; then
-  CLASS="org.apache.hadoop.hbase.zookeeper.ZooKeeperMainServer"
+  CLASS="org.apache.hadoop.hbase.zookeeper.ZKMainServer"
 elif [ "$COMMAND" = "backup" ] ; then
   CLASS='org.apache.hadoop.hbase.backup.BackupDriver'
 elif [ "$COMMAND" = "restore" ] ; then
@@ -422,7 +422,7 @@ elif [ "$COMMAND" = "zookeeper" ] ; then
   fi
 elif [ "$COMMAND" = "clean" ] ; then
   case $1 in
-    --cleanZk|--cleanHdfs|--cleanAll) 
+    --cleanZk|--cleanHdfs|--cleanAll)
       matches="yes" ;;
     *) ;;
   esac

bin/hbase.cmd

@@ -16,7 +16,7 @@
 @rem * See the License for the specific language governing permissions and
 @rem * limitations under the License.
 @rem */
-@rem 
+@rem
 @rem The hbase command script.  Based on the hadoop command script putting
 @rem in hbase classes, libs and configurations ahead of hadoop's.
 @rem
@@ -197,7 +197,7 @@ if exist "%HBASE_HOME%\build\native" (
 rem This loop would set %hbase-command-arguments%
 set _hbasearguments=
 :MakeCmdArgsLoop
-  if [%1]==[] goto :EndLoop 
+  if [%1]==[] goto :EndLoop
 
   if not defined _hbasearguments (
     set _hbasearguments=%1
@@ -205,8 +205,8 @@ set _hbasearguments=
     set _hbasearguments=!_hbasearguments! %1
   )
   shift
-goto :MakeCmdArgsLoop 
+goto :MakeCmdArgsLoop
-:EndLoop 
+:EndLoop
 
 set hbase-command-arguments=%_hbasearguments%
 
@@ -424,7 +424,7 @@ goto :eof
   goto :eof
 
 :zkcli
-  set CLASS=org.apache.hadoop.hbase.zookeeper.ZooKeeperMainServer
+  set CLASS=org.apache.hadoop.hbase.zookeeper.ZKMainServer
   goto :eof
 
 :mapredcp

conf/log4j.properties

@@ -98,7 +98,7 @@ log4j.logger.org.apache.hadoop.hbase=INFO
 log4j.logger.org.apache.hadoop.hbase.META=INFO
 # Make these two classes INFO-level. Make them DEBUG to see more zk debug.
 log4j.logger.org.apache.hadoop.hbase.zookeeper.ZKUtil=INFO
-log4j.logger.org.apache.hadoop.hbase.zookeeper.ZooKeeperWatcher=INFO
+log4j.logger.org.apache.hadoop.hbase.zookeeper.ZKWatcher=INFO
 #log4j.logger.org.apache.hadoop.dfs=DEBUG
 # Set this class to log INFO only otherwise its OTT
 # Enable this to get detailed connection error/retry logging.

hbase-archetypes/hbase-client-project/src/main/resources/log4j.properties

@@ -95,7 +95,7 @@ log4j.logger.org.apache.zookeeper=INFO
 log4j.logger.org.apache.hadoop.hbase=INFO
 # Make these two classes INFO-level. Make them DEBUG to see more zk debug.
 log4j.logger.org.apache.hadoop.hbase.zookeeper.ZKUtil=INFO
-log4j.logger.org.apache.hadoop.hbase.zookeeper.ZooKeeperWatcher=INFO
+log4j.logger.org.apache.hadoop.hbase.zookeeper.ZKWatcher=INFO
 #log4j.logger.org.apache.hadoop.dfs=DEBUG
 # Set this class to log INFO only otherwise its OTT
 # Enable this to get detailed connection error/retry logging.

hbase-archetypes/hbase-shaded-client-project/src/main/resources/log4j.properties

@@ -95,7 +95,7 @@ log4j.logger.org.apache.zookeeper=INFO
 log4j.logger.org.apache.hadoop.hbase=INFO
 # Make these two classes INFO-level. Make them DEBUG to see more zk debug.
 log4j.logger.org.apache.hadoop.hbase.zookeeper.ZKUtil=INFO
-log4j.logger.org.apache.hadoop.hbase.zookeeper.ZooKeeperWatcher=INFO
+log4j.logger.org.apache.hadoop.hbase.zookeeper.ZKWatcher=INFO
 #log4j.logger.org.apache.hadoop.dfs=DEBUG
 # Set this class to log INFO only otherwise its OTT
 # Enable this to get detailed connection error/retry logging.

hbase-assembly/pom.xml

@@ -278,6 +278,10 @@
       <groupId>org.apache.hbase</groupId>
       <artifactId>hbase-examples</artifactId>
     </dependency>
+    <dependency>
+      <groupId>org.apache.hbase</groupId>
+      <artifactId>hbase-zookeeper</artifactId>
+    </dependency>
   </dependencies>
   <profiles>
     <profile>

hbase-assembly/src/main/assembly/hadoop-two-compat.xml

@@ -56,6 +56,7 @@
         <include>org.apache.hbase:hbase-shell</include>
         <include>org.apache.hbase:hbase-testing-util</include>
         <include>org.apache.hbase:hbase-thrift</include>
+        <include>org.apache.hbase:hbase-zookeeper</include>
       </includes>
       <!-- Binaries for the dependencies also go in the hbase-jars directory -->
       <binaries>

hbase-it/src/test/java/org/apache/hadoop/hbase/IntegrationTestMetaReplicas.java

@@ -27,8 +27,8 @@ import org.apache.hadoop.hbase.protobuf.ProtobufUtil;
 import org.apache.hadoop.hbase.regionserver.StorefileRefresherChore;
 import org.apache.hadoop.hbase.testclassification.IntegrationTests;
 import org.apache.hadoop.hbase.zookeeper.ZKUtil;
+import org.apache.hadoop.hbase.zookeeper.ZKWatcher;
 import org.apache.hadoop.hbase.zookeeper.ZNodePaths;
-import org.apache.hadoop.hbase.zookeeper.ZooKeeperWatcher;
 import org.junit.AfterClass;
 import org.junit.BeforeClass;
 import org.junit.Test;
@@ -37,7 +37,7 @@ import org.junit.experimental.categories.Category;
 /**
  * An integration test that starts the cluster with three replicas for the meta
  * It then creates a table, flushes the meta, kills the server holding the primary.
- * After that a client issues put/get requests on the created table - the other 
+ * After that a client issues put/get requests on the created table - the other
  * replicas of the meta would be used to get the location of the region of the created
  * table.
  */
@@ -60,7 +60,7 @@ public class IntegrationTestMetaReplicas {
         StorefileRefresherChore.REGIONSERVER_STOREFILE_REFRESH_PERIOD, 1000);
     // Make sure there are three servers.
     util.initializeCluster(3);
-    ZooKeeperWatcher zkw = util.getZooKeeperWatcher();
+    ZKWatcher zkw = util.getZooKeeperWatcher();
     Configuration conf = util.getConfiguration();
     String baseZNode = conf.get(HConstants.ZOOKEEPER_ZNODE_PARENT,
         HConstants.DEFAULT_ZOOKEEPER_ZNODE_PARENT);

hbase-it/src/test/java/org/apache/hadoop/hbase/test/IntegrationTestZKAndFSPermissions.java

@@ -39,8 +39,8 @@ import org.apache.hadoop.hbase.util.AbstractHBaseTool;
 import org.apache.hadoop.hbase.util.FSUtils;
 import org.apache.hadoop.hbase.zookeeper.RecoverableZooKeeper;
 import org.apache.hadoop.hbase.zookeeper.ZKUtil;
+import org.apache.hadoop.hbase.zookeeper.ZKWatcher;
 import org.apache.hadoop.hbase.zookeeper.ZNodePaths;
-import org.apache.hadoop.hbase.zookeeper.ZooKeeperWatcher;
 import org.apache.hadoop.util.ToolRunner;
 import org.apache.zookeeper.KeeperException;
 import org.apache.zookeeper.KeeperException.Code;
@@ -139,7 +139,7 @@ public class IntegrationTestZKAndFSPermissions extends AbstractHBaseTool {
 
   private void testZNodeACLs() throws IOException, KeeperException, InterruptedException {
 
-    ZooKeeperWatcher watcher = new ZooKeeperWatcher(conf, "IntegrationTestZnodeACLs", null);
+    ZKWatcher watcher = new ZKWatcher(conf, "IntegrationTestZnodeACLs", null);
     RecoverableZooKeeper zk = ZKUtil.connect(this.conf, watcher);
 
     String baseZNode = watcher.znodePaths.baseZNode;
@@ -155,7 +155,7 @@ public class IntegrationTestZKAndFSPermissions extends AbstractHBaseTool {
     LOG.info("Checking ZK permissions: SUCCESS");
   }
 
-  private void checkZnodePermsRecursive(ZooKeeperWatcher watcher,
+  private void checkZnodePermsRecursive(ZKWatcher watcher,
       RecoverableZooKeeper zk, String znode) throws KeeperException, InterruptedException {
 
     boolean expectedWorldReadable = watcher.isClientReadable(znode);
@@ -201,7 +201,7 @@ public class IntegrationTestZKAndFSPermissions extends AbstractHBaseTool {
         assertTrue(expectedWorldReadable);
         // assert that anyone can only read
         assertEquals(perms, Perms.READ);
-      } else if (superUsers != null && ZooKeeperWatcher.isSuperUserId(superUsers, id)) {
+      } else if (superUsers != null && ZKWatcher.isSuperUserId(superUsers, id)) {
         // assert that super user has all the permissions
         assertEquals(perms, Perms.ALL);
       } else if (new Id("sasl", masterPrincipal).equals(id)) {

hbase-mapreduce/src/main/java/org/apache/hadoop/hbase/mapreduce/Import.java

@@ -48,6 +48,7 @@ import org.apache.hadoop.hbase.KeyValue;
 import org.apache.hadoop.hbase.KeyValueUtil;
 import org.apache.hadoop.hbase.TableName;
 import org.apache.hadoop.hbase.ZooKeeperConnectionException;
+import org.apache.hadoop.hbase.zookeeper.ZKWatcher;
 import org.apache.yetus.audience.InterfaceAudience;
 import org.apache.hadoop.hbase.client.Admin;
 import org.apache.hadoop.hbase.client.Connection;
@@ -64,7 +65,6 @@ import org.apache.hadoop.hbase.io.ImmutableBytesWritable;
 import org.apache.hadoop.hbase.util.Bytes;
 import org.apache.hadoop.hbase.util.MapReduceCell;
 import org.apache.hadoop.hbase.zookeeper.ZKClusterId;
-import org.apache.hadoop.hbase.zookeeper.ZooKeeperWatcher;
 import org.apache.hadoop.io.RawComparator;
 import org.apache.hadoop.io.WritableComparable;
 import org.apache.hadoop.io.WritableComparator;
@@ -608,10 +608,10 @@ public class Import extends Configured implements Tool {
         LOG.info("setting WAL durability to default.");
       }
       // TODO: This is kind of ugly doing setup of ZKW just to read the clusterid.
-      ZooKeeperWatcher zkw = null;
+      ZKWatcher zkw = null;
       Exception ex = null;
       try {
-        zkw = new ZooKeeperWatcher(conf, context.getTaskAttemptID().toString(), null);
+        zkw = new ZKWatcher(conf, context.getTaskAttemptID().toString(), null);
         clusterIds = Collections.singletonList(ZKClusterId.getUUIDForCluster(zkw));
       } catch (ZooKeeperConnectionException e) {
         ex = e;

hbase-mapreduce/src/main/java/org/apache/hadoop/hbase/mapreduce/replication/VerifyReplication.java

@@ -57,7 +57,7 @@ import org.apache.hadoop.hbase.util.Bytes;
 import org.apache.hadoop.hbase.util.FSUtils;
 import org.apache.hadoop.hbase.util.Pair;
 import org.apache.hadoop.hbase.util.Threads;
-import org.apache.hadoop.hbase.zookeeper.ZooKeeperWatcher;
+import org.apache.hadoop.hbase.zookeeper.ZKWatcher;
 import org.apache.hadoop.mapreduce.InputSplit;
 import org.apache.hadoop.mapreduce.Job;
 import org.apache.hadoop.mapreduce.MRJobConfig;
@@ -330,10 +330,10 @@ public class VerifyReplication extends Configured implements Tool {
 
   private static Pair<ReplicationPeerConfig, Configuration> getPeerQuorumConfig(
       final Configuration conf, String peerId) throws IOException {
-    ZooKeeperWatcher localZKW = null;
+    ZKWatcher localZKW = null;
     ReplicationPeerZKImpl peer = null;
     try {
-      localZKW = new ZooKeeperWatcher(conf, "VerifyReplication",
+      localZKW = new ZKWatcher(conf, "VerifyReplication",
           new Abortable() {
             @Override public void abort(String why, Throwable e) {}
             @Override public boolean isAborted() {return false;}

hbase-replication/pom.xml

@@ -130,6 +130,10 @@
       <groupId>org.apache.hbase</groupId>
       <artifactId>hbase-client</artifactId>
     </dependency>
+    <dependency>
+      <groupId>org.apache.hbase</groupId>
+      <artifactId>hbase-zookeeper</artifactId>
+    </dependency>
     <!-- General dependencies -->
     <dependency>
       <groupId>org.apache.commons</groupId>

hbase-replication/src/main/java/org/apache/hadoop/hbase/replication/ReplicationFactory.java

@@ -23,7 +23,7 @@ import org.apache.yetus.audience.InterfaceAudience;
 import org.apache.hadoop.conf.Configuration;
 import org.apache.hadoop.hbase.Abortable;
 import org.apache.hadoop.hbase.Stoppable;
-import org.apache.hadoop.hbase.zookeeper.ZooKeeperWatcher;
+import org.apache.hadoop.hbase.zookeeper.ZKWatcher;
 
 /**
  * A factory class for instantiating replication objects that deal with replication state.
@@ -48,17 +48,17 @@ public class ReplicationFactory {
     return (ReplicationQueuesClient) ConstructorUtils.invokeConstructor(classToBuild, args);
   }
 
-  public static ReplicationPeers getReplicationPeers(final ZooKeeperWatcher zk, Configuration conf,
+  public static ReplicationPeers getReplicationPeers(final ZKWatcher zk, Configuration conf,
-      Abortable abortable) {
+                                                     Abortable abortable) {
     return getReplicationPeers(zk, conf, null, abortable);
   }
 
-  public static ReplicationPeers getReplicationPeers(final ZooKeeperWatcher zk, Configuration conf,
+  public static ReplicationPeers getReplicationPeers(final ZKWatcher zk, Configuration conf,
-      final ReplicationQueuesClient queuesClient, Abortable abortable) {
+                                                     final ReplicationQueuesClient queuesClient, Abortable abortable) {
     return new ReplicationPeersZKImpl(zk, conf, queuesClient, abortable);
   }
 
-  public static ReplicationTracker getReplicationTracker(ZooKeeperWatcher zookeeper,
+  public static ReplicationTracker getReplicationTracker(ZKWatcher zookeeper,
       final ReplicationPeers replicationPeers, Configuration conf, Abortable abortable,
       Stoppable stopper) {
     return new ReplicationTrackerZKImpl(zookeeper, replicationPeers, conf, abortable, stopper);

hbase-replication/src/main/java/org/apache/hadoop/hbase/replication/ReplicationPeerZKImpl.java

@@ -34,9 +34,9 @@ import org.apache.hadoop.hbase.client.replication.ReplicationPeerConfigUtil;
 import org.apache.hadoop.hbase.exceptions.DeserializationException;
 import org.apache.hadoop.hbase.shaded.protobuf.ProtobufUtil;
 import org.apache.hadoop.hbase.shaded.protobuf.generated.ReplicationProtos;
+import org.apache.hadoop.hbase.zookeeper.ZKNodeTracker;
 import org.apache.hadoop.hbase.zookeeper.ZKUtil;
-import org.apache.hadoop.hbase.zookeeper.ZooKeeperNodeTracker;
+import org.apache.hadoop.hbase.zookeeper.ZKWatcher;
-import org.apache.hadoop.hbase.zookeeper.ZooKeeperWatcher;
 import org.apache.yetus.audience.InterfaceAudience;
 import org.apache.zookeeper.KeeperException;
 import org.apache.zookeeper.KeeperException.NodeExistsException;
@@ -62,7 +62,7 @@ public class ReplicationPeerZKImpl extends ReplicationStateZKBase
    * @param id string representation of this peer's identifier
    * @param peerConfig configuration for the replication peer
    */
-  public ReplicationPeerZKImpl(ZooKeeperWatcher zkWatcher, Configuration conf,
+  public ReplicationPeerZKImpl(ZKWatcher zkWatcher, Configuration conf,
                                String id, ReplicationPeerConfig peerConfig,
                                Abortable abortable)
       throws ReplicationException {
@@ -258,9 +258,9 @@ public class ReplicationPeerZKImpl extends ReplicationStateZKBase
   /**
    * Tracker for state of this peer
    */
-  public class PeerStateTracker extends ZooKeeperNodeTracker {
+  public class PeerStateTracker extends ZKNodeTracker {
 
-    public PeerStateTracker(String peerStateZNode, ZooKeeperWatcher watcher,
+    public PeerStateTracker(String peerStateZNode, ZKWatcher watcher,
         Abortable abortable) {
       super(watcher, peerStateZNode, abortable);
     }
@@ -281,11 +281,11 @@ public class ReplicationPeerZKImpl extends ReplicationStateZKBase
   /**
    * Tracker for PeerConfigNode of this peer
    */
-  public class PeerConfigTracker extends ZooKeeperNodeTracker {
+  public class PeerConfigTracker extends ZKNodeTracker {
 
     ReplicationPeerConfigListener listener;
 
-    public PeerConfigTracker(String peerConfigNode, ZooKeeperWatcher watcher,
+    public PeerConfigTracker(String peerConfigNode, ZKWatcher watcher,
         Abortable abortable) {
       super(watcher, peerConfigNode, abortable);
     }

hbase-replication/src/main/java/org/apache/hadoop/hbase/replication/ReplicationPeersZKImpl.java

@@ -43,8 +43,8 @@ import org.apache.hadoop.hbase.util.Pair;
 import org.apache.hadoop.hbase.zookeeper.ZKConfig;
 import org.apache.hadoop.hbase.zookeeper.ZKUtil;
 import org.apache.hadoop.hbase.zookeeper.ZKUtil.ZKUtilOp;
+import org.apache.hadoop.hbase.zookeeper.ZKWatcher;
 import org.apache.hadoop.hbase.zookeeper.ZNodePaths;
-import org.apache.hadoop.hbase.zookeeper.ZooKeeperWatcher;
 import org.apache.yetus.audience.InterfaceAudience;
 import org.apache.zookeeper.KeeperException;
 
@@ -84,8 +84,8 @@ public class ReplicationPeersZKImpl extends ReplicationStateZKBase implements Re
 
   private static final Log LOG = LogFactory.getLog(ReplicationPeersZKImpl.class);
 
-  public ReplicationPeersZKImpl(final ZooKeeperWatcher zk, final Configuration conf,
+  public ReplicationPeersZKImpl(final ZKWatcher zk, final Configuration conf,
-      final ReplicationQueuesClient queuesClient, Abortable abortable) {
+                                final ReplicationQueuesClient queuesClient, Abortable abortable) {
     super(zk, conf, abortable);
     this.abortable = abortable;
     this.peerClusters = new ConcurrentHashMap<>();

hbase-replication/src/main/java/org/apache/hadoop/hbase/replication/ReplicationQueuesArguments.java

@@ -20,8 +20,8 @@ package org.apache.hadoop.hbase.replication;
 
 import org.apache.hadoop.conf.Configuration;
 import org.apache.hadoop.hbase.Abortable;
+import org.apache.hadoop.hbase.zookeeper.ZKWatcher;
 import org.apache.yetus.audience.InterfaceAudience;
-import org.apache.hadoop.hbase.zookeeper.ZooKeeperWatcher;
 
 /**
  * Wrapper around common arguments used to construct ReplicationQueues. Used to construct various
@@ -30,7 +30,7 @@ import org.apache.hadoop.hbase.zookeeper.ZooKeeperWatcher;
 @InterfaceAudience.Private
 public class ReplicationQueuesArguments {
 
-  private ZooKeeperWatcher zk;
+  private ZKWatcher zk;
   private Configuration conf;
   private Abortable abort;
 
@@ -39,16 +39,16 @@ public class ReplicationQueuesArguments {
     this.abort = abort;
   }
 
-  public ReplicationQueuesArguments(Configuration conf, Abortable abort, ZooKeeperWatcher zk) {
+  public ReplicationQueuesArguments(Configuration conf, Abortable abort, ZKWatcher zk) {
     this(conf, abort);
     setZk(zk);
   }
 
-  public ZooKeeperWatcher getZk() {
+  public ZKWatcher getZk() {
     return zk;
   }
 
-  public void setZk(ZooKeeperWatcher zk) {
+  public void setZk(ZKWatcher zk) {
     this.zk = zk;
   }
 

hbase-replication/src/main/java/org/apache/hadoop/hbase/replication/ReplicationQueuesClientArguments.java

@@ -20,8 +20,8 @@ package org.apache.hadoop.hbase.replication;
 
 import org.apache.hadoop.conf.Configuration;
 import org.apache.hadoop.hbase.Abortable;
+import org.apache.hadoop.hbase.zookeeper.ZKWatcher;
 import org.apache.yetus.audience.InterfaceAudience;
-import org.apache.hadoop.hbase.zookeeper.ZooKeeperWatcher;
 
 /**
  * Wrapper around common arguments used to construct ReplicationQueuesClient. Used to construct
@@ -31,7 +31,7 @@ import org.apache.hadoop.hbase.zookeeper.ZooKeeperWatcher;
 @InterfaceAudience.Private
 public class ReplicationQueuesClientArguments extends ReplicationQueuesArguments {
   public ReplicationQueuesClientArguments(Configuration conf, Abortable abort,
-     ZooKeeperWatcher zk) {
+     ZKWatcher zk) {
     super(conf, abort, zk);
   }
   public ReplicationQueuesClientArguments(Configuration conf, Abortable abort) {

hbase-replication/src/main/java/org/apache/hadoop/hbase/replication/ReplicationQueuesClientZKImpl.java

@@ -21,16 +21,16 @@ package org.apache.hadoop.hbase.replication;
 import java.util.List;
 import java.util.Set;
 
-import org.apache.hadoop.hbase.shaded.com.google.common.collect.ImmutableSet;
-import org.apache.hadoop.hbase.shaded.com.google.common.collect.Sets;
 import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
-import org.apache.yetus.audience.InterfaceAudience;
 import org.apache.hadoop.conf.Configuration;
 import org.apache.hadoop.hbase.Abortable;
+import org.apache.hadoop.hbase.shaded.com.google.common.collect.ImmutableSet;
+import org.apache.hadoop.hbase.shaded.com.google.common.collect.Sets;
 import org.apache.hadoop.hbase.zookeeper.ZKUtil;
+import org.apache.hadoop.hbase.zookeeper.ZKWatcher;
 import org.apache.hadoop.hbase.zookeeper.ZNodePaths;
-import org.apache.hadoop.hbase.zookeeper.ZooKeeperWatcher;
+import org.apache.yetus.audience.InterfaceAudience;
 import org.apache.zookeeper.KeeperException;
 import org.apache.zookeeper.data.Stat;
 
@@ -44,8 +44,8 @@ public class ReplicationQueuesClientZKImpl extends ReplicationStateZKBase implem
     this(args.getZk(), args.getConf(), args.getAbortable());
   }
 
-  public ReplicationQueuesClientZKImpl(final ZooKeeperWatcher zk, Configuration conf,
+  public ReplicationQueuesClientZKImpl(final ZKWatcher zk, Configuration conf,
-      Abortable abortable) {
+                                       Abortable abortable) {
     super(zk, conf, abortable);
   }
 

hbase-replication/src/main/java/org/apache/hadoop/hbase/replication/ReplicationQueuesZKImpl.java

