HBASE-19498 Fix findbugs and error-prone warnings in hbase-client (branch-2)

Signed-off-by: Michael Stack <stack@apache.org>
Signed-off-by: Apekshit Sharma <appy@apache.org>

hbase-client/src/main/java/org/apache/hadoop/hbase/ClusterStatus.java

@@ -185,7 +185,7 @@ public class ClusterStatus {
     int count = 0;
     if (liveServers != null && !liveServers.isEmpty()) {
       for (Map.Entry<ServerName, ServerLoad> e: this.liveServers.entrySet()) {
-        count += e.getValue().getNumberOfRegions();
+        count = count + e.getValue().getNumberOfRegions();
       }
     }
     return count;
@@ -217,9 +217,7 @@ public class ClusterStatus {
     return hbaseVersion;
   }
 
-  /**
+  @Override
-   * @see java.lang.Object#equals(java.lang.Object)
-   */
   public boolean equals(Object o) {
     if (this == o) {
       return true;
@@ -238,16 +236,13 @@ public class ClusterStatus {
       getMasterInfoPort() == other.getMasterInfoPort();
   }
 
-  /**
+  @Override
-   * @see java.lang.Object#hashCode()
-   */
   public int hashCode() {
     return Objects.hashCode(hbaseVersion, liveServers, deadServers, master, backupMasters,
       clusterId, masterInfoPort);
   }
 
   /**
-   *
    * @return the object version number
    * @deprecated As of release 2.0.0, this will be removed in HBase 3.0.0
    */
@@ -352,6 +347,7 @@ public class ClusterStatus {
     return masterInfoPort;
   }
 
+  @Override
   public String toString() {
     StringBuilder sb = new StringBuilder(1024);
     sb.append("Master: " + master);

hbase-client/src/main/java/org/apache/hadoop/hbase/HColumnDescriptor.java

@@ -428,6 +428,7 @@ public class HColumnDescriptor implements ColumnFamilyDescriptor, Comparable<HCo
    * will mask a later Put with lower ts. Set this to true to enable new semantics of versions.
    * We will also consider mvcc in versions. See HBASE-15968 for details.
    */
+  @Override
   public boolean isNewVersionBehavior() {
     return delegatee.isNewVersionBehavior();
   }

hbase-client/src/main/java/org/apache/hadoop/hbase/HRegionInfo.java

@@ -120,6 +120,7 @@ public class HRegionInfo implements RegionInfo, Comparable<HRegionInfo> {
   /**
    * @return Return a short, printable name for this region (usually encoded name) for us logging.
    */
+  @Override
   public String getShortNameToLog() {
     return prettyPrint(this.getEncodedName());
   }
@@ -189,7 +190,7 @@ public class HRegionInfo implements RegionInfo, Comparable<HRegionInfo> {
 
   private void setHashCode() {
     int result = Arrays.hashCode(this.regionName);
-    result ^= this.regionId;
+    result = (int) (result ^ this.regionId);
     result ^= Arrays.hashCode(this.startKey);
     result ^= Arrays.hashCode(this.endKey);
     result ^= Boolean.valueOf(this.offLine).hashCode();
@@ -473,6 +474,7 @@ public class HRegionInfo implements RegionInfo, Comparable<HRegionInfo> {
   }
 
   /** @return the regionId */
+  @Override
   public long getRegionId(){
     return regionId;
   }
@@ -481,6 +483,7 @@ public class HRegionInfo implements RegionInfo, Comparable<HRegionInfo> {
    * @return the regionName as an array of bytes.
    * @see #getRegionNameAsString()
    */
+  @Override
   public byte [] getRegionName(){
     return regionName;
   }
@@ -488,6 +491,7 @@ public class HRegionInfo implements RegionInfo, Comparable<HRegionInfo> {
   /**
    * @return Region name as a String for use in logging, etc.
    */
+  @Override
   public String getRegionNameAsString() {
     if (RegionInfo.hasEncodedName(this.regionName)) {
       // new format region names already have their encoded name.
@@ -500,7 +504,10 @@ public class HRegionInfo implements RegionInfo, Comparable<HRegionInfo> {
     return Bytes.toStringBinary(this.regionName) + "." + this.getEncodedName();
   }
 
-  /** @return the encoded region name */
+  /**
+   * @return the encoded region name
+   */
+  @Override
   public synchronized String getEncodedName() {
     if (this.encodedName == null) {
       this.encodedName = RegionInfo.encodeRegionName(this.regionName);
@@ -508,6 +515,7 @@ public class HRegionInfo implements RegionInfo, Comparable<HRegionInfo> {
     return this.encodedName;
   }
 
+  @Override
   public synchronized byte [] getEncodedNameAsBytes() {
     if (this.encodedNameAsBytes == null) {
       this.encodedNameAsBytes = Bytes.toBytes(getEncodedName());
@@ -515,12 +523,18 @@ public class HRegionInfo implements RegionInfo, Comparable<HRegionInfo> {
     return this.encodedNameAsBytes;
   }
 