@@ -25,20 +25,18 @@ import java.util.TreeSet;
 
 import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
-import org.apache.yetus.audience.InterfaceAudience;
 import org.apache.hadoop.conf.Configuration;
 import org.apache.hadoop.fs.Path;
 import org.apache.hadoop.hbase.Abortable;
 import org.apache.hadoop.hbase.HConstants;
 import org.apache.hadoop.hbase.exceptions.DeserializationException;
-import org.apache.hadoop.hbase.shaded.protobuf.ProtobufUtil;
-import org.apache.hadoop.hbase.shaded.protobuf.generated.ZooKeeperProtos;
 import org.apache.hadoop.hbase.util.Bytes;
 import org.apache.hadoop.hbase.util.Pair;
 import org.apache.hadoop.hbase.zookeeper.ZKUtil;
 import org.apache.hadoop.hbase.zookeeper.ZKUtil.ZKUtilOp;
+import org.apache.hadoop.hbase.zookeeper.ZKWatcher;
 import org.apache.hadoop.hbase.zookeeper.ZNodePaths;
-import org.apache.hadoop.hbase.zookeeper.ZooKeeperWatcher;
+import org.apache.yetus.audience.InterfaceAudience;
 import org.apache.zookeeper.KeeperException;
 
 /**
@@ -75,8 +73,8 @@ public class ReplicationQueuesZKImpl extends ReplicationStateZKBase implements R
     this(args.getZk(), args.getConf(), args.getAbortable());
   }
 
-  public ReplicationQueuesZKImpl(final ZooKeeperWatcher zk, Configuration conf,
+  public ReplicationQueuesZKImpl(final ZKWatcher zk, Configuration conf,
-      Abortable abortable) {
+                                 Abortable abortable) {
     super(zk, conf, abortable);
   }
 

hbase-replication/src/main/java/org/apache/hadoop/hbase/replication/ReplicationStateZKBase.java

@@ -22,21 +22,19 @@ import java.io.ByteArrayOutputStream;
 import java.io.IOException;
 import java.util.List;
 
-import org.apache.hadoop.hbase.shaded.com.google.common.annotations.VisibleForTesting;
-
-import org.apache.hadoop.hbase.shaded.com.google.protobuf.CodedOutputStream;
 import org.apache.hadoop.conf.Configuration;
 import org.apache.hadoop.hbase.Abortable;
-import org.apache.yetus.audience.InterfaceAudience;
+import org.apache.hadoop.hbase.shaded.com.google.common.annotations.VisibleForTesting;
+import org.apache.hadoop.hbase.shaded.com.google.protobuf.CodedOutputStream;
 import org.apache.hadoop.hbase.shaded.protobuf.ProtobufUtil;
 import org.apache.hadoop.hbase.shaded.protobuf.generated.ReplicationProtos;
 import org.apache.hadoop.hbase.zookeeper.ZKConfig;
 import org.apache.hadoop.hbase.zookeeper.ZKUtil;
+import org.apache.hadoop.hbase.zookeeper.ZKWatcher;
 import org.apache.hadoop.hbase.zookeeper.ZNodePaths;
-import org.apache.hadoop.hbase.zookeeper.ZooKeeperWatcher;
+import org.apache.yetus.audience.InterfaceAudience;
 import org.apache.zookeeper.KeeperException;
 
-
 /**
  * This is a base class for maintaining replication state in zookeeper.
  */
@@ -61,7 +59,7 @@ public abstract class ReplicationStateZKBase {
   /** The name of the znode that contains tableCFs */
   protected final String tableCFsNodeName;
 
-  protected final ZooKeeperWatcher zookeeper;
+  protected final ZKWatcher zookeeper;
   protected final Configuration conf;
   protected final Abortable abortable;
 
@@ -74,8 +72,8 @@ public abstract class ReplicationStateZKBase {
       "zookeeper.znode.replication.hfile.refs";
   public static final String ZOOKEEPER_ZNODE_REPLICATION_HFILE_REFS_DEFAULT = "hfile-refs";
 
-  public ReplicationStateZKBase(ZooKeeperWatcher zookeeper, Configuration conf,
+  public ReplicationStateZKBase(ZKWatcher zookeeper, Configuration conf,
-      Abortable abortable) {
+                                Abortable abortable) {
     this.zookeeper = zookeeper;
     this.conf = conf;
     this.abortable = abortable;

hbase-replication/src/main/java/org/apache/hadoop/hbase/replication/ReplicationTrackerZKImpl.java

@@ -24,13 +24,13 @@ import java.util.concurrent.CopyOnWriteArrayList;
 
 import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
+import org.apache.hadoop.hbase.zookeeper.ZKListener;
+import org.apache.hadoop.hbase.zookeeper.ZKWatcher;
 import org.apache.yetus.audience.InterfaceAudience;
 import org.apache.hadoop.conf.Configuration;
 import org.apache.hadoop.hbase.Abortable;
 import org.apache.hadoop.hbase.Stoppable;
 import org.apache.hadoop.hbase.zookeeper.ZKUtil;
-import org.apache.hadoop.hbase.zookeeper.ZooKeeperListener;
-import org.apache.hadoop.hbase.zookeeper.ZooKeeperWatcher;
 import org.apache.zookeeper.KeeperException;
 
 /**
@@ -50,7 +50,7 @@ public class ReplicationTrackerZKImpl extends ReplicationStateZKBase implements
   private final ArrayList<String> otherRegionServers = new ArrayList<>();
   private final ReplicationPeers replicationPeers;
 
-  public ReplicationTrackerZKImpl(ZooKeeperWatcher zookeeper,
+  public ReplicationTrackerZKImpl(ZKWatcher zookeeper,
       final ReplicationPeers replicationPeers, Configuration conf, Abortable abortable,
       Stoppable stopper) {
     super(zookeeper, conf, abortable);
@@ -88,12 +88,12 @@ public class ReplicationTrackerZKImpl extends ReplicationStateZKBase implements
    * Watcher used to be notified of the other region server's death in the local cluster. It
    * initiates the process to transfer the queues if it is able to grab the lock.
    */
-  public class OtherRegionServerWatcher extends ZooKeeperListener {
+  public class OtherRegionServerWatcher extends ZKListener {
 
     /**
      * Construct a ZooKeeper event listener.
      */
-    public OtherRegionServerWatcher(ZooKeeperWatcher watcher) {
+    public OtherRegionServerWatcher(ZKWatcher watcher) {
       super(watcher);
     }
 
@@ -145,12 +145,12 @@ public class ReplicationTrackerZKImpl extends ReplicationStateZKBase implements
   /**
    * Watcher used to follow the creation and deletion of peer clusters.
    */
-  public class PeersWatcher extends ZooKeeperListener {
+  public class PeersWatcher extends ZKListener {
 
     /**
      * Construct a ZooKeeper event listener.
      */
-    public PeersWatcher(ZooKeeperWatcher watcher) {
+    public PeersWatcher(ZKWatcher watcher) {
       super(watcher);
     }
 

hbase-replication/src/main/java/org/apache/hadoop/hbase/replication/TableBasedReplicationQueuesImpl.java

@@ -37,11 +37,10 @@ import org.apache.hadoop.hbase.client.ResultScanner;
 import org.apache.hadoop.hbase.client.RowMutations;
 import org.apache.hadoop.hbase.client.Scan;
 import org.apache.hadoop.hbase.client.Table;
-import org.apache.hadoop.hbase.filter.CompareFilter;
 import org.apache.hadoop.hbase.filter.SingleColumnValueFilter;
 import org.apache.hadoop.hbase.util.Bytes;
 import org.apache.hadoop.hbase.util.Pair;
-import org.apache.hadoop.hbase.zookeeper.ZooKeeperWatcher;
+import org.apache.hadoop.hbase.zookeeper.ZKWatcher;
 import org.apache.zookeeper.KeeperException;
 
 import java.io.IOException;
@@ -77,7 +76,7 @@ public class TableBasedReplicationQueuesImpl extends ReplicationTableBase
     this(args.getConf(), args.getAbortable(), args.getZk());
   }
 
-  public TableBasedReplicationQueuesImpl(Configuration conf, Abortable abort, ZooKeeperWatcher zkw)
+  public TableBasedReplicationQueuesImpl(Configuration conf, Abortable abort, ZKWatcher zkw)
     throws IOException {
     super(conf, abort);
     replicationState = new ReplicationStateZKBase(zkw, conf, abort) {};

hbase-rsgroup/src/main/java/org/apache/hadoop/hbase/rsgroup/RSGroupInfoManagerImpl.java

@@ -77,8 +77,8 @@ import org.apache.hadoop.hbase.regionserver.DisabledRegionSplitPolicy;
 import org.apache.hadoop.hbase.security.access.AccessControlLists;
 import org.apache.hadoop.hbase.util.Bytes;
 import org.apache.hadoop.hbase.zookeeper.ZKUtil;
+import org.apache.hadoop.hbase.zookeeper.ZKWatcher;
 import org.apache.hadoop.hbase.zookeeper.ZNodePaths;
-import org.apache.hadoop.hbase.zookeeper.ZooKeeperWatcher;
 import org.apache.yetus.audience.InterfaceAudience;
 import org.apache.zookeeper.KeeperException;
 
@@ -141,7 +141,7 @@ class RSGroupInfoManagerImpl implements RSGroupInfoManager {
   private final MasterServices masterServices;
   private Table rsGroupTable;
   private final ClusterConnection conn;
-  private final ZooKeeperWatcher watcher;
+  private final ZKWatcher watcher;
   private final RSGroupStartupWorker rsGroupStartupWorker = new RSGroupStartupWorker();
   // contains list of groups that were last flushed to persistent store
   private Set<String> prevRSGroups = new HashSet<>();

hbase-rsgroup/src/test/java/org/apache/hadoop/hbase/rsgroup/VerifyingRSGroupAdminClient.java

@@ -21,6 +21,7 @@ import org.apache.hadoop.hbase.shaded.com.google.common.collect.Maps;
 import org.apache.hadoop.hbase.shaded.com.google.common.collect.Sets;
 import org.apache.hadoop.conf.Configuration;
 import org.apache.hadoop.hbase.TableName;
+import org.apache.hadoop.hbase.zookeeper.ZKWatcher;
 import org.apache.yetus.audience.InterfaceAudience;
 import org.apache.hadoop.hbase.client.ConnectionFactory;
 import org.apache.hadoop.hbase.client.Result;
@@ -32,7 +33,6 @@ import org.apache.hadoop.hbase.protobuf.ProtobufUtil;
 import org.apache.hadoop.hbase.protobuf.generated.RSGroupProtos;
 import org.apache.hadoop.hbase.zookeeper.ZKUtil;
 import org.apache.hadoop.hbase.zookeeper.ZNodePaths;
-import org.apache.hadoop.hbase.zookeeper.ZooKeeperWatcher;
 import org.apache.zookeeper.KeeperException;
 import org.junit.Assert;
 
@@ -45,14 +45,14 @@ import java.util.Set;
 @InterfaceAudience.Private
 public class VerifyingRSGroupAdminClient implements RSGroupAdmin {
   private Table table;
-  private ZooKeeperWatcher zkw;
+  private ZKWatcher zkw;
   private RSGroupAdmin wrapped;
 
   public VerifyingRSGroupAdminClient(RSGroupAdmin RSGroupAdmin, Configuration conf)
       throws IOException {
     wrapped = RSGroupAdmin;
     table = ConnectionFactory.createConnection(conf).getTable(RSGroupInfoManager.RSGROUP_TABLE_NAME);
-    zkw = new ZooKeeperWatcher(conf, this.getClass().getSimpleName(), null);
+    zkw = new ZKWatcher(conf, this.getClass().getSimpleName(), null);
   }
 
   @Override

hbase-server/pom.xml

@@ -388,6 +388,10 @@
       <groupId>org.apache.hbase</groupId>
       <artifactId>hbase-client</artifactId>
     </dependency>
+    <dependency>
+      <groupId>org.apache.hbase</groupId>
+      <artifactId>hbase-zookeeper</artifactId>
+    </dependency>
     <dependency>
       <groupId>org.apache.hbase</groupId>
       <artifactId>hbase-replication</artifactId>

hbase-server/src/main/java/org/apache/hadoop/hbase/Server.java

@@ -23,7 +23,7 @@ import org.apache.hadoop.fs.FileSystem;
 import org.apache.hadoop.hbase.client.ClusterConnection;
 import org.apache.hadoop.hbase.client.Connection;
 import org.apache.hadoop.hbase.zookeeper.MetaTableLocator;
-import org.apache.hadoop.hbase.zookeeper.ZooKeeperWatcher;
+import org.apache.hadoop.hbase.zookeeper.ZKWatcher;
 import org.apache.yetus.audience.InterfaceAudience;
 
 import java.io.IOException;
@@ -43,7 +43,7 @@ public interface Server extends Abortable, Stoppable {
   /**
    * Gets the ZooKeeper instance for this server.
    */
-  ZooKeeperWatcher getZooKeeper();
+  ZKWatcher getZooKeeper();
 
   /**
    * Returns a reference to the servers' connection.

hbase-server/src/main/java/org/apache/hadoop/hbase/ZKNamespaceManager.java

@@ -27,8 +27,8 @@ import org.apache.hadoop.hbase.shaded.protobuf.generated.HBaseProtos;
 import org.apache.hadoop.hbase.util.Bytes;
 import org.apache.hadoop.hbase.zookeeper.ZKUtil;
 import org.apache.hadoop.hbase.zookeeper.ZNodePaths;
-import org.apache.hadoop.hbase.zookeeper.ZooKeeperListener;
+import org.apache.hadoop.hbase.zookeeper.ZKListener;
-import org.apache.hadoop.hbase.zookeeper.ZooKeeperWatcher;
+import org.apache.hadoop.hbase.zookeeper.ZKWatcher;
 import org.apache.zookeeper.KeeperException;
 
 import java.io.IOException;
@@ -48,12 +48,12 @@ import java.util.concurrent.ConcurrentSkipListMap;
  *
  */
 @InterfaceAudience.Private
-public class ZKNamespaceManager extends ZooKeeperListener {
+public class ZKNamespaceManager extends ZKListener {
   private static final Log LOG = LogFactory.getLog(ZKNamespaceManager.class);
   private final String nsZNode;
   private volatile NavigableMap<String,NamespaceDescriptor> cache;
 
-  public ZKNamespaceManager(ZooKeeperWatcher zkw) throws IOException {
+  public ZKNamespaceManager(ZKWatcher zkw) throws IOException {
     super(zkw);
     nsZNode = zkw.znodePaths.namespaceZNode;
     cache = new ConcurrentSkipListMap<>();

hbase-server/src/main/java/org/apache/hadoop/hbase/ZNodeClearer.java

@@ -32,8 +32,8 @@ import org.apache.hadoop.conf.Configuration;
 import org.apache.hadoop.hbase.master.balancer.BaseLoadBalancer;
 import org.apache.hadoop.hbase.zookeeper.MasterAddressTracker;
 import org.apache.hadoop.hbase.zookeeper.ZKUtil;
+import org.apache.hadoop.hbase.zookeeper.ZKWatcher;
 import org.apache.hadoop.hbase.zookeeper.ZNodePaths;
-import org.apache.hadoop.hbase.zookeeper.ZooKeeperWatcher;
 import org.apache.zookeeper.KeeperException;
 
 /**
@@ -132,7 +132,7 @@ public class ZNodeClearer {
    * @param rsZnodePath from HBASE_ZNODE_FILE
    * @return String representation of ServerName or null if fails
    */
-  
+
   public static String parseMasterServerName(String rsZnodePath) {
     String masterServerName = null;
     try {
@@ -141,12 +141,12 @@ public class ZNodeClearer {
     } catch (IndexOutOfBoundsException e) {
       LOG.warn("String " + rsZnodePath + " has wrong format", e);
     }
-    return masterServerName; 
+    return masterServerName;
   }
-  
+
   /**
-   * 
+   *
-   * @return true if cluster is configured with master-rs collocation 
+   * @return true if cluster is configured with master-rs collocation
    */
   private static boolean tablesOnMaster(Configuration conf) {
     boolean tablesOnMaster = true;
@@ -167,9 +167,9 @@ public class ZNodeClearer {
     Configuration tempConf = new Configuration(conf);
     tempConf.setInt("zookeeper.recovery.retry", 0);
 
-    ZooKeeperWatcher zkw;
+    ZKWatcher zkw;
     try {
-      zkw = new ZooKeeperWatcher(tempConf, "clean znode for master",
+      zkw = new ZKWatcher(tempConf, "clean znode for master",
           new Abortable() {
             @Override public void abort(String why, Throwable e) {}
             @Override public boolean isAborted() { return false; }

hbase-server/src/main/java/org/apache/hadoop/hbase/backup/example/HFileArchiveManager.java

@@ -23,12 +23,12 @@ import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
 import org.apache.hadoop.conf.Configuration;
 import org.apache.hadoop.hbase.ZooKeeperConnectionException;
+import org.apache.hadoop.hbase.zookeeper.ZKWatcher;
 import org.apache.yetus.audience.InterfaceAudience;
 import org.apache.hadoop.hbase.client.Connection;
 import org.apache.hadoop.hbase.util.Bytes;
 import org.apache.hadoop.hbase.zookeeper.ZKUtil;
 import org.apache.hadoop.hbase.zookeeper.ZNodePaths;
-import org.apache.hadoop.hbase.zookeeper.ZooKeeperWatcher;
 import org.apache.zookeeper.KeeperException;
 
 /**
@@ -42,12 +42,12 @@ class HFileArchiveManager {
 
   private final String archiveZnode;
   private static final Log LOG = LogFactory.getLog(HFileArchiveManager.class);
-  private final ZooKeeperWatcher zooKeeper;
+  private final ZKWatcher zooKeeper;
   private volatile boolean stopped = false;
 
   public HFileArchiveManager(Connection connection, Configuration conf)
       throws ZooKeeperConnectionException, IOException {
-    this.zooKeeper = new ZooKeeperWatcher(conf, "hfileArchiveManager-on-" + connection.toString(),
+    this.zooKeeper = new ZKWatcher(conf, "hfileArchiveManager-on-" + connection.toString(),
         connection);
     this.archiveZnode = ZKTableArchiveClient.getArchiveZNode(this.zooKeeper.getConfiguration(),
       this.zooKeeper);
@@ -104,7 +104,7 @@ class HFileArchiveManager {
    * @param table table name on which to enable archiving
    * @throws KeeperException
    */
-  private void enable(ZooKeeperWatcher zooKeeper, byte[] table)
+  private void enable(ZKWatcher zooKeeper, byte[] table)
       throws KeeperException {
     LOG.debug("Ensuring archiving znode exists");
     ZKUtil.createAndFailSilent(zooKeeper, archiveZnode);
@@ -123,7 +123,7 @@ class HFileArchiveManager {
    * @param table name of the table to disable
    * @throws KeeperException if an unexpected ZK connection issues occurs
    */
-  private void disable(ZooKeeperWatcher zooKeeper, byte[] table) throws KeeperException {
+  private void disable(ZKWatcher zooKeeper, byte[] table) throws KeeperException {
     // ensure the latest state of the archive node is found
     zooKeeper.sync(archiveZnode);
 

hbase-server/src/main/java/org/apache/hadoop/hbase/backup/example/TableHFileArchiveTracker.java

@@ -22,12 +22,12 @@ import java.util.List;
 
 import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
+import org.apache.hadoop.hbase.zookeeper.ZKWatcher;
 import org.apache.yetus.audience.InterfaceAudience;
 import org.apache.hadoop.conf.Configuration;
 import org.apache.hadoop.hbase.ZooKeeperConnectionException;
 import org.apache.hadoop.hbase.zookeeper.ZKUtil;
-import org.apache.hadoop.hbase.zookeeper.ZooKeeperListener;
+import org.apache.hadoop.hbase.zookeeper.ZKListener;
-import org.apache.hadoop.hbase.zookeeper.ZooKeeperWatcher;
 import org.apache.zookeeper.KeeperException;
 
 /**
@@ -38,14 +38,14 @@ import org.apache.zookeeper.KeeperException;
  * archive.
  */
 @InterfaceAudience.Private
-public class TableHFileArchiveTracker extends ZooKeeperListener {
+public class TableHFileArchiveTracker extends ZKListener {
   private static final Log LOG = LogFactory.getLog(TableHFileArchiveTracker.class);
   public static final String HFILE_ARCHIVE_ZNODE_PARENT = "hfilearchive";
   private HFileArchiveTableMonitor monitor;
   private String archiveHFileZNode;
   private boolean stopped = false;
 
-  private TableHFileArchiveTracker(ZooKeeperWatcher watcher, HFileArchiveTableMonitor monitor) {
+  private TableHFileArchiveTracker(ZKWatcher watcher, HFileArchiveTableMonitor monitor) {
     super(watcher);
     watcher.registerListener(this);
     this.monitor = monitor;
@@ -235,7 +235,7 @@ public class TableHFileArchiveTracker extends ZooKeeperListener {
    */
   public static TableHFileArchiveTracker create(Configuration conf)
       throws ZooKeeperConnectionException, IOException {
-    ZooKeeperWatcher zkw = new ZooKeeperWatcher(conf, "hfileArchiveCleaner", null);
+    ZKWatcher zkw = new ZKWatcher(conf, "hfileArchiveCleaner", null);
     return create(zkw, new HFileArchiveTableMonitor());
   }
 
@@ -247,12 +247,12 @@ public class TableHFileArchiveTracker extends ZooKeeperListener {
    * @return ZooKeeper tracker to monitor for this server if this server should archive hfiles for a
    *         given table
    */
-  private static TableHFileArchiveTracker create(ZooKeeperWatcher zkw,
+  private static TableHFileArchiveTracker create(ZKWatcher zkw,
       HFileArchiveTableMonitor monitor) {
     return new TableHFileArchiveTracker(zkw, monitor);
   }
 
-  public ZooKeeperWatcher getZooKeeperWatcher() {
+  public ZKWatcher getZooKeeperWatcher() {
     return this.watcher;
   }
 

hbase-server/src/main/java/org/apache/hadoop/hbase/backup/example/ZKTableArchiveClient.java

@@ -19,13 +19,13 @@ package org.apache.hadoop.hbase.backup.example;
 
 import java.io.IOException;
 
+import org.apache.hadoop.hbase.zookeeper.ZKWatcher;
 import org.apache.yetus.audience.InterfaceAudience;
 import org.apache.hadoop.conf.Configuration;
 import org.apache.hadoop.conf.Configured;
 import org.apache.hadoop.hbase.client.ClusterConnection;
 import org.apache.hadoop.hbase.util.Bytes;
 import org.apache.hadoop.hbase.zookeeper.ZNodePaths;
-import org.apache.hadoop.hbase.zookeeper.ZooKeeperWatcher;
 import org.apache.zookeeper.KeeperException;
 
 /**
@@ -148,7 +148,7 @@ public class ZKTableArchiveClient extends Configured {
    * @param zooKeeper zookeeper to used for building the full path
    * @return get the znode for long-term archival of a table for
    */
-  public static String getArchiveZNode(Configuration conf, ZooKeeperWatcher zooKeeper) {
+  public static String getArchiveZNode(Configuration conf, ZKWatcher zooKeeper) {
     return ZNodePaths.joinZNode(zooKeeper.znodePaths.baseZNode, conf.get(
       ZOOKEEPER_ZNODE_HFILE_ARCHIVE_KEY, TableHFileArchiveTracker.HFILE_ARCHIVE_ZNODE_PARENT));
   }

hbase-server/src/main/java/org/apache/hadoop/hbase/coordination/ZKSplitLogManagerCoordination.java

@@ -43,12 +43,12 @@ import org.apache.hadoop.hbase.master.SplitLogManager.Task;
 import org.apache.hadoop.hbase.master.SplitLogManager.TerminationStatus;
 import org.apache.hadoop.hbase.util.EnvironmentEdgeManager;
 import org.apache.hadoop.hbase.wal.WALSplitter;
+import org.apache.hadoop.hbase.zookeeper.ZKListener;
 import org.apache.hadoop.hbase.zookeeper.ZKMetadata;
 import org.apache.hadoop.hbase.zookeeper.ZKSplitLog;
 import org.apache.hadoop.hbase.zookeeper.ZKUtil;
+import org.apache.hadoop.hbase.zookeeper.ZKWatcher;
 import org.apache.hadoop.hbase.zookeeper.ZNodePaths;
-import org.apache.hadoop.hbase.zookeeper.ZooKeeperListener;
-import org.apache.hadoop.hbase.zookeeper.ZooKeeperWatcher;
 import org.apache.hadoop.util.StringUtils;
 import org.apache.yetus.audience.InterfaceAudience;
 import org.apache.zookeeper.AsyncCallback;
@@ -65,7 +65,7 @@ import org.apache.hadoop.hbase.shaded.com.google.common.annotations.VisibleForTe
  * {@link SplitLogManagerCoordination}
  */
 @InterfaceAudience.Private
-public class ZKSplitLogManagerCoordination extends ZooKeeperListener implements
+public class ZKSplitLogManagerCoordination extends ZKListener implements
     SplitLogManagerCoordination {
 
   public static final int DEFAULT_TIMEOUT = 120000;
@@ -85,7 +85,7 @@ public class ZKSplitLogManagerCoordination extends ZooKeeperListener implements
 
   public boolean ignoreZKDeleteForTesting = false;
 
-  public ZKSplitLogManagerCoordination(Configuration conf, ZooKeeperWatcher watcher) {
+  public ZKSplitLogManagerCoordination(Configuration conf, ZKWatcher watcher) {
     super(watcher);
     this.conf = conf;
     taskFinisher = new TaskFinisher() {

hbase-server/src/main/java/org/apache/hadoop/hbase/coordination/ZkCoordinatedStateManager.java

@@ -19,17 +19,15 @@ package org.apache.hadoop.hbase.coordination;
 
 import java.io.IOException;
 
-import org.apache.hadoop.conf.Configuration;
 import org.apache.hadoop.hbase.CoordinatedStateManager;
 import org.apache.hadoop.hbase.HBaseInterfaceAudience;
 import org.apache.hadoop.hbase.Server;
-import org.apache.hadoop.hbase.ServerName;
+import org.apache.hadoop.hbase.zookeeper.ZKWatcher;
 import org.apache.yetus.audience.InterfaceAudience;
 import org.apache.hadoop.hbase.procedure.ProcedureCoordinatorRpcs;
 import org.apache.hadoop.hbase.procedure.ProcedureMemberRpcs;
 import org.apache.hadoop.hbase.procedure.ZKProcedureCoordinator;
 import org.apache.hadoop.hbase.procedure.ZKProcedureMemberRpcs;
-import org.apache.hadoop.hbase.zookeeper.ZooKeeperWatcher;
 import org.apache.zookeeper.KeeperException;
 
 /**
@@ -37,7 +35,7 @@ import org.apache.zookeeper.KeeperException;
  */
 @InterfaceAudience.LimitedPrivate(HBaseInterfaceAudience.CONFIG)
 public class ZkCoordinatedStateManager implements CoordinatedStateManager {
-  protected ZooKeeperWatcher watcher;
+  protected ZKWatcher watcher;
   protected SplitLogWorkerCoordination splitLogWorkerCoordination;
   protected SplitLogManagerCoordination splitLogManagerCoordination;
 

hbase-server/src/main/java/org/apache/hadoop/hbase/coordination/ZkSplitLogWorkerCoordination.java

@@ -42,12 +42,12 @@ import org.apache.hadoop.hbase.regionserver.handler.WALSplitterHandler;
 import org.apache.hadoop.hbase.util.CancelableProgressable;
 import org.apache.hadoop.hbase.util.EnvironmentEdgeManager;
 import org.apache.hadoop.hbase.wal.AbstractFSWALProvider;
+import org.apache.hadoop.hbase.zookeeper.ZKListener;
 import org.apache.hadoop.hbase.zookeeper.ZKMetadata;
 import org.apache.hadoop.hbase.zookeeper.ZKSplitLog;
 import org.apache.hadoop.hbase.zookeeper.ZKUtil;
+import org.apache.hadoop.hbase.zookeeper.ZKWatcher;
 import org.apache.hadoop.hbase.zookeeper.ZNodePaths;
-import org.apache.hadoop.hbase.zookeeper.ZooKeeperListener;
-import org.apache.hadoop.hbase.zookeeper.ZooKeeperWatcher;
 import org.apache.hadoop.util.StringUtils;
 import org.apache.yetus.audience.InterfaceAudience;
 import org.apache.zookeeper.AsyncCallback;
@@ -60,7 +60,7 @@ import org.apache.zookeeper.data.Stat;
  *
  */
 @InterfaceAudience.Private
-public class ZkSplitLogWorkerCoordination extends ZooKeeperListener implements
+public class ZkSplitLogWorkerCoordination extends ZKListener implements
     SplitLogWorkerCoordination {
 
   private static final Log LOG = LogFactory.getLog(ZkSplitLogWorkerCoordination.class);
@@ -85,13 +85,13 @@ public class ZkSplitLogWorkerCoordination extends ZooKeeperListener implements
 
   private final ServerName serverName;
 
-  public ZkSplitLogWorkerCoordination(ServerName serverName, ZooKeeperWatcher watcher) {
+  public ZkSplitLogWorkerCoordination(ServerName serverName, ZKWatcher watcher) {
     super(watcher);
     this.serverName = serverName;
   }
 
   /**
-   * Override handler from {@link ZooKeeperListener}
+   * Override handler from {@link ZKListener}
    */
   @Override
   public void nodeChildrenChanged(String path) {
@@ -107,7 +107,7 @@ public class ZkSplitLogWorkerCoordination extends ZooKeeperListener implements
   }
 
   /**
-   * Override handler from {@link ZooKeeperListener}
+   * Override handler from {@link ZKListener}
    */
   @Override
   public void nodeDataChanged(String path) {
@@ -353,7 +353,7 @@ public class ZkSplitLogWorkerCoordination extends ZooKeeperListener implements
    * @param taskZKVersion version of the task in zk
    * @return non-negative integer value when task can be owned by current region server otherwise -1
    */
-  protected static int attemptToOwnTask(boolean isFirstTime, ZooKeeperWatcher zkw,
+  protected static int attemptToOwnTask(boolean isFirstTime, ZKWatcher zkw,
       ServerName server, String task, int taskZKVersion) {
     int latestZKVersion = FAILED_TO_OWN_TASK;
     try {

hbase-server/src/main/java/org/apache/hadoop/hbase/master/ActiveMasterManager.java

@@ -23,6 +23,10 @@ import java.util.concurrent.atomic.AtomicBoolean;
 
 import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
+import org.apache.hadoop.hbase.zookeeper.MasterAddressTracker;
+import org.apache.hadoop.hbase.zookeeper.ZKUtil;
+import org.apache.hadoop.hbase.zookeeper.ZKWatcher;
+import org.apache.hadoop.hbase.zookeeper.ZNodePaths;
 import org.apache.yetus.audience.InterfaceAudience;
 import org.apache.hadoop.hbase.Server;
 import org.apache.hadoop.hbase.ServerName;
@@ -30,11 +34,7 @@ import org.apache.hadoop.hbase.ZNodeClearer;
 import org.apache.hadoop.hbase.exceptions.DeserializationException;
 import org.apache.hadoop.hbase.monitoring.MonitoredTask;
 import org.apache.hadoop.hbase.shaded.protobuf.ProtobufUtil;
-import org.apache.hadoop.hbase.zookeeper.MasterAddressTracker;
+import org.apache.hadoop.hbase.zookeeper.ZKListener;
-import org.apache.hadoop.hbase.zookeeper.ZKUtil;
-import org.apache.hadoop.hbase.zookeeper.ZNodePaths;
-import org.apache.hadoop.hbase.zookeeper.ZooKeeperListener;
-import org.apache.hadoop.hbase.zookeeper.ZooKeeperWatcher;
 import org.apache.zookeeper.KeeperException;
 
 /**
@@ -51,7 +51,7 @@ import org.apache.zookeeper.KeeperException;
  * the active master of the cluster.
  */
 @InterfaceAudience.Private
-public class ActiveMasterManager extends ZooKeeperListener {
+public class ActiveMasterManager extends ZKListener {
   private static final Log LOG = LogFactory.getLog(ActiveMasterManager.class);
 
   final AtomicBoolean clusterHasActiveMaster = new AtomicBoolean(false);
@@ -66,7 +66,7 @@ public class ActiveMasterManager extends ZooKeeperListener {
    * @param sn ServerName
    * @param master In an instance of a Master.
    */
-  ActiveMasterManager(ZooKeeperWatcher watcher, ServerName sn, Server master) {
+  ActiveMasterManager(ZKWatcher watcher, ServerName sn, Server master) {
     super(watcher);
     watcher.registerListener(this);
     this.sn = sn;

hbase-server/src/main/java/org/apache/hadoop/hbase/master/DrainingServerTracker.java

@@ -15,7 +15,7 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
-package org.apache.hadoop.hbase.zookeeper;
+package org.apache.hadoop.hbase.master;
 
 import java.io.IOException;
 import java.util.List;
@@ -24,11 +24,12 @@ import java.util.TreeSet;
 
 import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
+import org.apache.hadoop.hbase.zookeeper.ZKListener;
+import org.apache.hadoop.hbase.zookeeper.ZKUtil;
+import org.apache.hadoop.hbase.zookeeper.ZKWatcher;
 import org.apache.yetus.audience.InterfaceAudience;
 import org.apache.hadoop.hbase.Abortable;
 import org.apache.hadoop.hbase.ServerName;
-import org.apache.hadoop.hbase.master.ServerListener;
-import org.apache.hadoop.hbase.master.ServerManager;
 import org.apache.zookeeper.KeeperException;
 
 /**
@@ -49,14 +50,14 @@ import org.apache.zookeeper.KeeperException;
  *
  */
 @InterfaceAudience.Private
-public class DrainingServerTracker extends ZooKeeperListener {
+public class DrainingServerTracker extends ZKListener {
   private static final Log LOG = LogFactory.getLog(DrainingServerTracker.class);
 
   private ServerManager serverManager;
   private final NavigableSet<ServerName> drainingServers = new TreeSet<>();
   private Abortable abortable;
 
-  public DrainingServerTracker(ZooKeeperWatcher watcher,
+  public DrainingServerTracker(ZKWatcher watcher,
       Abortable abortable, ServerManager serverManager) {
     super(watcher);
     this.abortable = abortable;

hbase-server/src/main/java/org/apache/hadoop/hbase/master/HMaster.java

@@ -18,7 +18,6 @@
  */
 package org.apache.hadoop.hbase.master;
 
-import com.google.common.base.Enums;
 import javax.servlet.ServletException;
 import javax.servlet.http.HttpServlet;
 import javax.servlet.http.HttpServletRequest;
@@ -175,17 +174,14 @@ import org.apache.hadoop.hbase.util.Pair;
 import org.apache.hadoop.hbase.util.Threads;
 import org.apache.hadoop.hbase.util.VersionInfo;
 import org.apache.hadoop.hbase.util.ZKDataMigrator;
-import org.apache.hadoop.hbase.zookeeper.DrainingServerTracker;
 import org.apache.hadoop.hbase.zookeeper.LoadBalancerTracker;
 import org.apache.hadoop.hbase.zookeeper.MasterAddressTracker;
 import org.apache.hadoop.hbase.zookeeper.MasterMaintenanceModeTracker;
 import org.apache.hadoop.hbase.zookeeper.RegionNormalizerTracker;
-import org.apache.hadoop.hbase.zookeeper.RegionServerTracker;
-import org.apache.hadoop.hbase.zookeeper.SplitOrMergeTracker;
 import org.apache.hadoop.hbase.zookeeper.ZKClusterId;
 import org.apache.hadoop.hbase.zookeeper.ZKUtil;
 import org.apache.hadoop.hbase.zookeeper.ZNodePaths;
-import org.apache.hadoop.hbase.zookeeper.ZooKeeperWatcher;
+import org.apache.hadoop.hbase.zookeeper.ZKWatcher;
 import org.apache.yetus.audience.InterfaceAudience;
 import org.apache.zookeeper.KeeperException;
 import org.eclipse.jetty.server.Server;
@@ -2637,7 +2633,7 @@ public class HMaster extends HRegionServer implements MasterServices {
   }
 
   @Override
-  public ZooKeeperWatcher getZooKeeper() {
+  public ZKWatcher getZooKeeper() {
     return zooKeeper;
   }
 

hbase-server/src/main/java/org/apache/hadoop/hbase/master/MasterMetaBootstrap.java

@@ -35,7 +35,7 @@ import org.apache.hadoop.hbase.master.assignment.AssignmentManager;
 import org.apache.hadoop.hbase.monitoring.MonitoredTask;
 import org.apache.hadoop.hbase.zookeeper.MetaTableLocator;
 import org.apache.hadoop.hbase.zookeeper.ZKUtil;
-import org.apache.hadoop.hbase.zookeeper.ZooKeeperWatcher;
+import org.apache.hadoop.hbase.zookeeper.ZKWatcher;
 import org.apache.yetus.audience.InterfaceAudience;
 import org.apache.zookeeper.KeeperException;
 
@@ -85,7 +85,7 @@ public class MasterMetaBootstrap {
   }
 
   private void unassignExcessMetaReplica(int numMetaReplicasConfigured) {
-    final ZooKeeperWatcher zooKeeper = master.getZooKeeper();
+    final ZKWatcher zooKeeper = master.getZooKeeper();
     // unassign the unneeded replicas (for e.g., if the previous master was configured
     // with a replication of 3 and now it is 2, we need to unassign the 1 unneeded replica)
     try {

hbase-server/src/main/java/org/apache/hadoop/hbase/master/MetricsMasterWrapperImpl.java

@@ -29,7 +29,7 @@ import org.apache.hadoop.hbase.TableName;
 import org.apache.yetus.audience.InterfaceAudience;
 import org.apache.hadoop.hbase.quotas.QuotaObserverChore;
 import org.apache.hadoop.hbase.quotas.SpaceQuotaSnapshot;
-import org.apache.hadoop.hbase.zookeeper.ZooKeeperWatcher;
+import org.apache.hadoop.hbase.zookeeper.ZKWatcher;
 
 /**
  * Impl for exposing HMaster Information through JMX
@@ -70,7 +70,7 @@ public class MetricsMasterWrapperImpl implements MetricsMasterWrapper {
 
   @Override
   public String getZookeeperQuorum() {
-    ZooKeeperWatcher zk = master.getZooKeeper();
+    ZKWatcher zk = master.getZooKeeper();
     if (zk == null) {
       return "";
     }
@@ -100,7 +100,7 @@ public class MetricsMasterWrapperImpl implements MetricsMasterWrapper {
     }
     return StringUtils.join(serverManager.getOnlineServers().keySet(), ";");
   }
-  
+
   @Override
   public int getNumRegionServers() {
     ServerManager serverManager = this.master.getServerManager();
@@ -119,7 +119,7 @@ public class MetricsMasterWrapperImpl implements MetricsMasterWrapper {
     return StringUtils.join(serverManager.getDeadServers().copyServerNames(), ";");
   }
 
-  
+
   @Override
   public int getNumDeadRegionServers() {
     ServerManager serverManager = this.master.getServerManager();

hbase-server/src/main/java/org/apache/hadoop/hbase/master/RegionServerTracker.java

@@ -16,7 +16,7 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
-package org.apache.hadoop.hbase.zookeeper;
+package org.apache.hadoop.hbase.master;
 
 import java.io.IOException;
 import java.io.InterruptedIOException;
@@ -28,11 +28,13 @@ import java.util.TreeMap;
 import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
 import org.apache.hadoop.hbase.ServerName;
-import org.apache.yetus.audience.InterfaceAudience;
+import org.apache.hadoop.hbase.zookeeper.ZKListener;
-import org.apache.hadoop.hbase.master.MasterServices;
+import org.apache.hadoop.hbase.zookeeper.ZKUtil;
-import org.apache.hadoop.hbase.master.ServerManager;
+import org.apache.hadoop.hbase.zookeeper.ZKWatcher;
+import org.apache.hadoop.hbase.zookeeper.ZNodePaths;
 import org.apache.hadoop.hbase.shaded.protobuf.ProtobufUtil;
 import org.apache.hadoop.hbase.shaded.protobuf.generated.HBaseProtos.RegionServerInfo;
+import org.apache.yetus.audience.InterfaceAudience;
 import org.apache.zookeeper.KeeperException;
 
 /**
@@ -46,13 +48,13 @@ import org.apache.zookeeper.KeeperException;
  * {@link ServerManager#expireServer(ServerName)}
  */
 @InterfaceAudience.Private
-public class RegionServerTracker extends ZooKeeperListener {
+public class RegionServerTracker extends ZKListener {
   private static final Log LOG = LogFactory.getLog(RegionServerTracker.class);
   private NavigableMap<ServerName, RegionServerInfo> regionServers = new TreeMap<>();
   private ServerManager serverManager;
   private MasterServices server;
 
-  public RegionServerTracker(ZooKeeperWatcher watcher,
+  public RegionServerTracker(ZKWatcher watcher,
       MasterServices server, ServerManager serverManager) {
     super(watcher);
     this.server = server;
@@ -149,7 +151,7 @@ public class RegionServerTracker extends ZooKeeperListener {
   public RegionServerInfo getRegionServerInfo(final ServerName sn) {
     return regionServers.get(sn);
   }
-  
+
   /**
    * Gets the online servers.
    * @return list of online servers

hbase-server/src/main/java/org/apache/hadoop/hbase/master/ServerManager.java

@@ -42,7 +42,6 @@ import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
 import org.apache.hadoop.conf.Configuration;
 import org.apache.hadoop.hbase.ClockOutOfSyncException;
-import org.apache.hadoop.hbase.HBaseIOException;
 import org.apache.hadoop.hbase.HConstants;
 import org.apache.hadoop.hbase.NotServingRegionException;
 import org.apache.hadoop.hbase.RegionLoad;
@@ -59,7 +58,7 @@ import org.apache.hadoop.hbase.monitoring.MonitoredTask;
 import org.apache.hadoop.hbase.regionserver.HRegionServer;
 import org.apache.hadoop.hbase.util.Bytes;
 import org.apache.hadoop.hbase.zookeeper.ZKUtil;
-import org.apache.hadoop.hbase.zookeeper.ZooKeeperWatcher;
+import org.apache.hadoop.hbase.zookeeper.ZKWatcher;
 import org.apache.yetus.audience.InterfaceAudience;
 import org.apache.zookeeper.KeeperException;
 
@@ -507,7 +506,7 @@ public class ServerManager {
   void letRegionServersShutdown() {
     long previousLogTime = 0;
     ServerName sn = master.getServerName();
-    ZooKeeperWatcher zkw = master.getZooKeeper();
+    ZKWatcher zkw = master.getZooKeeper();
     int onlineServersCt;
     while ((onlineServersCt = onlineServers.size()) > 0){
 
@@ -554,7 +553,7 @@ public class ServerManager {
     }
   }
 
-  private List<String> getRegionServersInZK(final ZooKeeperWatcher zkw)
+  private List<String> getRegionServersInZK(final ZKWatcher zkw)
   throws KeeperException {
     return ZKUtil.listChildrenNoWatch(zkw, zkw.znodePaths.rsZNode);
   }

hbase-server/src/main/java/org/apache/hadoop/hbase/master/SplitOrMergeTracker.java

@@ -15,18 +15,22 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
-package org.apache.hadoop.hbase.zookeeper;
+package org.apache.hadoop.hbase.master;
 
 import java.io.IOException;
 
 import org.apache.hadoop.conf.Configuration;
 import org.apache.hadoop.hbase.Abortable;
-import org.apache.yetus.audience.InterfaceAudience;
+import org.apache.hadoop.hbase.zookeeper.ZKNodeTracker;
+import org.apache.hadoop.hbase.zookeeper.ZKUtil;
+import org.apache.hadoop.hbase.zookeeper.ZNodePaths;
+import org.apache.hadoop.hbase.zookeeper.ZKWatcher;
 import org.apache.hadoop.hbase.client.MasterSwitchType;
 import org.apache.hadoop.hbase.exceptions.DeserializationException;
 import org.apache.hadoop.hbase.shaded.protobuf.ProtobufUtil;
 import org.apache.hadoop.hbase.shaded.protobuf.generated.ZooKeeperProtos.SwitchState;
 import org.apache.hadoop.hbase.util.Bytes;
+import org.apache.yetus.audience.InterfaceAudience;
 import org.apache.zookeeper.KeeperException;
 
 
@@ -43,7 +47,7 @@ public class SplitOrMergeTracker {
   private SwitchStateTracker splitStateTracker;
   private SwitchStateTracker mergeStateTracker;
 
-  public SplitOrMergeTracker(ZooKeeperWatcher watcher, Configuration conf,
+  public SplitOrMergeTracker(ZKWatcher watcher, Configuration conf,
                              Abortable abortable) {
     try {
       if (ZKUtil.checkExists(watcher, watcher.znodePaths.switchZNode) < 0) {
@@ -91,9 +95,9 @@ public class SplitOrMergeTracker {
     }
   }
 
-  private static class SwitchStateTracker extends ZooKeeperNodeTracker {
+  private static class SwitchStateTracker extends ZKNodeTracker {
 
-    public SwitchStateTracker(ZooKeeperWatcher watcher, String node, Abortable abortable) {
+    public SwitchStateTracker(ZKWatcher watcher, String node, Abortable abortable) {
       super(watcher, node, abortable);
     }
 

hbase-server/src/main/java/org/apache/hadoop/hbase/master/cleaner/ReplicationZKNodeCleaner.java

@@ -30,6 +30,7 @@ import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
 import org.apache.hadoop.conf.Configuration;
 import org.apache.hadoop.hbase.Abortable;
+import org.apache.hadoop.hbase.zookeeper.ZKWatcher;
 import org.apache.yetus.audience.InterfaceAudience;
 import org.apache.hadoop.hbase.replication.ReplicationFactory;
 import org.apache.hadoop.hbase.replication.ReplicationPeers;
@@ -39,7 +40,6 @@ import org.apache.hadoop.hbase.replication.ReplicationQueuesClientArguments;
 import org.apache.hadoop.hbase.replication.ReplicationStateZKBase;
 import org.apache.hadoop.hbase.zookeeper.ZKUtil;
 import org.apache.hadoop.hbase.zookeeper.ZNodePaths;
-import org.apache.hadoop.hbase.zookeeper.ZooKeeperWatcher;
 import org.apache.zookeeper.KeeperException;
 
 /**
@@ -48,12 +48,12 @@ import org.apache.zookeeper.KeeperException;
 @InterfaceAudience.Private
 public class ReplicationZKNodeCleaner {
   private static final Log LOG = LogFactory.getLog(ReplicationZKNodeCleaner.class);
-  private final ZooKeeperWatcher zkw;
+  private final ZKWatcher zkw;
   private final ReplicationQueuesClient queuesClient;
   private final ReplicationPeers replicationPeers;
   private final ReplicationQueueDeletor queueDeletor;
 
-  public ReplicationZKNodeCleaner(Configuration conf, ZooKeeperWatcher zkw, Abortable abortable)
+  public ReplicationZKNodeCleaner(Configuration conf, ZKWatcher zkw, Abortable abortable)
       throws IOException {
     try {
       this.zkw = zkw;
@@ -130,7 +130,7 @@ public class ReplicationZKNodeCleaner {
 
   private class ReplicationQueueDeletor extends ReplicationStateZKBase {
 
-    public ReplicationQueueDeletor(ZooKeeperWatcher zk, Configuration conf, Abortable abortable) {
+    public ReplicationQueueDeletor(ZKWatcher zk, Configuration conf, Abortable abortable) {
       super(zk, conf, abortable);
     }
 

hbase-server/src/main/java/org/apache/hadoop/hbase/master/replication/ReplicationManager.java