-  /** @return the startKey */
+  /**
+   * @return the startKey
+   */
+  @Override
   public byte [] getStartKey(){
     return startKey;
   }
 
-  /** @return the endKey */
+  /**
+   * @return the endKey
+   */
+  @Override
   public byte [] getEndKey(){
     return endKey;
   }
@@ -529,6 +543,7 @@ public class HRegionInfo implements RegionInfo, Comparable<HRegionInfo> {
    * Get current table name of the region
    * @return TableName
    */
+  @Override
   public TableName getTable() {
     // This method name should be getTableName but there was already a method getTableName
     // that returned a byte array.  It is unfortunate given everywhere else, getTableName returns
@@ -546,6 +561,7 @@ public class HRegionInfo implements RegionInfo, Comparable<HRegionInfo> {
    * ["b","z"] it will return false.
    * @throws IllegalArgumentException if the range passed is invalid (ie. end &lt; start)
    */
+  @Override
   public boolean containsRange(byte[] rangeStartKey, byte[] rangeEndKey) {
     if (Bytes.compareTo(rangeStartKey, rangeEndKey) > 0) {
       throw new IllegalArgumentException(
@@ -561,8 +577,9 @@ public class HRegionInfo implements RegionInfo, Comparable<HRegionInfo> {
   }
 
   /**
-   * Return true if the given row falls in this region.
+   * @return true if the given row falls in this region.
    */
+  @Override
   public boolean containsRow(byte[] row) {
     return Bytes.compareTo(row, startKey) >= 0 &&
       (Bytes.compareTo(row, endKey) < 0 ||
@@ -576,7 +593,10 @@ public class HRegionInfo implements RegionInfo, Comparable<HRegionInfo> {
     return isMetaRegion();
   }
 
-  /** @return true if this region is a meta region */
+  /**
+   * @return true if this region is a meta region
+   */
+  @Override
   public boolean isMetaRegion() {
      return tableName.equals(HRegionInfo.FIRST_META_REGIONINFO.getTable());
   }
@@ -589,8 +609,9 @@ public class HRegionInfo implements RegionInfo, Comparable<HRegionInfo> {
   }
 
   /**
-   * @return True if has been split and has daughters.
+   * @return true if has been split and has daughters.
    */
+  @Override
   public boolean isSplit() {
     return this.split;
   }
@@ -603,8 +624,9 @@ public class HRegionInfo implements RegionInfo, Comparable<HRegionInfo> {
   }
 
   /**
-   * @return True if this region is offline.
+   * @return true if this region is offline.
    */
+  @Override
   public boolean isOffline() {
     return this.offLine;
   }
@@ -619,8 +641,9 @@ public class HRegionInfo implements RegionInfo, Comparable<HRegionInfo> {
   }
 
   /**
-   * @return True if this is a split parent region.
+   * @return true if this is a split parent region.
    */
+  @Override
   public boolean isSplitParent() {
     if (!isSplit()) return false;
     if (!isOffline()) {
@@ -633,6 +656,7 @@ public class HRegionInfo implements RegionInfo, Comparable<HRegionInfo> {
    * Returns the region replica id
    * @return returns region replica id
    */
+  @Override
   public int getReplicaId() {
     return replicaId;
   }

hbase-client/src/main/java/org/apache/hadoop/hbase/InvalidFamilyOperationException.java

@@ -26,7 +26,7 @@ import org.apache.yetus.audience.InterfaceAudience;
  */
 @InterfaceAudience.Public
 public class InvalidFamilyOperationException extends DoNotRetryIOException {
-  private static final long serialVersionUID = 1L << 22 - 1L;
+  private static final long serialVersionUID = (1L << 22) - 1L;
   /** default constructor */
   public InvalidFamilyOperationException() {
     super();

hbase-client/src/main/java/org/apache/hadoop/hbase/MasterNotRunningException.java

@@ -27,7 +27,7 @@ import org.apache.yetus.audience.InterfaceAudience;
  */
 @InterfaceAudience.Public
 public class MasterNotRunningException extends IOException {
-  private static final long serialVersionUID = 1L << 23 - 1L;
+  private static final long serialVersionUID = (1L << 23) - 1L;
   /** default constructor */
   public MasterNotRunningException() {
     super();

hbase-client/src/main/java/org/apache/hadoop/hbase/NotServingRegionException.java

@@ -29,7 +29,7 @@ import org.apache.hadoop.hbase.util.Bytes;
  */
 @InterfaceAudience.Public
 public class NotServingRegionException extends IOException {
-  private static final long serialVersionUID = 1L << 17 - 1L;
+  private static final long serialVersionUID = (1L << 17) - 1L;
 