@@ -30,6 +30,7 @@ import org.apache.hadoop.hbase.Abortable;
 import org.apache.hadoop.hbase.DoNotRetryIOException;
 import org.apache.hadoop.hbase.ReplicationPeerNotFoundException;
 import org.apache.hadoop.hbase.TableName;
+import org.apache.hadoop.hbase.zookeeper.ZKWatcher;
 import org.apache.yetus.audience.InterfaceAudience;
 import org.apache.hadoop.hbase.replication.BaseReplicationEndpoint;
 import org.apache.hadoop.hbase.replication.ReplicationException;
@@ -39,7 +40,6 @@ import org.apache.hadoop.hbase.replication.ReplicationPeerDescription;
 import org.apache.hadoop.hbase.replication.ReplicationPeers;
 import org.apache.hadoop.hbase.replication.ReplicationQueuesClient;
 import org.apache.hadoop.hbase.replication.ReplicationQueuesClientArguments;
-import org.apache.hadoop.hbase.zookeeper.ZooKeeperWatcher;
 
 /**
  * Manages and performs all replication admin operations.
@@ -49,11 +49,11 @@ import org.apache.hadoop.hbase.zookeeper.ZooKeeperWatcher;
 public class ReplicationManager {
 
   private final Configuration conf;
-  private final ZooKeeperWatcher zkw;
+  private final ZKWatcher zkw;
   private final ReplicationQueuesClient replicationQueuesClient;
   private final ReplicationPeers replicationPeers;
 
-  public ReplicationManager(Configuration conf, ZooKeeperWatcher zkw, Abortable abortable)
+  public ReplicationManager(Configuration conf, ZKWatcher zkw, Abortable abortable)
       throws IOException {
     this.conf = conf;
     this.zkw = zkw;

hbase-server/src/main/java/org/apache/hadoop/hbase/procedure/ZKProcedureCoordinator.java

@@ -24,12 +24,12 @@ import java.util.List;
 
 import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
+import org.apache.hadoop.hbase.zookeeper.ZKWatcher;
 import org.apache.yetus.audience.InterfaceAudience;
 import org.apache.hadoop.hbase.errorhandling.ForeignException;
 import org.apache.hadoop.hbase.shaded.protobuf.ProtobufUtil;
 import org.apache.hadoop.hbase.zookeeper.ZKUtil;
 import org.apache.hadoop.hbase.zookeeper.ZNodePaths;
-import org.apache.hadoop.hbase.zookeeper.ZooKeeperWatcher;
 import org.apache.zookeeper.KeeperException;
 
 /**
@@ -41,7 +41,7 @@ public class ZKProcedureCoordinator implements ProcedureCoordinatorRpcs {
   private ZKProcedureUtil zkProc = null;
   protected ProcedureCoordinator coordinator = null;  // if started this should be non-null
 
-  ZooKeeperWatcher watcher;
+  ZKWatcher watcher;
   String procedureType;
   String coordName;
 
@@ -52,7 +52,7 @@ public class ZKProcedureCoordinator implements ProcedureCoordinatorRpcs {
    * @param coordName name of the node running the coordinator
    * @throws KeeperException if an unexpected zk error occurs
    */
-  public ZKProcedureCoordinator(ZooKeeperWatcher watcher,
+  public ZKProcedureCoordinator(ZKWatcher watcher,
       String procedureClass, String coordName) {
     this.watcher = watcher;
     this.procedureType = procedureClass;

hbase-server/src/main/java/org/apache/hadoop/hbase/procedure/ZKProcedureMemberRpcs.java

@@ -23,13 +23,13 @@ import java.util.List;
 
 import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
+import org.apache.hadoop.hbase.zookeeper.ZKWatcher;
 import org.apache.yetus.audience.InterfaceAudience;
 import org.apache.hadoop.hbase.errorhandling.ForeignException;
 import org.apache.hadoop.hbase.shaded.protobuf.ProtobufUtil;
 import org.apache.hadoop.hbase.util.Bytes;
 import org.apache.hadoop.hbase.zookeeper.ZKUtil;
 import org.apache.hadoop.hbase.zookeeper.ZNodePaths;
-import org.apache.hadoop.hbase.zookeeper.ZooKeeperWatcher;
 import org.apache.zookeeper.KeeperException;
 
 /**
@@ -61,12 +61,12 @@ public class ZKProcedureMemberRpcs implements ProcedureMemberRpcs {
 
   /**
    * Must call {@link #start(String, ProcedureMember)} before this can be used.
-   * @param watcher {@link ZooKeeperWatcher} to be owned by <tt>this</tt>. Closed via
+   * @param watcher {@link ZKWatcher} to be owned by <tt>this</tt>. Closed via
    *          {@link #close()}.
    * @param procType name of the znode describing the procedure type
    * @throws KeeperException if we can't reach zookeeper
    */
-  public ZKProcedureMemberRpcs(final ZooKeeperWatcher watcher, final String procType)
+  public ZKProcedureMemberRpcs(final ZKWatcher watcher, final String procType)
       throws KeeperException {
     this.zkController = new ZKProcedureUtil(watcher, procType) {
       @Override

hbase-server/src/main/java/org/apache/hadoop/hbase/procedure/ZKProcedureUtil.java

@@ -23,11 +23,11 @@ import java.util.List;
 
 import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
+import org.apache.hadoop.hbase.zookeeper.ZKListener;
+import org.apache.hadoop.hbase.zookeeper.ZKWatcher;
 import org.apache.yetus.audience.InterfaceAudience;
 import org.apache.hadoop.hbase.zookeeper.ZKUtil;
 import org.apache.hadoop.hbase.zookeeper.ZNodePaths;
-import org.apache.hadoop.hbase.zookeeper.ZooKeeperListener;
-import org.apache.hadoop.hbase.zookeeper.ZooKeeperWatcher;
 import org.apache.zookeeper.KeeperException;
 
 /**
@@ -50,7 +50,7 @@ import org.apache.zookeeper.KeeperException;
  */
 @InterfaceAudience.Private
 public abstract class ZKProcedureUtil
-    extends ZooKeeperListener implements Closeable {
+    extends ZKListener implements Closeable {
 
   private static final Log LOG = LogFactory.getLog(ZKProcedureUtil.class);
 
@@ -73,7 +73,7 @@ public abstract class ZKProcedureUtil
    * @param procDescription name of the znode describing the procedure to run
    * @throws KeeperException when the procedure znodes cannot be created
    */
-  public ZKProcedureUtil(ZooKeeperWatcher watcher, String procDescription)
+  public ZKProcedureUtil(ZKWatcher watcher, String procDescription)
       throws KeeperException {
     super(watcher);
     // make sure we are listening for events
@@ -157,7 +157,7 @@ public abstract class ZKProcedureUtil
     return ZNodePaths.joinZNode(controller.abortZnode, opInstanceName);
   }
 
-  public ZooKeeperWatcher getWatcher() {
+  public ZKWatcher getWatcher() {
     return watcher;
   }
 

hbase-server/src/main/java/org/apache/hadoop/hbase/procedure/flush/RegionServerFlushTableProcedureManager.java

@@ -48,9 +48,8 @@ import org.apache.hadoop.hbase.procedure.SubprocedureFactory;
 import org.apache.hadoop.hbase.procedure.ZKProcedureMemberRpcs;
 import org.apache.hadoop.hbase.regionserver.HRegion;
 import org.apache.hadoop.hbase.regionserver.HRegionServer;
-import org.apache.hadoop.hbase.regionserver.Region;
 import org.apache.hadoop.hbase.regionserver.RegionServerServices;
-import org.apache.hadoop.hbase.zookeeper.ZooKeeperWatcher;
+import org.apache.hadoop.hbase.zookeeper.ZKWatcher;
 import org.apache.zookeeper.KeeperException;
 
 /**
@@ -320,7 +319,7 @@ public class RegionServerFlushTableProcedureManager extends RegionServerProcedur
   @Override
   public void initialize(RegionServerServices rss) throws KeeperException {
     this.rss = rss;
-    ZooKeeperWatcher zkw = rss.getZooKeeper();
+    ZKWatcher zkw = rss.getZooKeeper();
     this.memberRpcs = new ZKProcedureMemberRpcs(zkw,
       MasterFlushTableProcedureManager.FLUSH_TABLE_PROCEDURE_SIGNATURE);
 

hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/HRegionServer.java

@@ -162,10 +162,10 @@ import org.apache.hadoop.hbase.zookeeper.ClusterStatusTracker;
 import org.apache.hadoop.hbase.zookeeper.MasterAddressTracker;
 import org.apache.hadoop.hbase.zookeeper.MetaTableLocator;
 import org.apache.hadoop.hbase.zookeeper.ZKClusterId;
+import org.apache.hadoop.hbase.zookeeper.ZKNodeTracker;
 import org.apache.hadoop.hbase.zookeeper.ZKUtil;
+import org.apache.hadoop.hbase.zookeeper.ZKWatcher;
 import org.apache.hadoop.hbase.zookeeper.ZNodePaths;
-import org.apache.hadoop.hbase.zookeeper.ZooKeeperNodeTracker;
-import org.apache.hadoop.hbase.zookeeper.ZooKeeperWatcher;
 import org.apache.hadoop.ipc.RemoteException;
 import org.apache.hadoop.metrics2.util.MBeans;
 import org.apache.hadoop.util.ReflectionUtils;
@@ -380,7 +380,7 @@ public class HRegionServer extends HasThread implements
   final AtomicBoolean online = new AtomicBoolean(false);
 
   // zookeeper connection and watcher
-  protected ZooKeeperWatcher zooKeeper;
+  protected ZKWatcher zooKeeper;
 
   // master address tracker
   private MasterAddressTracker masterAddressTracker;
@@ -616,7 +616,7 @@ public class HRegionServer extends HasThread implements
       // Some unit tests don't need a cluster, so no zookeeper at all
       if (!conf.getBoolean("hbase.testing.nocluster", false)) {
         // Open connection to zookeeper and set primary watcher
-        zooKeeper = new ZooKeeperWatcher(conf, getProcessName() + ":" +
+        zooKeeper = new ZKWatcher(conf, getProcessName() + ":" +
           rpcServices.isa.getPort(), this, canCreateBaseZNode());
 
         // If no master in cluster, skip trying to track one or look for a cluster status.
@@ -905,7 +905,7 @@ public class HRegionServer extends HasThread implements
    * @throws IOException any IO exception, plus if the RS is stopped
    * @throws InterruptedException
    */
-  private void blockAndCheckIfStopped(ZooKeeperNodeTracker tracker)
+  private void blockAndCheckIfStopped(ZKNodeTracker tracker)
       throws IOException, InterruptedException {
     while (tracker.blockUntilAvailable(this.msgInterval, false) == null) {
       if (this.stopped) {
@@ -2886,7 +2886,7 @@ public class HRegionServer extends HasThread implements
   }
 
   @Override
-  public ZooKeeperWatcher getZooKeeper() {
+  public ZKWatcher getZooKeeper() {
     return zooKeeper;
   }
 

hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/MetricsRegionServerWrapperImpl.java

@@ -42,7 +42,7 @@ import org.apache.hadoop.hbase.regionserver.wal.MetricsWALSource;
 import org.apache.hadoop.hbase.util.EnvironmentEdgeManager;
 import org.apache.hadoop.hbase.util.FSUtils;
 import org.apache.hadoop.hbase.wal.WALProvider;
-import org.apache.hadoop.hbase.zookeeper.ZooKeeperWatcher;
+import org.apache.hadoop.hbase.zookeeper.ZKWatcher;
 import org.apache.hadoop.hdfs.DFSHedgedReadMetrics;
 import org.apache.hadoop.metrics2.MetricsExecutor;
 import org.apache.yetus.audience.InterfaceAudience;
@@ -187,7 +187,7 @@ class MetricsRegionServerWrapperImpl
 
   @Override
   public String getZookeeperQuorum() {
-    ZooKeeperWatcher zk = regionServer.getZooKeeper();
+    ZKWatcher zk = regionServer.getZooKeeper();
     if (zk == null) {
       return "";
     }

hbase-server/src/main/java/org/apache/hadoop/hbase/regionserver/snapshot/RegionServerSnapshotManager.java

@@ -38,6 +38,7 @@ import org.apache.hadoop.hbase.DaemonThreadFactory;
 import org.apache.hadoop.hbase.DroppedSnapshotException;
 import org.apache.hadoop.hbase.HBaseInterfaceAudience;
 import org.apache.hadoop.hbase.TableName;
+import org.apache.hadoop.hbase.zookeeper.ZKWatcher;
 import org.apache.yetus.audience.InterfaceAudience;
 import org.apache.yetus.audience.InterfaceStability;
 import org.apache.hadoop.hbase.client.RegionReplicaUtil;
@@ -53,11 +54,9 @@ import org.apache.hadoop.hbase.procedure.SubprocedureFactory;
 import org.apache.hadoop.hbase.procedure.ZKProcedureMemberRpcs;
 import org.apache.hadoop.hbase.regionserver.HRegion;
 import org.apache.hadoop.hbase.regionserver.HRegionServer;
-import org.apache.hadoop.hbase.regionserver.Region;
 import org.apache.hadoop.hbase.regionserver.RegionServerServices;
 import org.apache.hadoop.hbase.shaded.protobuf.generated.SnapshotProtos.SnapshotDescription;
 import org.apache.hadoop.hbase.snapshot.SnapshotCreationException;
-import org.apache.hadoop.hbase.zookeeper.ZooKeeperWatcher;
 import org.apache.zookeeper.KeeperException;
 
 /**
@@ -394,7 +393,7 @@ public class RegionServerSnapshotManager extends RegionServerProcedureManager {
   @Override
   public void initialize(RegionServerServices rss) throws KeeperException {
     this.rss = rss;
-    ZooKeeperWatcher zkw = rss.getZooKeeper();
+    ZKWatcher zkw = rss.getZooKeeper();
     this.memberRpcs = new ZKProcedureMemberRpcs(zkw,
         SnapshotManager.ONLINE_SNAPSHOT_CONTROLLER_DESCRIPTION);
 

hbase-server/src/main/java/org/apache/hadoop/hbase/replication/HBaseReplicationEndpoint.java

@@ -26,13 +26,13 @@ import java.util.UUID;
 
 import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
+import org.apache.hadoop.hbase.zookeeper.ZKListener;
 import org.apache.yetus.audience.InterfaceAudience;
 import org.apache.hadoop.hbase.Abortable;
 import org.apache.hadoop.hbase.ServerName;
 import org.apache.hadoop.hbase.zookeeper.ZKClusterId;
 import org.apache.hadoop.hbase.zookeeper.ZKUtil;
-import org.apache.hadoop.hbase.zookeeper.ZooKeeperListener;
+import org.apache.hadoop.hbase.zookeeper.ZKWatcher;
-import org.apache.hadoop.hbase.zookeeper.ZooKeeperWatcher;
 import org.apache.zookeeper.KeeperException;
 import org.apache.zookeeper.KeeperException.AuthFailedException;
 import org.apache.zookeeper.KeeperException.ConnectionLossException;
@@ -50,7 +50,7 @@ public abstract class HBaseReplicationEndpoint extends BaseReplicationEndpoint
 
   private static final Log LOG = LogFactory.getLog(HBaseReplicationEndpoint.class);
 
-  private ZooKeeperWatcher zkw = null; // FindBugs: MT_CORRECTNESS
+  private ZKWatcher zkw = null; // FindBugs: MT_CORRECTNESS
 
   private List<ServerName> regionServers = new ArrayList<>(0);
   private long lastRegionServerUpdate;
@@ -123,7 +123,7 @@ public abstract class HBaseReplicationEndpoint extends BaseReplicationEndpoint
    * Get the ZK connection to this peer
    * @return zk connection
    */
-  protected ZooKeeperWatcher getZkw() {
+  protected ZKWatcher getZkw() {
     return zkw;
   }
 
@@ -133,7 +133,7 @@ public abstract class HBaseReplicationEndpoint extends BaseReplicationEndpoint
    */
   void reloadZkWatcher() throws IOException {
     if (zkw != null) zkw.close();
-    zkw = new ZooKeeperWatcher(ctx.getConfiguration(),
+    zkw = new ZKWatcher(ctx.getConfiguration(),
         "connection to cluster: " + ctx.getPeerId(), this);
     getZkw().registerListener(new PeerRegionServerListener(this));
   }
@@ -155,7 +155,7 @@ public abstract class HBaseReplicationEndpoint extends BaseReplicationEndpoint
    * @param zkw zk connection to use
    * @return list of region server addresses or an empty list if the slave is unavailable
    */
-  protected static List<ServerName> fetchSlavesAddresses(ZooKeeperWatcher zkw)
+  protected static List<ServerName> fetchSlavesAddresses(ZKWatcher zkw)
       throws KeeperException {
     List<String> children = ZKUtil.listChildrenAndWatchForNewChildren(zkw, zkw.znodePaths.rsZNode);
     if (children == null) {
@@ -210,7 +210,7 @@ public abstract class HBaseReplicationEndpoint extends BaseReplicationEndpoint
   /**
    * Tracks changes to the list of region servers in a peer's cluster.
    */
-  public static class PeerRegionServerListener extends ZooKeeperListener {
+  public static class PeerRegionServerListener extends ZKListener {
 
     private final HBaseReplicationEndpoint replicationEndpoint;
     private final String regionServerListNode;

hbase-server/src/main/java/org/apache/hadoop/hbase/replication/master/ReplicationHFileCleaner.java

@@ -28,14 +28,13 @@ import org.apache.hadoop.fs.FileStatus;
 import org.apache.hadoop.hbase.Abortable;
 import org.apache.hadoop.hbase.HBaseInterfaceAudience;
 import org.apache.hadoop.hbase.HConstants;
-import org.apache.hadoop.hbase.ZooKeeperConnectionException;
 import org.apache.yetus.audience.InterfaceAudience;
 import org.apache.hadoop.hbase.master.cleaner.BaseHFileCleanerDelegate;
 import org.apache.hadoop.hbase.master.cleaner.HFileCleaner;
 import org.apache.hadoop.hbase.replication.ReplicationFactory;
 import org.apache.hadoop.hbase.replication.ReplicationQueuesClient;
 import org.apache.hadoop.hbase.replication.ReplicationQueuesClientArguments;
-import org.apache.hadoop.hbase.zookeeper.ZooKeeperWatcher;
+import org.apache.hadoop.hbase.zookeeper.ZKWatcher;
 import org.apache.zookeeper.KeeperException;
 
 /**
@@ -45,7 +44,7 @@ import org.apache.zookeeper.KeeperException;
 @InterfaceAudience.LimitedPrivate(HBaseInterfaceAudience.CONFIG)
 public class ReplicationHFileCleaner extends BaseHFileCleanerDelegate {
   private static final Log LOG = LogFactory.getLog(ReplicationHFileCleaner.class);
-  private ZooKeeperWatcher zkw;
+  private ZKWatcher zkw;
   private ReplicationQueuesClient rqc;
   private boolean stopped = false;
 
@@ -130,14 +129,14 @@ public class ReplicationHFileCleaner extends BaseHFileCleanerDelegate {
     // I can close myself when time comes.
     Configuration conf = new Configuration(config);
     try {
-      setConf(conf, new ZooKeeperWatcher(conf, "replicationHFileCleaner", null));
+      setConf(conf, new ZKWatcher(conf, "replicationHFileCleaner", null));
     } catch (IOException e) {
       LOG.error("Error while configuring " + this.getClass().getName(), e);
     }
   }
 
   @VisibleForTesting
-  public void setConf(Configuration conf, ZooKeeperWatcher zk) {
+  public void setConf(Configuration conf, ZKWatcher zk) {
     super.setConf(conf);
     try {
       initReplicationQueuesClient(conf, zk);
@@ -146,7 +145,7 @@ public class ReplicationHFileCleaner extends BaseHFileCleanerDelegate {
     }
   }
 
-  private void initReplicationQueuesClient(Configuration conf, ZooKeeperWatcher zk)
+  private void initReplicationQueuesClient(Configuration conf, ZKWatcher zk)
       throws Exception {
     this.zkw = zk;
     this.rqc = ReplicationFactory.getReplicationQueuesClient(new ReplicationQueuesClientArguments(

hbase-server/src/main/java/org/apache/hadoop/hbase/replication/master/ReplicationLogCleaner.java

@@ -21,6 +21,7 @@ package org.apache.hadoop.hbase.replication.master;
 import org.apache.hadoop.hbase.shaded.com.google.common.annotations.VisibleForTesting;
 import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
+import org.apache.hadoop.hbase.zookeeper.ZKWatcher;
 import org.apache.yetus.audience.InterfaceAudience;
 import org.apache.hadoop.conf.Configuration;
 import org.apache.hadoop.fs.FileStatus;
@@ -30,7 +31,6 @@ import org.apache.hadoop.hbase.master.cleaner.BaseLogCleanerDelegate;
 import org.apache.hadoop.hbase.replication.ReplicationFactory;
 import org.apache.hadoop.hbase.replication.ReplicationQueuesClient;
 import org.apache.hadoop.hbase.replication.ReplicationQueuesClientArguments;
-import org.apache.hadoop.hbase.zookeeper.ZooKeeperWatcher;
 
 import java.io.IOException;
 import java.util.Collections;
@@ -48,7 +48,7 @@ import org.apache.zookeeper.KeeperException;
 @InterfaceAudience.LimitedPrivate(HBaseInterfaceAudience.CONFIG)
 public class ReplicationLogCleaner extends BaseLogCleanerDelegate {
   private static final Log LOG = LogFactory.getLog(ReplicationLogCleaner.class);
-  private ZooKeeperWatcher zkw;
+  private ZKWatcher zkw;
   private ReplicationQueuesClient replicationQueues;
   private boolean stopped = false;
   private Set<String> wals;
@@ -101,14 +101,14 @@ public class ReplicationLogCleaner extends BaseLogCleanerDelegate {
     // I can close myself when comes time.
     Configuration conf = new Configuration(config);
     try {
-      setConf(conf, new ZooKeeperWatcher(conf, "replicationLogCleaner", null));
+      setConf(conf, new ZKWatcher(conf, "replicationLogCleaner", null));
     } catch (IOException e) {
       LOG.error("Error while configuring " + this.getClass().getName(), e);
     }
   }
 
   @VisibleForTesting
-  public void setConf(Configuration conf, ZooKeeperWatcher zk) {
+  public void setConf(Configuration conf, ZKWatcher zk) {
     super.setConf(conf);
     try {
       this.zkw = zk;

hbase-server/src/main/java/org/apache/hadoop/hbase/replication/master/TableCFsUpdater.java

@@ -29,7 +29,7 @@ import org.apache.hadoop.hbase.shaded.protobuf.generated.ReplicationProtos;
 import org.apache.hadoop.hbase.replication.ReplicationPeerConfig;
 import org.apache.hadoop.hbase.replication.ReplicationStateZKBase;
 import org.apache.hadoop.hbase.zookeeper.ZKUtil;
-import org.apache.hadoop.hbase.zookeeper.ZooKeeperWatcher;
+import org.apache.hadoop.hbase.zookeeper.ZKWatcher;
 import org.apache.yetus.audience.InterfaceAudience;
 import org.apache.yetus.audience.InterfaceStability;
 import org.apache.zookeeper.KeeperException;
@@ -47,7 +47,7 @@ public class TableCFsUpdater extends ReplicationStateZKBase {
 
   private static final Log LOG = LogFactory.getLog(TableCFsUpdater.class);
 
-  public TableCFsUpdater(ZooKeeperWatcher zookeeper,
+  public TableCFsUpdater(ZKWatcher zookeeper,
                          Configuration conf, Abortable abortable) {
     super(zookeeper, conf, abortable);
   }
@@ -137,7 +137,7 @@ public class TableCFsUpdater extends ReplicationStateZKBase {
       printUsageAndExit();
     } else if (args[0].equals("update")) {
       Configuration conf = HBaseConfiguration.create();
-      ZooKeeperWatcher zkw = new ZooKeeperWatcher(conf, "TableCFsUpdater", null);
+      ZKWatcher zkw = new ZKWatcher(conf, "TableCFsUpdater", null);
       try {
         TableCFsUpdater tableCFsUpdater = new TableCFsUpdater(zkw, conf, null);
         tableCFsUpdater.update();

hbase-server/src/main/java/org/apache/hadoop/hbase/replication/regionserver/DumpReplicationQueues.java

@@ -55,7 +55,7 @@ import org.apache.hadoop.hbase.replication.ReplicationQueuesClient;
 import org.apache.hadoop.hbase.replication.ReplicationQueuesClientArguments;
 import org.apache.hadoop.hbase.replication.ReplicationTracker;
 import org.apache.hadoop.hbase.zookeeper.ZKUtil;
-import org.apache.hadoop.hbase.zookeeper.ZooKeeperWatcher;
+import org.apache.hadoop.hbase.zookeeper.ZKWatcher;
 import org.apache.hadoop.util.Tool;
 import org.apache.hadoop.util.ToolRunner;
 import org.apache.zookeeper.KeeperException;
@@ -211,7 +211,7 @@ public class DumpReplicationQueues extends Configured implements Tool {
     ClusterConnection connection = (ClusterConnection) ConnectionFactory.createConnection(conf);
     Admin admin = connection.getAdmin();
 
-    ZooKeeperWatcher zkw = new ZooKeeperWatcher(conf, "DumpReplicationQueues" + System.currentTimeMillis(),
+    ZKWatcher zkw = new ZKWatcher(conf, "DumpReplicationQueues" + System.currentTimeMillis(),
         new WarnOnlyAbortable(), true);
 
     try {
@@ -302,8 +302,8 @@ public class DumpReplicationQueues extends Configured implements Tool {
     return sb.toString();
   }
 
-  public String dumpQueues(ClusterConnection connection, ZooKeeperWatcher zkw, Set<String> peerIds,
+  public String dumpQueues(ClusterConnection connection, ZKWatcher zkw, Set<String> peerIds,
-      boolean hdfs) throws Exception {
+                           boolean hdfs) throws Exception {
     ReplicationQueuesClient queuesClient;
     ReplicationPeers replicationPeers;
     ReplicationQueues replicationQueues;

hbase-server/src/main/java/org/apache/hadoop/hbase/replication/regionserver/ReplicationSyncUp.java

@@ -33,7 +33,7 @@ import org.apache.hadoop.hbase.ServerName;
 import org.apache.hadoop.hbase.client.ClusterConnection;
 import org.apache.hadoop.hbase.util.FSUtils;
 import org.apache.hadoop.hbase.zookeeper.MetaTableLocator;
-import org.apache.hadoop.hbase.zookeeper.ZooKeeperWatcher;
+import org.apache.hadoop.hbase.zookeeper.ZKWatcher;
 import org.apache.hadoop.util.Tool;
 import org.apache.hadoop.util.ToolRunner;
 
@@ -77,7 +77,7 @@ public class ReplicationSyncUp extends Configured implements Tool {
     ReplicationSourceManager manager;
     FileSystem fs;
     Path oldLogDir, logDir, walRootDir;
-    ZooKeeperWatcher zkw;
+    ZKWatcher zkw;
 
     Abortable abortable = new Abortable() {
       @Override
@@ -91,7 +91,7 @@ public class ReplicationSyncUp extends Configured implements Tool {
     };
 
     zkw =
-        new ZooKeeperWatcher(conf, "syncupReplication" + System.currentTimeMillis(), abortable,
+        new ZKWatcher(conf, "syncupReplication" + System.currentTimeMillis(), abortable,
             true);
 
     walRootDir = FSUtils.getWALRootDir(conf);
@@ -123,9 +123,9 @@ public class ReplicationSyncUp extends Configured implements Tool {
 
   static class DummyServer implements Server {
     String hostname;
-    ZooKeeperWatcher zkw;
+    ZKWatcher zkw;
 
-    DummyServer(ZooKeeperWatcher zkw) {
+    DummyServer(ZKWatcher zkw) {
       // an unique name in case the first run fails
       hostname = System.currentTimeMillis() + ".SyncUpTool.replication.org";
       this.zkw = zkw;
@@ -141,7 +141,7 @@ public class ReplicationSyncUp extends Configured implements Tool {
     }
 
     @Override
-    public ZooKeeperWatcher getZooKeeper() {
+    public ZKWatcher getZooKeeper() {
       return zkw;
     }
 

hbase-server/src/main/java/org/apache/hadoop/hbase/security/access/AccessController.java

@@ -130,7 +130,7 @@ import org.apache.hadoop.hbase.util.EnvironmentEdgeManager;
 import org.apache.hadoop.hbase.util.Pair;
 import org.apache.hadoop.hbase.util.SimpleMutableByteRange;
 import org.apache.hadoop.hbase.wal.WALEdit;
-import org.apache.hadoop.hbase.zookeeper.ZooKeeperWatcher;
+import org.apache.hadoop.hbase.zookeeper.ZKWatcher;
 import org.apache.yetus.audience.InterfaceAudience;
 
 import org.apache.hadoop.hbase.shaded.com.google.common.collect.ArrayListMultimap;
@@ -953,7 +953,7 @@ public class AccessController implements MasterCoprocessor, RegionCoprocessor,
           + " accordingly.");
     }
 
-    ZooKeeperWatcher zk = null;
+    ZKWatcher zk = null;
     if (env instanceof MasterCoprocessorEnvironment) {
       // if running on HMaster
       MasterCoprocessorEnvironment mEnv = (MasterCoprocessorEnvironment)env;

hbase-server/src/main/java/org/apache/hadoop/hbase/security/access/TableAuthManager.java

@@ -39,13 +39,13 @@ import org.apache.hadoop.conf.Configuration;
 import org.apache.hadoop.hbase.AuthUtil;
 import org.apache.hadoop.hbase.Cell;
 import org.apache.hadoop.hbase.TableName;
+import org.apache.hadoop.hbase.zookeeper.ZKWatcher;
 import org.apache.yetus.audience.InterfaceAudience;
 import org.apache.hadoop.hbase.exceptions.DeserializationException;
 import org.apache.hadoop.hbase.security.Superusers;
 import org.apache.hadoop.hbase.security.User;
 import org.apache.hadoop.hbase.security.UserProvider;
 import org.apache.hadoop.hbase.util.Bytes;
-import org.apache.hadoop.hbase.zookeeper.ZooKeeperWatcher;
 import org.apache.zookeeper.KeeperException;
 
 /**
@@ -112,7 +112,7 @@ public class TableAuthManager implements Closeable {
   private ZKPermissionWatcher zkperms;
   private final AtomicLong mtime = new AtomicLong(0L);
 
-  private TableAuthManager(ZooKeeperWatcher watcher, Configuration conf)
+  private TableAuthManager(ZKWatcher watcher, Configuration conf)
       throws IOException {
     this.conf = conf;
 
@@ -734,14 +734,14 @@ public class TableAuthManager implements Closeable {
     return mtime.get();
   }
 
-  private static Map<ZooKeeperWatcher,TableAuthManager> managerMap = new HashMap<>();
+  private static Map<ZKWatcher,TableAuthManager> managerMap = new HashMap<>();
 
   private static Map<TableAuthManager, Integer> refCount = new HashMap<>();
 
   /** Returns a TableAuthManager from the cache. If not cached, constructs a new one. Returned
    * instance should be released back by calling {@link #release(TableAuthManager)}. */
   public synchronized static TableAuthManager getOrCreate(
-      ZooKeeperWatcher watcher, Configuration conf) throws IOException {
+          ZKWatcher watcher, Configuration conf) throws IOException {
     TableAuthManager instance = managerMap.get(watcher);
     if (instance == null) {
       instance = new TableAuthManager(watcher, conf);

hbase-server/src/main/java/org/apache/hadoop/hbase/security/access/ZKPermissionWatcher.java

@@ -20,15 +20,15 @@ package org.apache.hadoop.hbase.security.access;
 
 import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
-import org.apache.yetus.audience.InterfaceAudience;
 import org.apache.hadoop.conf.Configuration;
 import org.apache.hadoop.hbase.DaemonThreadFactory;
 import org.apache.hadoop.hbase.TableName;
 import org.apache.hadoop.hbase.util.Bytes;
+import org.apache.hadoop.hbase.zookeeper.ZKListener;
 import org.apache.hadoop.hbase.zookeeper.ZKUtil;
+import org.apache.hadoop.hbase.zookeeper.ZKWatcher;
 import org.apache.hadoop.hbase.zookeeper.ZNodePaths;
-import org.apache.hadoop.hbase.zookeeper.ZooKeeperListener;
+import org.apache.yetus.audience.InterfaceAudience;
-import org.apache.hadoop.hbase.zookeeper.ZooKeeperWatcher;
 import org.apache.zookeeper.KeeperException;
 
 import java.io.Closeable;
@@ -41,7 +41,6 @@ import java.util.concurrent.ExecutorService;
 import java.util.concurrent.Executors;
 import java.util.concurrent.Future;
 import java.util.concurrent.RejectedExecutionException;
-import java.util.concurrent.atomic.AtomicReference;
 
 /**
  * Handles synchronization of access control list entries and updates
@@ -53,7 +52,7 @@ import java.util.concurrent.atomic.AtomicReference;
  * trigger updates in the {@link TableAuthManager} permission cache.
  */
 @InterfaceAudience.Private
-public class ZKPermissionWatcher extends ZooKeeperListener implements Closeable {
+public class ZKPermissionWatcher extends ZKListener implements Closeable {
   private static final Log LOG = LogFactory.getLog(ZKPermissionWatcher.class);
   // parent node for permissions lists
   static final String ACL_NODE = "acl";
@@ -63,7 +62,7 @@ public class ZKPermissionWatcher extends ZooKeeperListener implements Closeable
   private final ExecutorService executor;
   private Future<?> childrenChangedFuture;
 
-  public ZKPermissionWatcher(ZooKeeperWatcher watcher,
+  public ZKPermissionWatcher(ZKWatcher watcher,
       TableAuthManager authManager, Configuration conf) {
     super(watcher);
     this.authManager = authManager;

hbase-server/src/main/java/org/apache/hadoop/hbase/security/token/AuthenticationTokenSecretManager.java

@@ -27,6 +27,7 @@ import java.util.concurrent.atomic.AtomicLong;
 
 import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
+import org.apache.hadoop.hbase.zookeeper.ZKWatcher;
 import org.apache.yetus.audience.InterfaceAudience;
 import org.apache.hadoop.conf.Configuration;
 import org.apache.hadoop.hbase.Stoppable;
@@ -35,7 +36,6 @@ import org.apache.hadoop.hbase.util.EnvironmentEdgeManager;
 import org.apache.hadoop.hbase.zookeeper.ZKClusterId;
 import org.apache.hadoop.hbase.zookeeper.ZKLeaderManager;
 import org.apache.hadoop.hbase.zookeeper.ZNodePaths;
-import org.apache.hadoop.hbase.zookeeper.ZooKeeperWatcher;
 import org.apache.hadoop.io.Text;
 import org.apache.hadoop.security.token.SecretManager;
 import org.apache.hadoop.security.token.Token;
@@ -89,8 +89,8 @@ public class AuthenticationTokenSecretManager
    * org.apache.hadoop.hbase.ipc.SecureServer so public access is needed.
    */
   public AuthenticationTokenSecretManager(Configuration conf,
-      ZooKeeperWatcher zk, String serverName,
+                                          ZKWatcher zk, String serverName,
-      long keyUpdateInterval, long tokenMaxLifetime) {
+                                          long keyUpdateInterval, long tokenMaxLifetime) {
     this.zkWatcher = new ZKSecretWatcher(conf, zk, this);
     this.keyUpdateInterval = keyUpdateInterval;
     this.tokenMaxLifetime = tokenMaxLifetime;
@@ -144,9 +144,9 @@ public class AuthenticationTokenSecretManager
     AuthenticationKey masterKey = allKeys.get(identifier.getKeyId());
     if(masterKey == null) {
       if(zkWatcher.getWatcher().isAborted()) {
-        LOG.error("ZooKeeperWatcher is abort");
+        LOG.error("ZKWatcher is abort");
         throw new InvalidToken("Token keys could not be sync from zookeeper"
-            + " because of ZooKeeperWatcher abort");
+            + " because of ZKWatcher abort");
       }
       synchronized (this) {
         if (!leaderElector.isAlive() || leaderElector.isStopped()) {
@@ -254,7 +254,7 @@ public class AuthenticationTokenSecretManager
       }
     }
   }
-  
+
   synchronized boolean isCurrentKeyRolled() {
     return currentKey != null;
   }
@@ -297,7 +297,7 @@ public class AuthenticationTokenSecretManager
     private boolean isMaster = false;
     private ZKLeaderManager zkLeader;
 
-    public LeaderElector(ZooKeeperWatcher watcher, String serverName) {
+    public LeaderElector(ZKWatcher watcher, String serverName) {
       setDaemon(true);
       setName("ZKSecretWatcher-leaderElector");
       zkLeader = new ZKLeaderManager(watcher,

hbase-server/src/main/java/org/apache/hadoop/hbase/security/token/TokenUtil.java

@@ -26,6 +26,7 @@ import com.google.protobuf.ByteString;
 import com.google.protobuf.ServiceException;
 import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
+import org.apache.hadoop.hbase.zookeeper.ZKWatcher;
 import org.apache.yetus.audience.InterfaceAudience;
 import org.apache.hadoop.conf.Configuration;
 import org.apache.hadoop.hbase.HConstants;
@@ -37,7 +38,6 @@ import org.apache.hadoop.hbase.protobuf.generated.AuthenticationProtos;
 import org.apache.hadoop.hbase.security.User;
 import org.apache.hadoop.hbase.shaded.protobuf.ProtobufUtil;
 import org.apache.hadoop.hbase.zookeeper.ZKClusterId;
-import org.apache.hadoop.hbase.zookeeper.ZooKeeperWatcher;
 import org.apache.hadoop.io.Text;
 import org.apache.hadoop.mapred.JobConf;
 import org.apache.hadoop.mapreduce.Job;
@@ -289,7 +289,7 @@ public class TokenUtil {
    */
   private static Token<AuthenticationTokenIdentifier> getAuthToken(Configuration conf, User user)
       throws IOException, InterruptedException {
-    ZooKeeperWatcher zkw = new ZooKeeperWatcher(conf, "TokenUtil-getAuthToken", null);
+    ZKWatcher zkw = new ZKWatcher(conf, "TokenUtil-getAuthToken", null);
     try {
       String clusterId = ZKClusterId.readClusterIdZNode(zkw);
       if (clusterId == null) {

hbase-server/src/main/java/org/apache/hadoop/hbase/security/token/ZKSecretWatcher.java

@@ -25,20 +25,20 @@ import java.util.List;
 
 import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
+import org.apache.hadoop.hbase.zookeeper.ZKListener;
+import org.apache.hadoop.hbase.zookeeper.ZKWatcher;
 import org.apache.yetus.audience.InterfaceAudience;
 import org.apache.hadoop.conf.Configuration;
 import org.apache.hadoop.hbase.util.Writables;
 import org.apache.hadoop.hbase.zookeeper.ZKUtil;
 import org.apache.hadoop.hbase.zookeeper.ZNodePaths;
-import org.apache.hadoop.hbase.zookeeper.ZooKeeperListener;
-import org.apache.hadoop.hbase.zookeeper.ZooKeeperWatcher;
 import org.apache.zookeeper.KeeperException;
 
 /**
  * Synchronizes token encryption keys across cluster nodes.
  */
 @InterfaceAudience.Private
-public class ZKSecretWatcher extends ZooKeeperListener {
+public class ZKSecretWatcher extends ZKListener {
   private static final String DEFAULT_ROOT_NODE = "tokenauth";
   private static final String DEFAULT_KEYS_PARENT = "keys";
   private static final Log LOG = LogFactory.getLog(ZKSecretWatcher.class);
@@ -48,7 +48,7 @@ public class ZKSecretWatcher extends ZooKeeperListener {
   private String keysParentZNode;
 
   public ZKSecretWatcher(Configuration conf,
-      ZooKeeperWatcher watcher,
+      ZKWatcher watcher,
       AuthenticationTokenSecretManager secretManager) {
     super(watcher);
     this.secretManager = secretManager;
@@ -214,7 +214,7 @@ public class ZKSecretWatcher extends ZooKeeperListener {
       watcher.abort("Failed serializing key "+key.getKeyId(), ioe);
     }
   }
-  
+
   /**
    * refresh keys
    */
@@ -228,7 +228,7 @@ public class ZKSecretWatcher extends ZooKeeperListener {
       watcher.abort("Error reading changed keys from zookeeper", ke);
     }
   }
-  
+
   /**
    * get token keys parent node
    * @return token keys parent node

hbase-server/src/main/java/org/apache/hadoop/hbase/security/visibility/DefaultVisibilityLabelServiceImpl.java

@@ -52,6 +52,7 @@ import org.apache.hadoop.hbase.Tag;
 import org.apache.hadoop.hbase.TagType;
 import org.apache.hadoop.hbase.TagUtil;
 import org.apache.hadoop.hbase.coprocessor.HasRegionServerServices;
+import org.apache.hadoop.hbase.zookeeper.ZKWatcher;
 import org.apache.yetus.audience.InterfaceAudience;
 import org.apache.hadoop.hbase.client.Delete;
 import org.apache.hadoop.hbase.client.Mutation;
@@ -67,7 +68,6 @@ import org.apache.hadoop.hbase.security.Superusers;
 import org.apache.hadoop.hbase.security.User;
 import org.apache.hadoop.hbase.util.Bytes;
 import org.apache.hadoop.hbase.util.Pair;
-import org.apache.hadoop.hbase.zookeeper.ZooKeeperWatcher;
 
 @InterfaceAudience.Private
 public class DefaultVisibilityLabelServiceImpl implements VisibilityLabelService {
@@ -120,7 +120,7 @@ public class DefaultVisibilityLabelServiceImpl implements VisibilityLabelService
     // This is a CoreCoprocessor. On creation, we should have gotten an environment that
     // implements HasRegionServerServices so we can get at RSS. FIX!!!! Integrate this CP as
     // native service.
-    ZooKeeperWatcher zk = ((HasRegionServerServices)e).getRegionServerServices().getZooKeeper();
+    ZKWatcher zk = ((HasRegionServerServices)e).getRegionServerServices().getZooKeeper();
     try {
       labelsCache = VisibilityLabelsCache.createAndGet(zk, this.conf);
     } catch (IOException ioe) {

hbase-server/src/main/java/org/apache/hadoop/hbase/security/visibility/VisibilityLabelsCache.java

@@ -37,7 +37,7 @@ import org.apache.hadoop.hbase.protobuf.generated.VisibilityLabelsProtos.MultiUs
 import org.apache.hadoop.hbase.protobuf.generated.VisibilityLabelsProtos.UserAuthorizations;
 import org.apache.hadoop.hbase.protobuf.generated.VisibilityLabelsProtos.VisibilityLabel;
 import org.apache.hadoop.hbase.util.Bytes;
-import org.apache.hadoop.hbase.zookeeper.ZooKeeperWatcher;
+import org.apache.hadoop.hbase.zookeeper.ZKWatcher;
 import org.apache.zookeeper.KeeperException;
 
 /**
@@ -64,7 +64,7 @@ public class VisibilityLabelsCache implements VisibilityLabelOrdinalProvider {
    */
   private ReentrantReadWriteLock lock = new ReentrantReadWriteLock();
 
-  private VisibilityLabelsCache(ZooKeeperWatcher watcher, Configuration conf) throws IOException {
+  private VisibilityLabelsCache(ZKWatcher watcher, Configuration conf) throws IOException {
     zkVisibilityWatcher = new ZKVisibilityLabelWatcher(watcher, this, conf);
     try {
       zkVisibilityWatcher.start();
@@ -81,7 +81,7 @@ public class VisibilityLabelsCache implements VisibilityLabelOrdinalProvider {
    * @return Singleton instance of VisibilityLabelsCache
    * @throws IOException
    */
-  public synchronized static VisibilityLabelsCache createAndGet(ZooKeeperWatcher watcher,
+  public synchronized static VisibilityLabelsCache createAndGet(ZKWatcher watcher,
       Configuration conf) throws IOException {
     // VisibilityLabelService#init() for different regions (in same RS) passes same instance of
     // watcher as all get the instance from RS.
@@ -99,7 +99,7 @@ public class VisibilityLabelsCache implements VisibilityLabelOrdinalProvider {
    * @return Singleton instance of VisibilityLabelsCache
    * @throws IllegalStateException
    *           when this is called before calling
-   *           {@link #createAndGet(ZooKeeperWatcher, Configuration)}
+   *           {@link #createAndGet(ZKWatcher, Configuration)}
    */
   public static VisibilityLabelsCache get() {
     // By the time this method is called, the singleton instance of VisibilityLabelsCache should

hbase-server/src/main/java/org/apache/hadoop/hbase/security/visibility/ZKVisibilityLabelWatcher.java

@@ -21,12 +21,12 @@ import java.io.IOException;
 
 import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
+import org.apache.hadoop.hbase.zookeeper.ZKListener;
+import org.apache.hadoop.hbase.zookeeper.ZKWatcher;
 import org.apache.yetus.audience.InterfaceAudience;
 import org.apache.hadoop.conf.Configuration;
 import org.apache.hadoop.hbase.zookeeper.ZKUtil;
 import org.apache.hadoop.hbase.zookeeper.ZNodePaths;
-import org.apache.hadoop.hbase.zookeeper.ZooKeeperListener;
-import org.apache.hadoop.hbase.zookeeper.ZooKeeperWatcher;
 import org.apache.zookeeper.KeeperException;
 
 /**
@@ -34,12 +34,12 @@ import org.apache.zookeeper.KeeperException;
  * /hbase/visibility_labels and will have a serialized form of a set of labels in the system.
  */
 @InterfaceAudience.Private
-public class ZKVisibilityLabelWatcher extends ZooKeeperListener {
+public class ZKVisibilityLabelWatcher extends ZKListener {
 
   private static final Log LOG = LogFactory.getLog(ZKVisibilityLabelWatcher.class);
   private static final String VISIBILITY_LABEL_ZK_PATH = "zookeeper.znode.visibility.label.parent";
   private static final String DEFAULT_VISIBILITY_LABEL_NODE = "visibility/labels";
-  private static final String VISIBILITY_USER_AUTHS_ZK_PATH = 
+  private static final String VISIBILITY_USER_AUTHS_ZK_PATH =
       "zookeeper.znode.visibility.user.auths.parent";
   private static final String DEFAULT_VISIBILITY_USER_AUTHS_NODE = "visibility/user_auths";
 
@@ -47,8 +47,8 @@ public class ZKVisibilityLabelWatcher extends ZooKeeperListener {
   private String labelZnode;
   private String userAuthsZnode;
 
-  public ZKVisibilityLabelWatcher(ZooKeeperWatcher watcher, VisibilityLabelsCache labelsCache,
+  public ZKVisibilityLabelWatcher(ZKWatcher watcher, VisibilityLabelsCache labelsCache,
-      Configuration conf) {
+                                  Configuration conf) {
     super(watcher);
     this.labelsCache = labelsCache;
     String labelZnodeParent = conf.get(VISIBILITY_LABEL_ZK_PATH, DEFAULT_VISIBILITY_LABEL_NODE);
@@ -132,7 +132,7 @@ public class ZKVisibilityLabelWatcher extends ZooKeeperListener {
 
   /**
    * Write a labels mirror or user auths mirror into zookeeper
-   * 
+   *
    * @param data
    * @param labelsOrUserAuths true for writing labels and false for user auths.
    */

hbase-server/src/main/java/org/apache/hadoop/hbase/util/HBaseFsck.java

@@ -130,8 +130,8 @@ import org.apache.hadoop.hbase.wal.WALFactory;
 import org.apache.hadoop.hbase.wal.WALSplitter;
 import org.apache.hadoop.hbase.zookeeper.MetaTableLocator;
 import org.apache.hadoop.hbase.zookeeper.ZKUtil;
+import org.apache.hadoop.hbase.zookeeper.ZKWatcher;
 import org.apache.hadoop.hbase.zookeeper.ZNodePaths;
-import org.apache.hadoop.hbase.zookeeper.ZooKeeperWatcher;
 import org.apache.hadoop.hdfs.protocol.AlreadyBeingCreatedException;
 import org.apache.hadoop.ipc.RemoteException;
 import org.apache.hadoop.security.UserGroupInformation;
@@ -316,7 +316,7 @@ public class HBaseFsck extends Configured implements Closeable {
 
   private Map<TableName, Set<String>> skippedRegions = new HashMap<>();
 
-  private ZooKeeperWatcher zkw = null;
+  private ZKWatcher zkw = null;
   private String hbckEphemeralNodePath = null;
   private boolean hbckZodeCreated = false;
 
@@ -1918,8 +1918,8 @@ public class HBaseFsck extends Configured implements Closeable {
     return true;
   }
 
-  private ZooKeeperWatcher createZooKeeperWatcher() throws IOException {
+  private ZKWatcher createZooKeeperWatcher() throws IOException {
-    return new ZooKeeperWatcher(getConf(), "hbase Fsck", new Abortable() {
+    return new ZKWatcher(getConf(), "hbase Fsck", new Abortable() {
       @Override
       public void abort(String why, Throwable e) {
         LOG.error(why, e);

hbase-server/src/main/java/org/apache/hadoop/hbase/util/RegionMover.java

@@ -62,7 +62,7 @@ import org.apache.hadoop.hbase.client.Scan;
 import org.apache.hadoop.hbase.client.Table;
 import org.apache.hadoop.hbase.filter.FirstKeyOnlyFilter;
 import org.apache.hadoop.hbase.zookeeper.MetaTableLocator;
-import org.apache.hadoop.hbase.zookeeper.ZooKeeperWatcher;
+import org.apache.hadoop.hbase.zookeeper.ZKWatcher;
 import org.apache.yetus.audience.InterfaceAudience;
 
 /**
@@ -900,7 +900,7 @@ public class RegionMover extends AbstractHBaseTool {
       return null;
     }
     if (region.isMetaRegion()) {
-      ZooKeeperWatcher zkw = new ZooKeeperWatcher(admin.getConfiguration(), "region_mover", null);
+      ZKWatcher zkw = new ZKWatcher(admin.getConfiguration(), "region_mover", null);
       MetaTableLocator locator = new MetaTableLocator();
       int maxWaitInSeconds =
           admin.getConfiguration().getInt(MOVE_WAIT_MAX_KEY, DEFAULT_MOVE_WAIT_MAX);

hbase-server/src/main/java/org/apache/hadoop/hbase/util/ZKDataMigrator.java

@@ -25,14 +25,14 @@ import java.util.Map;
 import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
 import org.apache.hadoop.hbase.TableName;
-import org.apache.yetus.audience.InterfaceAudience;
 import org.apache.hadoop.hbase.client.TableState;
 import org.apache.hadoop.hbase.exceptions.DeserializationException;
 import org.apache.hadoop.hbase.shaded.protobuf.ProtobufUtil;
 import org.apache.hadoop.hbase.shaded.protobuf.generated.ZooKeeperProtos;
 import org.apache.hadoop.hbase.zookeeper.ZKUtil;
+import org.apache.hadoop.hbase.zookeeper.ZKWatcher;
 import org.apache.hadoop.hbase.zookeeper.ZNodePaths;
-import org.apache.hadoop.hbase.zookeeper.ZooKeeperWatcher;
+import org.apache.yetus.audience.InterfaceAudience;
 import org.apache.zookeeper.KeeperException;
 
 /**
@@ -52,7 +52,7 @@ public class ZKDataMigrator {
    * table descriptor based states.
    */
   @Deprecated
-  public static Map<TableName, TableState.State> queryForTableStates(ZooKeeperWatcher zkw)
+  public static Map<TableName, TableState.State> queryForTableStates(ZKWatcher zkw)
       throws KeeperException, InterruptedException {
     Map<TableName, TableState.State> rv = new HashMap<>();
     List<String> children = ZKUtil.listChildrenNoWatch(zkw, zkw.znodePaths.tableZNode);
@@ -86,14 +86,14 @@ public class ZKDataMigrator {
 
   /**
    * Gets table state from ZK.
-   * @param zkw ZooKeeperWatcher instance to use
+   * @param zkw ZKWatcher instance to use
    * @param tableName table we're checking
    * @return Null or {@link ZooKeeperProtos.DeprecatedTableState.State} found in znode.
    * @throws KeeperException
    */
   @Deprecated
   private static  ZooKeeperProtos.DeprecatedTableState.State getTableState(
-      final ZooKeeperWatcher zkw, final TableName tableName)
+          final ZKWatcher zkw, final TableName tableName)
       throws KeeperException, InterruptedException {
     String znode = ZNodePaths.joinZNode(zkw.znodePaths.tableZNode, tableName.getNameAsString());
     byte [] data = ZKUtil.getData(zkw, znode);

hbase-server/src/main/java/org/apache/hadoop/hbase/util/hbck/ReplicationChecker.java

@@ -27,13 +27,13 @@ import java.util.Map.Entry;
 import java.util.Set;
 
 import org.apache.hadoop.conf.Configuration;
+import org.apache.hadoop.hbase.zookeeper.ZKWatcher;
 import org.apache.yetus.audience.InterfaceAudience;
 import org.apache.hadoop.hbase.client.ClusterConnection;
 import org.apache.hadoop.hbase.master.cleaner.ReplicationZKNodeCleaner;
 import org.apache.hadoop.hbase.replication.ReplicationQueueInfo;
 import org.apache.hadoop.hbase.util.HBaseFsck;
 import org.apache.hadoop.hbase.util.HBaseFsck.ErrorReporter;
-import org.apache.hadoop.hbase.zookeeper.ZooKeeperWatcher;
 
 /*
  * Check and fix undeleted replication queues for removed peerId.
@@ -47,8 +47,8 @@ public class ReplicationChecker {
   private Set<String> undeletedHFileRefsQueueIds = new HashSet<>();
   private final ReplicationZKNodeCleaner cleaner;
 
-  public ReplicationChecker(Configuration conf, ZooKeeperWatcher zkw, ClusterConnection connection,
+  public ReplicationChecker(Configuration conf, ZKWatcher zkw, ClusterConnection connection,
-      ErrorReporter errorReporter) throws IOException {
+                            ErrorReporter errorReporter) throws IOException {
     this.cleaner = new ReplicationZKNodeCleaner(conf, zkw, connection);
     this.errorReporter = errorReporter;
   }

hbase-server/src/main/resources/hbase-webapps/master/zk.jsp

@@ -20,11 +20,11 @@
 <%@ page contentType="text/html;charset=UTF-8"
   import="org.apache.commons.lang3.StringEscapeUtils"
   import="org.apache.hadoop.hbase.zookeeper.ZKUtil"
-  import="org.apache.hadoop.hbase.zookeeper.ZooKeeperWatcher"
+  import="org.apache.hadoop.hbase.zookeeper.ZKWatcher"
   import="org.apache.hadoop.hbase.HBaseConfiguration"
   import="org.apache.hadoop.hbase.master.HMaster"%><%
   HMaster master = (HMaster)getServletContext().getAttribute(HMaster.MASTER);
-  ZooKeeperWatcher watcher = master.getZooKeeper();
+  ZKWatcher watcher = master.getZooKeeper();
 %>
 <!DOCTYPE html>
 <?xml version="1.0" encoding="UTF-8" ?>

hbase-server/src/test/java/org/apache/hadoop/hbase/HBaseTestingUtility.java

@@ -68,6 +68,7 @@ import org.apache.hadoop.hbase.client.ImmutableHRegionInfo;
 import org.apache.hadoop.hbase.client.RegionInfo;
 import org.apache.hadoop.hbase.client.RegionInfoBuilder;
 import org.apache.hadoop.hbase.trace.TraceUtil;
+import org.apache.hadoop.hbase.zookeeper.ZKWatcher;
 import org.apache.yetus.audience.InterfaceAudience;
 import org.apache.hadoop.hbase.client.Admin;
 import org.apache.hadoop.hbase.client.BufferedMutator;
@@ -133,7 +134,6 @@ import org.apache.hadoop.hbase.wal.WALFactory;
 import org.apache.hadoop.hbase.zookeeper.EmptyWatcher;
 import org.apache.hadoop.hbase.zookeeper.MiniZooKeeperCluster;
 import org.apache.hadoop.hbase.zookeeper.ZKConfig;
-import org.apache.hadoop.hbase.zookeeper.ZooKeeperWatcher;
 import org.apache.hadoop.hdfs.DFSClient;
 import org.apache.hadoop.hdfs.DistributedFileSystem;
 import org.apache.hadoop.hdfs.MiniDFSCluster;
@@ -2752,7 +2752,7 @@ public class HBaseTestingUtility extends HBaseCommonTestingUtility {
     }
   }
 
-  public void expireSession(ZooKeeperWatcher nodeZK) throws Exception {
+  public void expireSession(ZKWatcher nodeZK) throws Exception {
    expireSession(nodeZK, false);
   }
 
@@ -2767,7 +2767,7 @@ public class HBaseTestingUtility extends HBaseCommonTestingUtility {
    * @param checkStatus - true to check if we can create a Table with the
    *                    current configuration.
    */
-  public void expireSession(ZooKeeperWatcher nodeZK, boolean checkStatus)
+  public void expireSession(ZKWatcher nodeZK, boolean checkStatus)
     throws Exception {
     Configuration c = new Configuration(this.conf);
     String quorumServers = ZKConfig.getZKQuorumServersString(c);
@@ -2882,18 +2882,18 @@ public class HBaseTestingUtility extends HBaseCommonTestingUtility {
   private HBaseAdmin hbaseAdmin = null;
 
   /**
-   * Returns a ZooKeeperWatcher instance.
+   * Returns a ZKWatcher instance.
    * This instance is shared between HBaseTestingUtility instance users.
    * Don't close it, it will be closed automatically when the
    * cluster shutdowns
    *
-   * @return The ZooKeeperWatcher instance.
+   * @return The ZKWatcher instance.
    * @throws IOException
    */
-  public synchronized ZooKeeperWatcher getZooKeeperWatcher()
+  public synchronized ZKWatcher getZooKeeperWatcher()
     throws IOException {
     if (zooKeeperWatcher == null) {
-      zooKeeperWatcher = new ZooKeeperWatcher(conf, "testing utility",
+      zooKeeperWatcher = new ZKWatcher(conf, "testing utility",
         new Abortable() {
         @Override public void abort(String why, Throwable e) {
           throw new RuntimeException("Unexpected abort in HBaseTestingUtility:"+why, e);
@@ -2903,7 +2903,7 @@ public class HBaseTestingUtility extends HBaseCommonTestingUtility {
     }
     return zooKeeperWatcher;
   }
-  private ZooKeeperWatcher zooKeeperWatcher;
+  private ZKWatcher zooKeeperWatcher;
 
 
 
@@ -3508,13 +3508,13 @@ public class HBaseTestingUtility extends HBaseCommonTestingUtility {
   }
 
   /**
-   * Gets a ZooKeeperWatcher.
+   * Gets a ZKWatcher.
    * @param TEST_UTIL
    */
-  public static ZooKeeperWatcher getZooKeeperWatcher(
+  public static ZKWatcher getZooKeeperWatcher(
       HBaseTestingUtility TEST_UTIL) throws ZooKeeperConnectionException,
       IOException {
-    ZooKeeperWatcher zkw = new ZooKeeperWatcher(TEST_UTIL.getConfiguration(),
+    ZKWatcher zkw = new ZKWatcher(TEST_UTIL.getConfiguration(),
         "unittest", new Abortable() {
           boolean aborted = false;
 

hbase-server/src/test/java/org/apache/hadoop/hbase/MockRegionServerServices.java

@@ -23,7 +23,6 @@ import java.util.Collections;
 import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
-import java.util.Set;
 import java.util.concurrent.ConcurrentSkipListMap;
 import java.util.concurrent.atomic.AtomicBoolean;
 
@@ -54,7 +53,7 @@ import org.apache.hadoop.hbase.regionserver.throttle.ThroughputController;
 import org.apache.hadoop.hbase.util.Bytes;
 import org.apache.hadoop.hbase.wal.WAL;
 import org.apache.hadoop.hbase.zookeeper.MetaTableLocator;
-import org.apache.hadoop.hbase.zookeeper.ZooKeeperWatcher;
+import org.apache.hadoop.hbase.zookeeper.ZKWatcher;
 import org.apache.zookeeper.KeeperException;
 
 import org.apache.hadoop.hbase.shaded.protobuf.generated.HBaseProtos;
@@ -71,18 +70,18 @@ public class MockRegionServerServices implements RegionServerServices {
     new ConcurrentSkipListMap<>(Bytes.BYTES_COMPARATOR);
   private HFileSystem hfs = null;
   private final Configuration conf;
-  private ZooKeeperWatcher zkw = null;
+  private ZKWatcher zkw = null;
   private ServerName serverName = null;
   private RpcServerInterface rpcServer = null;
   private volatile boolean abortRequested;
   private volatile boolean stopping = false;
   private final AtomicBoolean running = new AtomicBoolean(true);
 
-  MockRegionServerServices(ZooKeeperWatcher zkw) {
+  MockRegionServerServices(ZKWatcher zkw) {
     this(zkw, null);
   }
 
-  MockRegionServerServices(ZooKeeperWatcher zkw, ServerName serverName) {
+  MockRegionServerServices(ZKWatcher zkw, ServerName serverName) {
     this.zkw = zkw;
     this.serverName = serverName;
     this.conf = (zkw == null ? new Configuration() : zkw.getConfiguration());
@@ -167,7 +166,7 @@ public class MockRegionServerServices implements RegionServerServices {
   }
 
   @Override
-  public ZooKeeperWatcher getZooKeeper() {
+  public ZKWatcher getZooKeeper() {
     return zkw;
   }
 

hbase-server/src/test/java/org/apache/hadoop/hbase/TestMetaTableAccessorNoCluster.java

@@ -41,7 +41,7 @@ import org.apache.hadoop.hbase.shaded.protobuf.generated.ClientProtos.ScanRespon
 import org.apache.hadoop.hbase.testclassification.MediumTests;
 import org.apache.hadoop.hbase.testclassification.MiscTests;
 import org.apache.hadoop.hbase.util.Bytes;
-import org.apache.hadoop.hbase.zookeeper.ZooKeeperWatcher;
+import org.apache.hadoop.hbase.zookeeper.ZKWatcher;
 import org.junit.After;
 import org.junit.Before;
 import org.junit.Test;
@@ -124,7 +124,7 @@ public class TestMetaTableAccessorNoCluster {
   public void testRideOverServerNotRunning()
       throws IOException, InterruptedException, ServiceException {
     // Need a zk watcher.
-    ZooKeeperWatcher zkw = new ZooKeeperWatcher(UTIL.getConfiguration(),
+    ZKWatcher zkw = new ZKWatcher(UTIL.getConfiguration(),
       this.getClass().getSimpleName(), ABORTABLE, true);
     // This is a servername we use in a few places below.
     ServerName sn = ServerName.valueOf("example.com", 1234, System.currentTimeMillis());

hbase-server/src/test/java/org/apache/hadoop/hbase/TestMetaTableLocator.java

@@ -44,7 +44,7 @@ import org.apache.hadoop.hbase.testclassification.MediumTests;
 import org.apache.hadoop.hbase.testclassification.MiscTests;
 import org.apache.hadoop.hbase.util.Threads;
 import org.apache.hadoop.hbase.zookeeper.MetaTableLocator;
-import org.apache.hadoop.hbase.zookeeper.ZooKeeperWatcher;
+import org.apache.hadoop.hbase.zookeeper.ZKWatcher;
 import org.apache.zookeeper.KeeperException;
 import org.junit.After;
 import org.junit.AfterClass;
@@ -66,7 +66,7 @@ public class TestMetaTableLocator {
   private static final HBaseTestingUtility UTIL = new HBaseTestingUtility();
   private static final ServerName SN =
       ServerName.valueOf("example.org", 1234, System.currentTimeMillis());
-  private ZooKeeperWatcher watcher;
+  private ZKWatcher watcher;
   private Abortable abortable;
 
   @BeforeClass public static void beforeClass() throws Exception {
@@ -91,7 +91,7 @@ public class TestMetaTableLocator {
         return false;
       }
     };
-    this.watcher = new ZooKeeperWatcher(UTIL.getConfiguration(),
+    this.watcher = new ZKWatcher(UTIL.getConfiguration(),
       this.getClass().getSimpleName(), this.abortable, true);
   }
 

hbase-server/src/test/java/org/apache/hadoop/hbase/TestZooKeeper.java

@@ -51,7 +51,7 @@ import org.apache.hadoop.hbase.util.Threads;
 import org.apache.hadoop.hbase.zookeeper.EmptyWatcher;
 import org.apache.hadoop.hbase.zookeeper.ZKConfig;
 import org.apache.hadoop.hbase.zookeeper.ZKUtil;
-import org.apache.hadoop.hbase.zookeeper.ZooKeeperWatcher;
+import org.apache.hadoop.hbase.zookeeper.ZKWatcher;
 import org.apache.zookeeper.CreateMode;
 import org.apache.zookeeper.KeeperException;
 import org.apache.zookeeper.ZooDefs;
@@ -184,8 +184,8 @@ public class TestZooKeeper {
    */
   @Test
   public void testCreateWithParents() throws Exception {
-    ZooKeeperWatcher zkw =
+    ZKWatcher zkw =
-        new ZooKeeperWatcher(new Configuration(TEST_UTIL.getConfiguration()),
+        new ZKWatcher(new Configuration(TEST_UTIL.getConfiguration()),
             TestZooKeeper.class.getName(), null);
     byte[] expectedData = new byte[] { 1, 2, 3 };
     ZKUtil.createWithParents(zkw, "/l1/l2/l3/l4/testCreateWithParents", expectedData);
@@ -206,7 +206,7 @@ public class TestZooKeeper {
    */
   @Test
   public void testZNodeDeletes() throws Exception {
-    ZooKeeperWatcher zkw = new ZooKeeperWatcher(
+    ZKWatcher zkw = new ZKWatcher(
       new Configuration(TEST_UTIL.getConfiguration()),
       TestZooKeeper.class.getName(), null);
     ZKUtil.createWithParents(zkw, "/l1/l2/l3/l4");
@@ -247,7 +247,7 @@ public class TestZooKeeper {
 
     // Assumes the  root of the ZooKeeper space is writable as it creates a node
     // wherever the cluster home is defined.
-    ZooKeeperWatcher zk2 = new ZooKeeperWatcher(TEST_UTIL.getConfiguration(),
+    ZKWatcher zk2 = new ZKWatcher(TEST_UTIL.getConfiguration(),
       "testCreateSilentIsReallySilent", null);
 
     // Save the previous ACL
@@ -330,7 +330,7 @@ public class TestZooKeeper {
   @SuppressWarnings("deprecation")
   public void testGetChildDataAndWatchForNewChildrenShouldNotThrowNPE()
       throws Exception {
-    ZooKeeperWatcher zkw = new ZooKeeperWatcher(TEST_UTIL.getConfiguration(), name.getMethodName(), null);
+    ZKWatcher zkw = new ZKWatcher(TEST_UTIL.getConfiguration(), name.getMethodName(), null);
     ZKUtil.getChildDataAndWatchForNewChildren(zkw, "/wrongNode");
   }
 
@@ -345,7 +345,7 @@ public class TestZooKeeper {
     cluster.startRegionServer();
     cluster.waitForActiveAndReadyMaster(10000);
     HMaster m = cluster.getMaster();
-    final ZooKeeperWatcher zkw = m.getZooKeeper();
+    final ZKWatcher zkw = m.getZooKeeper();
     // now the cluster is up. So assign some regions.
     try (Admin admin = TEST_UTIL.getAdmin()) {
       byte[][] SPLIT_KEYS = new byte[][] { Bytes.toBytes("a"), Bytes.toBytes("b"),
@@ -376,14 +376,14 @@ public class TestZooKeeper {
    * Count listeners in zkw excluding listeners, that belongs to workers or other
    * temporary processes.
    */
-  private int countPermanentListeners(ZooKeeperWatcher watcher) {
+  private int countPermanentListeners(ZKWatcher watcher) {
     return countListeners(watcher, ZkSplitLogWorkerCoordination.class);
   }
 
   /**
    * Count listeners in zkw excluding provided classes
    */
-  private int countListeners(ZooKeeperWatcher watcher, Class<?>... exclude) {
+  private int countListeners(ZKWatcher watcher, Class<?>... exclude) {
     int cnt = 0;
     for (Object o : watcher.getListeners()) {
       boolean skip = false;

hbase-server/src/test/java/org/apache/hadoop/hbase/backup/example/TestZooKeeperTableArchiveClient.java

@@ -55,7 +55,7 @@ import org.apache.hadoop.hbase.util.FSUtils;
 import org.apache.hadoop.hbase.util.HFileArchiveUtil;
 import org.apache.hadoop.hbase.util.StoppableImplementation;
 import org.apache.hadoop.hbase.zookeeper.ZKUtil;
-import org.apache.hadoop.hbase.zookeeper.ZooKeeperWatcher;
+import org.apache.hadoop.hbase.zookeeper.ZKWatcher;
 import org.apache.zookeeper.KeeperException;
 import org.junit.After;
 import org.junit.AfterClass;
@@ -93,7 +93,7 @@ public class TestZooKeeperTableArchiveClient {
     CONNECTION = (ClusterConnection)ConnectionFactory.createConnection(UTIL.getConfiguration());
     archivingClient = new ZKTableArchiveClient(UTIL.getConfiguration(), CONNECTION);
     // make hfile archiving node so we can archive files
-    ZooKeeperWatcher watcher = UTIL.getZooKeeperWatcher();
+    ZKWatcher watcher = UTIL.getZooKeeperWatcher();
     String archivingZNode = ZKTableArchiveClient.getArchiveZNode(UTIL.getConfiguration(), watcher);
     ZKUtil.createWithParents(watcher, archivingZNode);
     rss = mock(RegionServerServices.class);

hbase-server/src/test/java/org/apache/hadoop/hbase/client/TestMetaWithReplicas.java

@@ -56,8 +56,8 @@ import org.apache.hadoop.hbase.util.HBaseFsckRepair;
 import org.apache.hadoop.hbase.util.hbck.HbckTestingUtil;
 import org.apache.hadoop.hbase.zookeeper.LoadBalancerTracker;
 import org.apache.hadoop.hbase.zookeeper.ZKUtil;
+import org.apache.hadoop.hbase.zookeeper.ZKWatcher;
 import org.apache.hadoop.hbase.zookeeper.ZNodePaths;
-import org.apache.hadoop.hbase.zookeeper.ZooKeeperWatcher;
 import org.apache.zookeeper.KeeperException;
 import org.junit.After;
 import org.junit.Before;
@@ -132,7 +132,7 @@ public class TestMetaWithReplicas {
   @Test
   public void testZookeeperNodesForReplicas() throws Exception {
     // Checks all the znodes exist when meta's replicas are enabled
-    ZooKeeperWatcher zkw = TEST_UTIL.getZooKeeperWatcher();
+    ZKWatcher zkw = TEST_UTIL.getZooKeeperWatcher();
     Configuration conf = TEST_UTIL.getConfiguration();
     String baseZNode = conf.get(HConstants.ZOOKEEPER_ZNODE_PARENT,
         HConstants.DEFAULT_ZOOKEEPER_ZNODE_PARENT);
@@ -166,7 +166,7 @@ public class TestMetaWithReplicas {
     // server holding the primary meta replica. Then it does a put/get into/from
     // the test table. The put/get operations would use the replicas to locate the
     // location of the test table's region
-    ZooKeeperWatcher zkw = util.getZooKeeperWatcher();
+    ZKWatcher zkw = util.getZooKeeperWatcher();
     Configuration conf = util.getConfiguration();
     conf.setBoolean(HConstants.USE_META_REPLICAS, true);
 
@@ -368,7 +368,7 @@ public class TestMetaWithReplicas {
         false, false);
     HBaseFsckRepair.closeRegionSilentlyAndWait(c,
         rl.getRegionLocation(2).getServerName(), rl.getRegionLocation(2).getRegionInfo());
-    ZooKeeperWatcher zkw = TEST_UTIL.getZooKeeperWatcher();
+    ZKWatcher zkw = TEST_UTIL.getZooKeeperWatcher();
     ZKUtil.deleteNode(zkw, zkw.znodePaths.getZNodeForReplica(2));
     // check that problem exists
     HBaseFsck hbck = doFsck(TEST_UTIL.getConfiguration(), false);
@@ -400,7 +400,7 @@ public class TestMetaWithReplicas {
     // caches update themselves. Uses the master operations to test
     // this
     Configuration conf = TEST_UTIL.getConfiguration();
-    ZooKeeperWatcher zkw = TEST_UTIL.getZooKeeperWatcher();
+    ZKWatcher zkw = TEST_UTIL.getZooKeeperWatcher();
     String baseZNode = conf.get(HConstants.ZOOKEEPER_ZNODE_PARENT,
         HConstants.DEFAULT_ZOOKEEPER_ZNODE_PARENT);
     String primaryMetaZnode = ZNodePaths.joinZNode(baseZNode,

hbase-server/src/test/java/org/apache/hadoop/hbase/client/replication/TestReplicationAdmin.java

@@ -34,17 +34,15 @@ import org.apache.hadoop.hbase.HConstants;
 import org.apache.hadoop.hbase.ReplicationPeerNotFoundException;
 import org.apache.hadoop.hbase.TableName;
 import org.apache.hadoop.hbase.client.Admin;
-import org.apache.hadoop.hbase.client.RetriesExhaustedException;
 import org.apache.hadoop.hbase.replication.ReplicationException;
 import org.apache.hadoop.hbase.replication.ReplicationFactory;
-import org.apache.hadoop.hbase.replication.ReplicationPeer;
 import org.apache.hadoop.hbase.replication.ReplicationPeerConfig;
 import org.apache.hadoop.hbase.replication.ReplicationPeerDescription;
 import org.apache.hadoop.hbase.replication.ReplicationQueues;
 import org.apache.hadoop.hbase.replication.ReplicationQueuesArguments;
 import org.apache.hadoop.hbase.testclassification.ClientTests;
 import org.apache.hadoop.hbase.testclassification.MediumTests;
-import org.apache.hadoop.hbase.zookeeper.ZooKeeperWatcher;
+import org.apache.hadoop.hbase.zookeeper.ZKWatcher;
 import org.junit.AfterClass;
 import org.junit.BeforeClass;
 import org.junit.Rule;
@@ -172,7 +170,7 @@ public class TestReplicationAdmin {
     ReplicationPeerConfig rpc2 = new ReplicationPeerConfig();
     rpc2.setClusterKey(KEY_SECOND);
     Configuration conf = TEST_UTIL.getConfiguration();
-    ZooKeeperWatcher zkw = new ZooKeeperWatcher(conf, "Test HBaseAdmin", null);
+    ZKWatcher zkw = new ZKWatcher(conf, "Test HBaseAdmin", null);
     ReplicationQueues repQueues =
         ReplicationFactory.getReplicationQueues(new ReplicationQueuesArguments(conf, null, zkw));
     repQueues.init("server1");
@@ -187,7 +185,7 @@ public class TestReplicationAdmin {
     }
     repQueues.removeQueue(ID_ONE);
     assertEquals(0, repQueues.getAllQueues().size());
-    
+
     // add recovered queue for ID_ONE
     repQueues.addLog(ID_ONE + "-server2", "file1");
     try {

hbase-server/src/test/java/org/apache/hadoop/hbase/coprocessor/TestMasterCoprocessorExceptionWithAbort.java

@@ -39,8 +39,8 @@ import org.apache.hadoop.hbase.master.MasterCoprocessorHost;
 import org.apache.hadoop.hbase.testclassification.CoprocessorTests;
 import org.apache.hadoop.hbase.testclassification.MediumTests;
 import org.apache.hadoop.hbase.util.Bytes;
-import org.apache.hadoop.hbase.zookeeper.ZooKeeperNodeTracker;
+import org.apache.hadoop.hbase.zookeeper.ZKNodeTracker;
-import org.apache.hadoop.hbase.zookeeper.ZooKeeperWatcher;
+import org.apache.hadoop.hbase.zookeeper.ZKWatcher;
 import org.junit.AfterClass;
 import org.junit.BeforeClass;
 import org.junit.Test;
@@ -60,10 +60,10 @@ import static org.junit.Assert.fail;
 @Category({CoprocessorTests.class, MediumTests.class})
 public class TestMasterCoprocessorExceptionWithAbort {
 
-  public static class MasterTracker extends ZooKeeperNodeTracker {
+  public static class MasterTracker extends ZKNodeTracker {
     public boolean masterZKNodeWasDeleted = false;
 
-    public MasterTracker(ZooKeeperWatcher zkw, String masterNode, Abortable abortable) {
+    public MasterTracker(ZKWatcher zkw, String masterNode, Abortable abortable) {
       super(zkw, masterNode, abortable);
     }
 
@@ -174,7 +174,7 @@ public class TestMasterCoprocessorExceptionWithAbort {
 
     // set a watch on the zookeeper /hbase/master node. If the master dies,
     // the node will be deleted.
-    ZooKeeperWatcher zkw = new ZooKeeperWatcher(UTIL.getConfiguration(),
+    ZKWatcher zkw = new ZKWatcher(UTIL.getConfiguration(),
       "unittest", new Abortable() {
       @Override
       public void abort(String why, Throwable e) {

hbase-server/src/test/java/org/apache/hadoop/hbase/coprocessor/TestMasterCoprocessorExceptionWithRemove.java

@@ -38,8 +38,8 @@ import org.apache.hadoop.hbase.master.MasterCoprocessorHost;
 import org.apache.hadoop.hbase.testclassification.CoprocessorTests;
 import org.apache.hadoop.hbase.testclassification.MediumTests;
 import org.apache.hadoop.hbase.util.Bytes;
-import org.apache.hadoop.hbase.zookeeper.ZooKeeperNodeTracker;
+import org.apache.hadoop.hbase.zookeeper.ZKNodeTracker;
-import org.apache.hadoop.hbase.zookeeper.ZooKeeperWatcher;
+import org.apache.hadoop.hbase.zookeeper.ZKWatcher;
 import org.junit.AfterClass;
 import org.junit.BeforeClass;
 import org.junit.Test;
@@ -59,10 +59,10 @@ import static org.junit.Assert.fail;
 @Category({CoprocessorTests.class, MediumTests.class})
 public class TestMasterCoprocessorExceptionWithRemove {
 
-  public static class MasterTracker extends ZooKeeperNodeTracker {
+  public static class MasterTracker extends ZKNodeTracker {
     public boolean masterZKNodeWasDeleted = false;
 
-    public MasterTracker(ZooKeeperWatcher zkw, String masterNode, Abortable abortable) {
+    public MasterTracker(ZKWatcher zkw, String masterNode, Abortable abortable) {
       super(zkw, masterNode, abortable);
     }
 
@@ -159,7 +159,7 @@ public class TestMasterCoprocessorExceptionWithRemove {
     // we are testing that the default setting of hbase.coprocessor.abortonerror
     // =false
     // is respected.
-    ZooKeeperWatcher zkw = new ZooKeeperWatcher(UTIL.getConfiguration(),
+    ZKWatcher zkw = new ZKWatcher(UTIL.getConfiguration(),
       "unittest", new Abortable() {
       @Override
       public void abort(String why, Throwable e) {

hbase-server/src/test/java/org/apache/hadoop/hbase/master/MockNoopMasterServices.java

@@ -52,7 +52,7 @@ import org.apache.hadoop.hbase.replication.ReplicationException;
 import org.apache.hadoop.hbase.replication.ReplicationPeerConfig;
 import org.apache.hadoop.hbase.replication.ReplicationPeerDescription;
 import org.apache.hadoop.hbase.zookeeper.MetaTableLocator;
-import org.apache.hadoop.hbase.zookeeper.ZooKeeperWatcher;
+import org.apache.hadoop.hbase.zookeeper.ZKWatcher;
 
 import com.google.protobuf.Service;
 
@@ -150,7 +150,7 @@ public class MockNoopMasterServices implements MasterServices, Server {
   }
 
   @Override
-  public ZooKeeperWatcher getZooKeeper() {
+  public ZKWatcher getZooKeeper() {
     return null;
   }
 

hbase-server/src/test/java/org/apache/hadoop/hbase/master/MockRegionServer.java

@@ -25,7 +25,6 @@ import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
 import java.util.Random;
-import java.util.Set;
 import java.util.TreeMap;
 import java.util.concurrent.ConcurrentSkipListMap;
 
@@ -65,7 +64,7 @@ import org.apache.hadoop.hbase.regionserver.throttle.ThroughputController;
 import org.apache.hadoop.hbase.util.Bytes;
 import org.apache.hadoop.hbase.wal.WAL;
 import org.apache.hadoop.hbase.zookeeper.MetaTableLocator;
-import org.apache.hadoop.hbase.zookeeper.ZooKeeperWatcher;
+import org.apache.hadoop.hbase.zookeeper.ZKWatcher;
 import org.apache.zookeeper.KeeperException;
 
 import org.apache.hadoop.hbase.shaded.com.google.protobuf.RpcController;
@@ -138,7 +137,7 @@ import org.apache.hadoop.hbase.shaded.protobuf.generated.QuotaProtos.GetSpaceQuo
 class MockRegionServer implements AdminProtos.AdminService.BlockingInterface,
 ClientProtos.ClientService.BlockingInterface, RegionServerServices {
   private final ServerName sn;
-  private final ZooKeeperWatcher zkw;
+  private final ZKWatcher zkw;
   private final Configuration conf;
   private final Random random = new Random();
 
@@ -191,7 +190,7 @@ ClientProtos.ClientService.BlockingInterface, RegionServerServices {
   throws ZooKeeperConnectionException, IOException {
     this.sn = sn;
     this.conf = conf;
-    this.zkw = new ZooKeeperWatcher(conf, sn.toString(), this, true);
+    this.zkw = new ZKWatcher(conf, sn.toString(), this, true);
   }
 
   /**
@@ -284,7 +283,7 @@ ClientProtos.ClientService.BlockingInterface, RegionServerServices {
   }
 
   @Override
-  public ZooKeeperWatcher getZooKeeper() {
+  public ZKWatcher getZooKeeper() {
     return this.zkw;
   }
 

hbase-server/src/test/java/org/apache/hadoop/hbase/master/TestActiveMasterManager.java

@@ -41,9 +41,9 @@ import org.apache.hadoop.hbase.testclassification.MediumTests;
 import org.apache.hadoop.hbase.zookeeper.ClusterStatusTracker;
 import org.apache.hadoop.hbase.zookeeper.MasterAddressTracker;
 import org.apache.hadoop.hbase.zookeeper.MetaTableLocator;
+import org.apache.hadoop.hbase.zookeeper.ZKListener;
 import org.apache.hadoop.hbase.zookeeper.ZKUtil;
-import org.apache.hadoop.hbase.zookeeper.ZooKeeperListener;
+import org.apache.hadoop.hbase.zookeeper.ZKWatcher;
-import org.apache.hadoop.hbase.zookeeper.ZooKeeperWatcher;
 import org.apache.zookeeper.KeeperException;
 import org.junit.AfterClass;
 import org.junit.BeforeClass;
@@ -70,7 +70,7 @@ public class TestActiveMasterManager {
   }
 
   @Test public void testRestartMaster() throws IOException, KeeperException {
-    ZooKeeperWatcher zk = new ZooKeeperWatcher(TEST_UTIL.getConfiguration(),
+    ZKWatcher zk = new ZKWatcher(TEST_UTIL.getConfiguration(),
       "testActiveMasterManagerFromZK", null, true);
     try {
       ZKUtil.deleteNode(zk, zk.znodePaths.masterAddressZNode);
@@ -112,7 +112,7 @@ public class TestActiveMasterManager {
    */
   @Test
   public void testActiveMasterManagerFromZK() throws Exception {
-    ZooKeeperWatcher zk = new ZooKeeperWatcher(TEST_UTIL.getConfiguration(),
+    ZKWatcher zk = new ZKWatcher(TEST_UTIL.getConfiguration(),
       "testActiveMasterManagerFromZK", null, true);
     try {
       ZKUtil.deleteNode(zk, zk.znodePaths.masterAddressZNode);
@@ -135,7 +135,7 @@ public class TestActiveMasterManager {
     ClusterStatusTracker clusterStatusTracker =
       ms1.getClusterStatusTracker();
     clusterStatusTracker.setClusterUp();
-    activeMasterManager.blockUntilBecomingActiveMaster(100, 
+    activeMasterManager.blockUntilBecomingActiveMaster(100,
         Mockito.mock(MonitoredTask.class));
     assertTrue(activeMasterManager.clusterHasActiveMaster.get());
     assertMaster(zk, firstMasterAddress);
@@ -193,9 +193,9 @@ public class TestActiveMasterManager {
    * @param zk
    * @param thisMasterAddress
    * @throws KeeperException
-   * @throws IOException 
+   * @throws IOException
    */
-  private void assertMaster(ZooKeeperWatcher zk,
+  private void assertMaster(ZKWatcher zk,
       ServerName expectedAddress)
   throws KeeperException, IOException {
     ServerName readAddress = MasterAddressTracker.getMasterAddress(zk);
@@ -209,7 +209,7 @@ public class TestActiveMasterManager {
     DummyMaster dummyMaster;
     boolean isActiveMaster;
 
-    public WaitToBeMasterThread(ZooKeeperWatcher zk, ServerName address) {
+    public WaitToBeMasterThread(ZKWatcher zk, ServerName address) {
       this.dummyMaster = new DummyMaster(zk,address);
       this.manager = this.dummyMaster.getActiveMasterManager();
       isActiveMaster = false;
@@ -224,13 +224,13 @@ public class TestActiveMasterManager {
     }
   }
 
-  public static class NodeDeletionListener extends ZooKeeperListener {
+  public static class NodeDeletionListener extends ZKListener {
     private static final Log LOG = LogFactory.getLog(NodeDeletionListener.class);
 
     private Semaphore lock;
     private String node;
 
-    public NodeDeletionListener(ZooKeeperWatcher watcher, String node) {
+    public NodeDeletionListener(ZKWatcher watcher, String node) {
       super(watcher);
       lock = new Semaphore(0);
       this.node = node;
@@ -257,7 +257,7 @@ public class TestActiveMasterManager {
     private ClusterStatusTracker clusterStatusTracker;
     private ActiveMasterManager activeMasterManager;
 
-    public DummyMaster(ZooKeeperWatcher zk, ServerName master) {
+    public DummyMaster(ZKWatcher zk, ServerName master) {
       this.clusterStatusTracker =
         new ClusterStatusTracker(zk, this);
       clusterStatusTracker.start();
@@ -269,7 +269,7 @@ public class TestActiveMasterManager {
 
     @Override
     public void abort(final String msg, final Throwable t) {}
-    
+
     @Override
     public boolean isAborted() {
       return false;
@@ -281,7 +281,7 @@ public class TestActiveMasterManager {
     }
 
     @Override
-    public ZooKeeperWatcher getZooKeeper() {
+    public ZKWatcher getZooKeeper() {
       return null;
     }
 

hbase-server/src/test/java/org/apache/hadoop/hbase/master/TestAssignmentListener.java

@@ -47,11 +47,9 @@ import org.apache.hadoop.hbase.testclassification.MasterTests;
 import org.apache.hadoop.hbase.testclassification.MediumTests;
 import org.apache.hadoop.hbase.util.Bytes;
 import org.apache.hadoop.hbase.util.JVMClusterUtil;
-import org.apache.hadoop.hbase.zookeeper.DrainingServerTracker;
-import org.apache.hadoop.hbase.zookeeper.RegionServerTracker;
 import org.apache.hadoop.hbase.zookeeper.ZKUtil;
+import org.apache.hadoop.hbase.zookeeper.ZKWatcher;
 import org.apache.hadoop.hbase.zookeeper.ZNodePaths;
-import org.apache.hadoop.hbase.zookeeper.ZooKeeperWatcher;
 import org.junit.AfterClass;
 import org.junit.Assert;
 import org.junit.BeforeClass;
@@ -319,7 +317,7 @@ public class TestAssignmentListener {
     // are properly added to the ServerManager.drainingServers when they
     // register with the ServerManager under these circumstances.
     Configuration conf = TEST_UTIL.getConfiguration();
-    ZooKeeperWatcher zooKeeper = new ZooKeeperWatcher(conf,
+    ZKWatcher zooKeeper = new ZKWatcher(conf,
         "zkWatcher-NewServerDrainTest", abortable, true);
     String baseZNode = conf.get(HConstants.ZOOKEEPER_ZNODE_PARENT,
         HConstants.DEFAULT_ZOOKEEPER_ZNODE_PARENT);

hbase-server/src/test/java/org/apache/hadoop/hbase/master/TestClockSkewDetection.java

@@ -27,19 +27,13 @@ import java.net.InetAddress;
 import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
 import org.apache.hadoop.conf.Configuration;
-import org.apache.hadoop.hbase.ChoreService;
 import org.apache.hadoop.hbase.ClockOutOfSyncException;
-import org.apache.hadoop.hbase.CoordinatedStateManager;
 import org.apache.hadoop.hbase.HBaseConfiguration;
-import org.apache.hadoop.hbase.Server;
-import org.apache.hadoop.hbase.ServerName;
 import org.apache.hadoop.hbase.client.ClusterConnection;
 import org.apache.hadoop.hbase.ipc.RpcControllerFactory;
 import org.apache.hadoop.hbase.shaded.protobuf.generated.RegionServerStatusProtos.RegionServerStartupRequest;
 import org.apache.hadoop.hbase.testclassification.MasterTests;
 import org.apache.hadoop.hbase.testclassification.SmallTests;
-import org.apache.hadoop.hbase.zookeeper.MetaTableLocator;
-import org.apache.hadoop.hbase.zookeeper.ZooKeeperWatcher;
 import org.junit.Test;
 import org.junit.experimental.categories.Category;
 

hbase-server/src/test/java/org/apache/hadoop/hbase/master/TestDistributedLogSplitting.java

@@ -41,7 +41,6 @@ import java.util.concurrent.Executors;
 import java.util.concurrent.Future;
 import java.util.concurrent.TimeUnit;
 import java.util.concurrent.TimeoutException;
-import java.util.concurrent.atomic.AtomicLong;
 import java.util.concurrent.atomic.LongAdder;
 
 import org.apache.commons.logging.Log;
@@ -93,8 +92,7 @@ import org.apache.hadoop.hbase.wal.WALKey;
 import org.apache.hadoop.hbase.wal.WALSplitter;
 import org.apache.hadoop.hbase.zookeeper.MiniZooKeeperCluster;
 import org.apache.hadoop.hbase.zookeeper.ZKUtil;
-import org.apache.hadoop.hbase.zookeeper.ZooKeeperWatcher;
+import org.apache.hadoop.hbase.zookeeper.ZKWatcher;
-import org.apache.hadoop.hdfs.MiniDFSCluster;
 import org.junit.After;
 import org.junit.AfterClass;
 import org.junit.Before;
@@ -210,7 +208,7 @@ public class TestDistributedLogSplitting {
     Path rootdir = FSUtils.getRootDir(conf);
 
     int numRegions = 50;
-    Table t = installTable(new ZooKeeperWatcher(conf, "table-creation", null),
+    Table t = installTable(new ZKWatcher(conf, "table-creation", null),
         "table", "family", numRegions);
     try {
       TableName table = t.getName();
@@ -283,7 +281,7 @@ public class TestDistributedLogSplitting {
     // they will consume recovered.edits
     master.balanceSwitch(false);
 
-    final ZooKeeperWatcher zkw = new ZooKeeperWatcher(conf, "table-creation", null);
+    final ZKWatcher zkw = new ZKWatcher(conf, "table-creation", null);
     Table ht = installTable(zkw, "table", "family", NUM_REGIONS_TO_CREATE);
     try {
       HRegionServer hrs = findRSToKill(false, "table");
@@ -352,7 +350,7 @@ public class TestDistributedLogSplitting {
     final Path logDir = new Path(rootdir,
       AbstractFSWALProvider.getWALDirectoryName(hrs.getServerName().toString()));
 
-    Table t = installTable(new ZooKeeperWatcher(conf, "table-creation", null),
+    Table t = installTable(new ZKWatcher(conf, "table-creation", null),
         "table", "family", 40);
     try {
       makeWAL(hrs, ProtobufUtil.getOnlineRegions(hrs.getRSRpcServices()),
@@ -407,7 +405,7 @@ public class TestDistributedLogSplitting {
 
     startCluster(NUM_RS); // NUM_RS=6.
 
-    final ZooKeeperWatcher zkw = new ZooKeeperWatcher(conf,
+    final ZKWatcher zkw = new ZKWatcher(conf,
         "distributed log splitting test", null);
 
     Table ht = installTable(zkw, "table", "family", NUM_REGIONS_TO_CREATE);
@@ -520,7 +518,7 @@ public class TestDistributedLogSplitting {
   public void testReadWriteSeqIdFiles() throws Exception {
     LOG.info("testReadWriteSeqIdFiles");
     startCluster(2);
-    final ZooKeeperWatcher zkw = new ZooKeeperWatcher(conf, "table-creation", null);
+    final ZKWatcher zkw = new ZKWatcher(conf, "table-creation", null);
     Table ht = installTable(zkw, name.getMethodName(), "family", 10);
     try {
       FileSystem fs = master.getMasterFileSystem().getFileSystem();
@@ -551,12 +549,12 @@ public class TestDistributedLogSplitting {
     }
   }
 
-  Table installTable(ZooKeeperWatcher zkw, String tname, String fname, int nrs) throws Exception {
+  Table installTable(ZKWatcher zkw, String tname, String fname, int nrs) throws Exception {
     return installTable(zkw, tname, fname, nrs, 0);
   }
 
-  Table installTable(ZooKeeperWatcher zkw, String tname, String fname, int nrs,
+  Table installTable(ZKWatcher zkw, String tname, String fname, int nrs,
-      int existingRegions) throws Exception {
+                     int existingRegions) throws Exception {
     // Create a table with regions
     TableName table = TableName.valueOf(tname);
     byte [] family = Bytes.toBytes(fname);
@@ -737,7 +735,7 @@ public class TestDistributedLogSplitting {
     return count;
   }
 
-  private void blockUntilNoRIT(ZooKeeperWatcher zkw, HMaster master) throws Exception {
+  private void blockUntilNoRIT(ZKWatcher zkw, HMaster master) throws Exception {
     TEST_UTIL.waitUntilNoRegionsInTransition(60000);
   }
 

hbase-server/src/test/java/org/apache/hadoop/hbase/master/TestHMasterRPCException.java

@@ -39,7 +39,7 @@ import org.apache.hadoop.hbase.testclassification.MasterTests;
 import org.apache.hadoop.hbase.testclassification.MediumTests;
 import org.apache.hadoop.hbase.util.Bytes;
 import org.apache.hadoop.hbase.zookeeper.ZKUtil;
-import org.apache.hadoop.hbase.zookeeper.ZooKeeperWatcher;
+import org.apache.hadoop.hbase.zookeeper.ZKWatcher;
 import org.apache.zookeeper.KeeperException;
 import org.junit.After;
 import org.junit.Before;
@@ -66,7 +66,7 @@ public class TestHMasterRPCException {
     conf.setInt(HConstants.ZK_SESSION_TIMEOUT, 2000);
     testUtil.startMiniZKCluster();
 
-    ZooKeeperWatcher watcher = testUtil.getZooKeeperWatcher();
+    ZKWatcher watcher = testUtil.getZooKeeperWatcher();
     ZKUtil.createWithParents(watcher, watcher.znodePaths.masterAddressZNode, Bytes.toBytes("fake:123"));
     master = new HMaster(conf);
     rpcClient = RpcClientFactory.createClient(conf, HConstants.CLUSTER_ID_DEFAULT);

hbase-server/src/test/java/org/apache/hadoop/hbase/master/TestMasterNoCluster.java

@@ -53,7 +53,7 @@ import org.apache.hadoop.hbase.util.FSUtils;
 import org.apache.hadoop.hbase.util.Threads;
 import org.apache.hadoop.hbase.zookeeper.MetaTableLocator;
 import org.apache.hadoop.hbase.zookeeper.ZKUtil;
-import org.apache.hadoop.hbase.zookeeper.ZooKeeperWatcher;
+import org.apache.hadoop.hbase.zookeeper.ZKWatcher;
 import org.apache.hadoop.metrics2.lib.DefaultMetricsSystem;
 import org.apache.zookeeper.KeeperException;
 import org.junit.After;
@@ -105,7 +105,7 @@ public class TestMasterNoCluster {
   public void tearDown()
   throws KeeperException, ZooKeeperConnectionException, IOException {
     // Make sure zk is clean before we run the next test.
-    ZooKeeperWatcher zkw = new ZooKeeperWatcher(TESTUTIL.getConfiguration(),
+    ZKWatcher zkw = new ZKWatcher(TESTUTIL.getConfiguration(),
         "@Before", new Abortable() {
       @Override
       public void abort(String why, Throwable e) {

hbase-server/src/test/java/org/apache/hadoop/hbase/master/TestMasterStatusServlet.java

@@ -41,8 +41,8 @@ import org.apache.hadoop.hbase.testclassification.MediumTests;
 import org.apache.hadoop.hbase.tmpl.master.MasterStatusTmpl;
 import org.apache.hadoop.hbase.util.Bytes;
 import org.apache.hadoop.hbase.zookeeper.MasterAddressTracker;
+import org.apache.hadoop.hbase.zookeeper.ZKWatcher;
 import org.apache.hadoop.hbase.zookeeper.ZNodePaths;
-import org.apache.hadoop.hbase.zookeeper.ZooKeeperWatcher;
 import org.junit.Before;
 import org.junit.Test;
 import org.junit.experimental.categories.Category;
@@ -95,7 +95,7 @@ public class TestMasterStatusServlet {
     Mockito.doReturn(serverManager).when(master).getServerManager();
 
     // Fake ZKW
-    ZooKeeperWatcher zkw = Mockito.mock(ZooKeeperWatcher.class);
+    ZKWatcher zkw = Mockito.mock(ZKWatcher.class);
     Mockito.doReturn(new ZNodePaths(conf)).when(zkw).getZNodePaths();
     Mockito.doReturn("fakequorum").when(zkw).getQuorum();
     Mockito.doReturn(zkw).when(master).getZooKeeper();

hbase-server/src/test/java/org/apache/hadoop/hbase/master/TestSplitLogManager.java

@@ -61,7 +61,7 @@ import org.apache.hadoop.hbase.testclassification.MasterTests;
 import org.apache.hadoop.hbase.testclassification.MediumTests;
 import org.apache.hadoop.hbase.zookeeper.ZKSplitLog;
 import org.apache.hadoop.hbase.zookeeper.ZKUtil;
-import org.apache.hadoop.hbase.zookeeper.ZooKeeperWatcher;
+import org.apache.hadoop.hbase.zookeeper.ZKWatcher;
 import org.apache.log4j.Level;
 import org.apache.log4j.Logger;
 import org.apache.zookeeper.CreateMode;
@@ -84,7 +84,7 @@ public class TestSplitLogManager {
     Logger.getLogger("org.apache.hadoop.hbase").setLevel(Level.DEBUG);
   }
 
-  private ZooKeeperWatcher zkw;
+  private ZKWatcher zkw;
   private DummyMasterServices master;
   private SplitLogManager slm;
   private Configuration conf;
@@ -93,17 +93,17 @@ public class TestSplitLogManager {
   private static HBaseTestingUtility TEST_UTIL;
 
   class DummyMasterServices extends MockNoopMasterServices {
-    private ZooKeeperWatcher zkw;
+    private ZKWatcher zkw;
     private CoordinatedStateManager cm;
 
-    public DummyMasterServices(ZooKeeperWatcher zkw, Configuration conf) {
+    public DummyMasterServices(ZKWatcher zkw, Configuration conf) {
       super(conf);
       this.zkw = zkw;
       cm = new ZkCoordinatedStateManager(this);
     }
 
     @Override
-    public ZooKeeperWatcher getZooKeeper() {
+    public ZKWatcher getZooKeeper() {
       return zkw;
     }
 
@@ -125,7 +125,7 @@ public class TestSplitLogManager {
     conf = TEST_UTIL.getConfiguration();
     // Use a different ZK wrapper instance for each tests.
     zkw =
-        new ZooKeeperWatcher(conf, "split-log-manager-tests" + UUID.randomUUID().toString(), null);
+        new ZKWatcher(conf, "split-log-manager-tests" + UUID.randomUUID().toString(), null);
     master = new DummyMasterServices(zkw, conf);
 
     ZKUtil.deleteChildrenRecursively(zkw, zkw.znodePaths.baseZNode);

hbase-server/src/test/java/org/apache/hadoop/hbase/master/TestTableStateManager.java

@@ -29,8 +29,8 @@ import org.apache.hadoop.hbase.shaded.protobuf.generated.ZooKeeperProtos;
 import org.apache.hadoop.hbase.testclassification.LargeTests;
 import org.apache.hadoop.hbase.testclassification.MasterTests;
 import org.apache.hadoop.hbase.zookeeper.ZKUtil;
+import org.apache.hadoop.hbase.zookeeper.ZKWatcher;
 import org.apache.hadoop.hbase.zookeeper.ZNodePaths;
-import org.apache.hadoop.hbase.zookeeper.ZooKeeperWatcher;
 import org.apache.zookeeper.KeeperException;
 import org.junit.After;
 import org.junit.Assert;
@@ -60,7 +60,7 @@ public class TestTableStateManager {
     final TableName tableName = TableName.valueOf(name.getMethodName());
     TEST_UTIL.startMiniCluster(2, 1);
     TEST_UTIL.shutdownMiniHBaseCluster();
-    ZooKeeperWatcher watcher = TEST_UTIL.getZooKeeperWatcher();
+    ZKWatcher watcher = TEST_UTIL.getZooKeeperWatcher();
     setTableStateInZK(watcher, tableName, ZooKeeperProtos.DeprecatedTableState.State.DISABLED);
     TEST_UTIL.restartHBaseCluster(1);
 
@@ -70,8 +70,8 @@ public class TestTableStateManager {
         TableState.State.DISABLED);
   }
 
-  private void setTableStateInZK(ZooKeeperWatcher watcher, final TableName tableName,
+  private void setTableStateInZK(ZKWatcher watcher, final TableName tableName,
-      final ZooKeeperProtos.DeprecatedTableState.State state)
+                                 final ZooKeeperProtos.DeprecatedTableState.State state)
       throws KeeperException, IOException {
     String znode = ZNodePaths.joinZNode(watcher.znodePaths.tableZNode, tableName.getNameAsString());
     if (ZKUtil.checkExists(watcher, znode) == -1) {

hbase-server/src/test/java/org/apache/hadoop/hbase/master/cleaner/TestHFileCleaner.java

@@ -44,7 +44,7 @@ import org.apache.hadoop.hbase.testclassification.MediumTests;
 import org.apache.hadoop.hbase.util.EnvironmentEdge;
 import org.apache.hadoop.hbase.util.EnvironmentEdgeManager;
 import org.apache.hadoop.hbase.zookeeper.MetaTableLocator;
-import org.apache.hadoop.hbase.zookeeper.ZooKeeperWatcher;
+import org.apache.hadoop.hbase.zookeeper.ZKWatcher;
 import org.junit.AfterClass;
 import org.junit.Assert;
 import org.junit.BeforeClass;
@@ -205,9 +205,9 @@ public class TestHFileCleaner {
     }
 
     @Override
-    public ZooKeeperWatcher getZooKeeper() {
+    public ZKWatcher getZooKeeper() {
       try {
-        return new ZooKeeperWatcher(getConfiguration(), "dummy server", this);
+        return new ZKWatcher(getConfiguration(), "dummy server", this);
       } catch (IOException e) {
         e.printStackTrace();
       }

hbase-server/src/test/java/org/apache/hadoop/hbase/master/cleaner/TestHFileLinkCleaner.java

@@ -42,7 +42,7 @@ import org.apache.hadoop.hbase.testclassification.MediumTests;
 import org.apache.hadoop.hbase.util.FSUtils;
 import org.apache.hadoop.hbase.util.HFileArchiveUtil;
 import org.apache.hadoop.hbase.zookeeper.MetaTableLocator;
-import org.apache.hadoop.hbase.zookeeper.ZooKeeperWatcher;
+import org.apache.hadoop.hbase.zookeeper.ZKWatcher;
 import org.junit.Rule;
 import org.junit.Test;
 import org.junit.experimental.categories.Category;
@@ -146,9 +146,9 @@ public class TestHFileLinkCleaner {
     }
 
     @Override
-    public ZooKeeperWatcher getZooKeeper() {
+    public ZKWatcher getZooKeeper() {
       try {
-        return new ZooKeeperWatcher(getConfiguration(), "dummy server", this);
+        return new ZKWatcher(getConfiguration(), "dummy server", this);
       } catch (IOException e) {
         e.printStackTrace();
       }

hbase-server/src/test/java/org/apache/hadoop/hbase/master/cleaner/TestLogsCleaner.java

@@ -57,7 +57,7 @@ import org.apache.hadoop.hbase.testclassification.MasterTests;
 import org.apache.hadoop.hbase.testclassification.MediumTests;
 import org.apache.hadoop.hbase.zookeeper.MetaTableLocator;
 import org.apache.hadoop.hbase.zookeeper.RecoverableZooKeeper;
-import org.apache.hadoop.hbase.zookeeper.ZooKeeperWatcher;
+import org.apache.hadoop.hbase.zookeeper.ZKWatcher;
 import org.apache.zookeeper.KeeperException;
 import org.apache.zookeeper.data.Stat;
 import org.junit.AfterClass;
@@ -234,7 +234,7 @@ public class TestLogsCleaner {
 
     // when zk is working both files should be returned
     cleaner = new ReplicationLogCleaner();
-    try (ZooKeeperWatcher zkw = new ZooKeeperWatcher(conf, "testZooKeeperAbort-normal", null)) {
+    try (ZKWatcher zkw = new ZKWatcher(conf, "testZooKeeperAbort-normal", null)) {
       cleaner.setConf(conf, zkw);
       cleaner.preClean();
       Iterable<FileStatus> filesToDelete = cleaner.getDeletableFiles(dummyFiles);
@@ -255,9 +255,9 @@ public class TestLogsCleaner {
     }
 
     @Override
-    public ZooKeeperWatcher getZooKeeper() {
+    public ZKWatcher getZooKeeper() {
       try {
-        return new ZooKeeperWatcher(getConfiguration(), "dummy server", this);
+        return new ZKWatcher(getConfiguration(), "dummy server", this);
       } catch (IOException e) {
         e.printStackTrace();
       }
@@ -321,7 +321,7 @@ public class TestLogsCleaner {
     }
   }
 
-  static class FaultyZooKeeperWatcher extends ZooKeeperWatcher {
+  static class FaultyZooKeeperWatcher extends ZKWatcher {
     private RecoverableZooKeeper zk;
 
     public FaultyZooKeeperWatcher(Configuration conf, String identifier, Abortable abortable)

hbase-server/src/test/java/org/apache/hadoop/hbase/master/cleaner/TestReplicationHFileCleaner.java

@@ -55,7 +55,7 @@ import org.apache.hadoop.hbase.testclassification.SmallTests;
 import org.apache.hadoop.hbase.util.Pair;
 import org.apache.hadoop.hbase.zookeeper.MetaTableLocator;
 import org.apache.hadoop.hbase.zookeeper.RecoverableZooKeeper;
-import org.apache.hadoop.hbase.zookeeper.ZooKeeperWatcher;
+import org.apache.hadoop.hbase.zookeeper.ZKWatcher;
 import org.apache.zookeeper.KeeperException;
 import org.apache.zookeeper.data.Stat;
 import org.junit.After;
@@ -240,7 +240,7 @@ public class TestReplicationHFileCleaner {
 
     // when zk is working both files should be returned
     cleaner = new ReplicationHFileCleaner();
-    ZooKeeperWatcher zkw = new ZooKeeperWatcher(conf, "testZooKeeperAbort-normal", null);
+    ZKWatcher zkw = new ZKWatcher(conf, "testZooKeeperAbort-normal", null);
     try {
       cleaner.setConf(conf, zkw);
       Iterable<FileStatus> filesToDelete = cleaner.getDeletableFiles(dummyFiles);
@@ -263,9 +263,9 @@ public class TestReplicationHFileCleaner {
     }
 
     @Override
-    public ZooKeeperWatcher getZooKeeper() {
+    public ZKWatcher getZooKeeper() {
       try {
-        return new ZooKeeperWatcher(getConfiguration(), "dummy server", this);
+        return new ZKWatcher(getConfiguration(), "dummy server", this);
       } catch (IOException e) {
         e.printStackTrace();
       }
@@ -332,7 +332,7 @@ public class TestReplicationHFileCleaner {
     }
   }
 
-  static class FaultyZooKeeperWatcher extends ZooKeeperWatcher {
+  static class FaultyZooKeeperWatcher extends ZKWatcher {
     private RecoverableZooKeeper zk;
     public FaultyZooKeeperWatcher(Configuration conf, String identifier, Abortable abortable)
         throws ZooKeeperConnectionException, IOException {

hbase-server/src/test/java/org/apache/hadoop/hbase/master/cleaner/TestReplicationZKNodeCleaner.java

@@ -32,7 +32,7 @@ import org.apache.hadoop.hbase.replication.ReplicationQueuesArguments;
 import org.apache.hadoop.hbase.replication.ReplicationQueuesZKImpl;
 import org.apache.hadoop.hbase.testclassification.MasterTests;
 import org.apache.hadoop.hbase.testclassification.MediumTests;
-import org.apache.hadoop.hbase.zookeeper.ZooKeeperWatcher;
+import org.apache.hadoop.hbase.zookeeper.ZKWatcher;
 import org.junit.AfterClass;
 import org.junit.BeforeClass;
 import org.junit.Test;
@@ -48,12 +48,12 @@ public class TestReplicationZKNodeCleaner {
   private final String SERVER_TWO = "server2";
 
   private final Configuration conf;
-  private final ZooKeeperWatcher zkw;
+  private final ZKWatcher zkw;
   private final ReplicationQueues repQueues;
 
   public TestReplicationZKNodeCleaner() throws Exception {
     conf = TEST_UTIL.getConfiguration();
-    zkw = new ZooKeeperWatcher(conf, "TestReplicationZKNodeCleaner", null);
+    zkw = new ZKWatcher(conf, "TestReplicationZKNodeCleaner", null);
     repQueues = ReplicationFactory.getReplicationQueues(new ReplicationQueuesArguments(conf, null,
         zkw));
     assertTrue(repQueues instanceof ReplicationQueuesZKImpl);

hbase-server/src/test/java/org/apache/hadoop/hbase/procedure/SimpleRSProcedureManager.java

@@ -35,7 +35,7 @@ import org.apache.hadoop.conf.Configuration;
 import org.apache.hadoop.hbase.Abortable;
 import org.apache.hadoop.hbase.DaemonThreadFactory;
 import org.apache.hadoop.hbase.regionserver.RegionServerServices;
-import org.apache.hadoop.hbase.zookeeper.ZooKeeperWatcher;
+import org.apache.hadoop.hbase.zookeeper.ZKWatcher;
 import org.apache.hadoop.hbase.errorhandling.ForeignException;
 import org.apache.hadoop.hbase.errorhandling.ForeignExceptionDispatcher;
 import org.apache.zookeeper.KeeperException;
@@ -51,7 +51,7 @@ public class SimpleRSProcedureManager extends RegionServerProcedureManager {
   @Override
   public void initialize(RegionServerServices rss) throws KeeperException {
     this.rss = rss;
-    ZooKeeperWatcher zkw = rss.getZooKeeper();
+    ZKWatcher zkw = rss.getZooKeeper();
     this.memberRpcs = new ZKProcedureMemberRpcs(zkw, getProcedureSignature());
 
     ThreadPoolExecutor pool =

hbase-server/src/test/java/org/apache/hadoop/hbase/procedure/TestZKProcedure.java

@@ -45,7 +45,7 @@ import org.apache.hadoop.hbase.errorhandling.ForeignExceptionDispatcher;
 import org.apache.hadoop.hbase.errorhandling.TimeoutException;
 import org.apache.hadoop.hbase.procedure.Subprocedure.SubprocedureImpl;
 import org.apache.hadoop.hbase.util.Pair;
-import org.apache.hadoop.hbase.zookeeper.ZooKeeperWatcher;
+import org.apache.hadoop.hbase.zookeeper.ZKWatcher;
 import org.junit.AfterClass;
 import org.junit.BeforeClass;
 import org.junit.Test;
@@ -85,8 +85,8 @@ public class TestZKProcedure {
     UTIL.shutdownMiniZKCluster();
   }
 
-  private static ZooKeeperWatcher newZooKeeperWatcher() throws IOException {
+  private static ZKWatcher newZooKeeperWatcher() throws IOException {
-    return new ZooKeeperWatcher(UTIL.getConfiguration(), "testing utility", new Abortable() {
+    return new ZKWatcher(UTIL.getConfiguration(), "testing utility", new Abortable() {
       @Override
       public void abort(String why, Throwable e) {
         throw new RuntimeException(
@@ -123,7 +123,7 @@ public class TestZKProcedure {
     List<String> expected = Arrays.asList(members);
 
     // setup the constants
-    ZooKeeperWatcher coordZkw = newZooKeeperWatcher();
+    ZKWatcher coordZkw = newZooKeeperWatcher();
     String opDescription = "coordination test - " + members.length + " cohort members";
 
     // start running the controller
@@ -144,7 +144,7 @@ public class TestZKProcedure {
     List<Pair<ProcedureMember, ZKProcedureMemberRpcs>> procMembers = new ArrayList<>(members.length);
     // start each member
     for (String member : members) {
-      ZooKeeperWatcher watcher = newZooKeeperWatcher();
+      ZKWatcher watcher = newZooKeeperWatcher();
       ZKProcedureMemberRpcs comms = new ZKProcedureMemberRpcs(watcher, opDescription);
       ThreadPoolExecutor pool2 = ProcedureMember.defaultPool(member, 1, KEEP_ALIVE);
       ProcedureMember procMember = new ProcedureMember(comms, pool2, subprocFactory);
@@ -207,7 +207,7 @@ public class TestZKProcedure {
     final CountDownLatch coordinatorReceivedErrorLatch = new CountDownLatch(1);
 
     // start running the coordinator and its controller
-    ZooKeeperWatcher coordinatorWatcher = newZooKeeperWatcher();
+    ZKWatcher coordinatorWatcher = newZooKeeperWatcher();
     ZKProcedureCoordinator coordinatorController = new ZKProcedureCoordinator(
         coordinatorWatcher, opDescription, COORDINATOR_NODE_NAME);
     ThreadPoolExecutor pool = ProcedureCoordinator.defaultPool(COORDINATOR_NODE_NAME, POOL_SIZE, KEEP_ALIVE);
@@ -217,7 +217,7 @@ public class TestZKProcedure {
     SubprocedureFactory subprocFactory = Mockito.mock(SubprocedureFactory.class);
     List<Pair<ProcedureMember, ZKProcedureMemberRpcs>> members = new ArrayList<>(expected.size());
     for (String member : expected) {
-      ZooKeeperWatcher watcher = newZooKeeperWatcher();
+      ZKWatcher watcher = newZooKeeperWatcher();
       ZKProcedureMemberRpcs controller = new ZKProcedureMemberRpcs(watcher, opDescription);
       ThreadPoolExecutor pool2 = ProcedureMember.defaultPool(member, 1, KEEP_ALIVE);
       ProcedureMember mem = new ProcedureMember(controller, pool2, subprocFactory);

hbase-server/src/test/java/org/apache/hadoop/hbase/procedure/TestZKProcedureControllers.java

@@ -37,7 +37,7 @@ import org.apache.hadoop.hbase.testclassification.MasterTests;
 import org.apache.hadoop.hbase.testclassification.MediumTests;
 import org.apache.hadoop.hbase.util.Pair;
 import org.apache.hadoop.hbase.zookeeper.ZKUtil;
-import org.apache.hadoop.hbase.zookeeper.ZooKeeperWatcher;
+import org.apache.hadoop.hbase.zookeeper.ZKWatcher;
 import org.junit.AfterClass;
 import org.junit.BeforeClass;
 import org.junit.Test;
@@ -79,7 +79,7 @@ public class TestZKProcedureControllers {
    */
   @Test(timeout = 60000)
   public void testSimpleZKCohortMemberController() throws Exception {
-    ZooKeeperWatcher watcher = UTIL.getZooKeeperWatcher();
+    ZKWatcher watcher = UTIL.getZooKeeperWatcher();
     final String operationName = "instanceTest";
 
     final Subprocedure sub = Mockito.mock(Subprocedure.class);
@@ -171,7 +171,7 @@ public class TestZKProcedureControllers {
 
   private void runMockCommitWithOrchestratedControllers(StartControllers controllers,
       String operationName, byte[] data, String... cohort) throws Exception {
-    ZooKeeperWatcher watcher = UTIL.getZooKeeperWatcher();
+    ZKWatcher watcher = UTIL.getZooKeeperWatcher();
     List<String> expected = Lists.newArrayList(cohort);
 
     final Subprocedure sub = Mockito.mock(Subprocedure.class);
@@ -247,7 +247,7 @@ public class TestZKProcedureControllers {
 
   public void runEarlyPrepareNodes(StartControllers controllers, String operationName, byte[] data,
       String... cohort) throws Exception {
-    ZooKeeperWatcher watcher = UTIL.getZooKeeperWatcher();
+    ZKWatcher watcher = UTIL.getZooKeeperWatcher();
     List<String> expected = Lists.newArrayList(cohort);
 
     final Subprocedure sub = Mockito.mock(Subprocedure.class);
@@ -344,7 +344,7 @@ public class TestZKProcedureControllers {
   /**
    * Verify that the prepare, commit and abort nodes for the operation are removed from zookeeper
    */
-  private void verifyZooKeeperClean(String operationName, ZooKeeperWatcher watcher,
+  private void verifyZooKeeperClean(String operationName, ZKWatcher watcher,
       ZKProcedureUtil controller) throws Exception {
     String prepare = ZKProcedureUtil.getAcquireBarrierNode(controller, operationName);
     String commit = ZKProcedureUtil.getReachedBarrierNode(controller, operationName);
@@ -383,18 +383,18 @@ public class TestZKProcedureControllers {
    */
   private abstract class StartControllers {
     public abstract Pair<ZKProcedureCoordinator, List<ZKProcedureMemberRpcs>> start(
-        ZooKeeperWatcher watcher, String operationName,
+            ZKWatcher watcher, String operationName,
-        ProcedureCoordinator coordinator, String controllerName,
+            ProcedureCoordinator coordinator, String controllerName,
-        ProcedureMember member, List<String> cohortNames) throws Exception;
+            ProcedureMember member, List<String> cohortNames) throws Exception;
   }
 
   private final StartControllers startCoordinatorFirst = new StartControllers() {
 
     @Override
     public Pair<ZKProcedureCoordinator, List<ZKProcedureMemberRpcs>> start(
-        ZooKeeperWatcher watcher, String operationName,
+            ZKWatcher watcher, String operationName,
-        ProcedureCoordinator coordinator, String controllerName,
+            ProcedureCoordinator coordinator, String controllerName,
-        ProcedureMember member, List<String> expected) throws Exception {
+            ProcedureMember member, List<String> expected) throws Exception {
       // start the controller
       ZKProcedureCoordinator controller = new ZKProcedureCoordinator(
           watcher, operationName, CONTROLLER_NODE_NAME);
@@ -420,9 +420,9 @@ public class TestZKProcedureControllers {
 
     @Override
     public Pair<ZKProcedureCoordinator, List<ZKProcedureMemberRpcs>> start(
-        ZooKeeperWatcher watcher, String operationName,
+            ZKWatcher watcher, String operationName,
-        ProcedureCoordinator coordinator, String controllerName,
+            ProcedureCoordinator coordinator, String controllerName,
-        ProcedureMember member, List<String> expected) throws Exception {
+            ProcedureMember member, List<String> expected) throws Exception {
 
       // make a cohort controller for each expected node
       List<ZKProcedureMemberRpcs> cohortControllers = new ArrayList<>();