   /** default constructor */
   public NotServingRegionException() {

hbase-client/src/main/java/org/apache/hadoop/hbase/RegionLocations.java

@@ -21,9 +21,9 @@ package org.apache.hadoop.hbase;
 import java.util.Collection;
 
 import org.apache.hadoop.hbase.client.RegionInfo;
-import org.apache.yetus.audience.InterfaceAudience;
 import org.apache.hadoop.hbase.client.RegionReplicaUtil;
 import org.apache.hadoop.hbase.util.Bytes;
+import org.apache.yetus.audience.InterfaceAudience;
 
 /**
  * Container for holding a list of {@link HRegionLocation}'s that correspond to the

hbase-client/src/main/java/org/apache/hadoop/hbase/TableExistsException.java

@@ -25,7 +25,7 @@ import org.apache.yetus.audience.InterfaceAudience;
  */
 @InterfaceAudience.Public
 public class TableExistsException extends DoNotRetryIOException {
-  private static final long serialVersionUID = 1L << 7 - 1L;
+  private static final long serialVersionUID = (1L << 7) - 1L;
   /** default constructor */
   public TableExistsException() {
     super();

hbase-client/src/main/java/org/apache/hadoop/hbase/TableNotDisabledException.java

@@ -26,7 +26,7 @@ import org.apache.hadoop.hbase.util.Bytes;
  */
 @InterfaceAudience.Public
 public class TableNotDisabledException extends DoNotRetryIOException {
-  private static final long serialVersionUID = 1L << 19 - 1L;
+  private static final long serialVersionUID = (1L << 19) - 1L;
   /** default constructor */
   public TableNotDisabledException() {
     super();

hbase-client/src/main/java/org/apache/hadoop/hbase/ZooKeeperConnectionException.java

@@ -27,7 +27,7 @@ import org.apache.yetus.audience.InterfaceAudience;
  */
 @InterfaceAudience.Public
 public class ZooKeeperConnectionException extends IOException {
-  private static final long serialVersionUID = 1L << 23 - 1L;
+  private static final long serialVersionUID = (1L << 23) - 1L;
   /** default constructor */
   public ZooKeeperConnectionException() {
     super();

hbase-client/src/main/java/org/apache/hadoop/hbase/client/Append.java

@@ -86,6 +86,7 @@ public class Append extends Mutation {
    *          A client that is not interested in the result can save network
    *          bandwidth setting this to false.
    */
+  @Override
   public Append setReturnResults(boolean returnResults) {
     super.setReturnResults(returnResults);
     return this;
@@ -95,6 +96,7 @@ public class Append extends Mutation {
    * @return current setting for returnResults
    */
   // This method makes public the superclasses's protected method.
+  @Override
   public boolean isReturnResults() {
     return super.isReturnResults();
   }

hbase-client/src/main/java/org/apache/hadoop/hbase/client/AsyncAdminRequestRetryingCaller.java

@@ -70,6 +70,7 @@ public class AsyncAdminRequestRetryingCaller<T> extends AsyncRpcRetryingCaller<T
     });
   }
 
+  @Override
   CompletableFuture<T> call() {
     doCall();
     return future;

hbase-client/src/main/java/org/apache/hadoop/hbase/client/AsyncMasterRequestRpcRetryingCaller.java

@@ -67,6 +67,7 @@ public class AsyncMasterRequestRpcRetryingCaller<T> extends AsyncRpcRetryingCall
     });
   }
 
+  @Override
   public CompletableFuture<T> call() {
     doCall();
     return future;

hbase-client/src/main/java/org/apache/hadoop/hbase/client/AsyncProcess.java

@@ -153,7 +153,7 @@ class AsyncProcess {
   final long pauseForCQTBE;// pause for CallQueueTooBigException, if specified
   final int numTries;
   @VisibleForTesting
-  int serverTrackerTimeout;
+  long serverTrackerTimeout;
   final long primaryCallTimeoutMicroseconds;
   /** Whether to log details for batch errors */
   final boolean logBatchErrorDetails;
@@ -204,9 +204,9 @@ class AsyncProcess {
     // If we keep hitting one server, the net effect will be the incremental backoff, and
     // essentially the same number of retries as planned. If we have to do faster retries,
     // we will do more retries in aggregate, but the user will be none the wiser.
-    this.serverTrackerTimeout = 0;
+    this.serverTrackerTimeout = 0L;
     for (int i = 0; i < this.numTries; ++i) {
-      serverTrackerTimeout += ConnectionUtils.getPauseTime(this.pause, i);
+      serverTrackerTimeout = serverTrackerTimeout + ConnectionUtils.getPauseTime(this.pause, i);
     }
 
     this.rpcCallerFactory = rpcCaller;

hbase-client/src/main/java/org/apache/hadoop/hbase/client/AsyncServerRequestRpcRetryingCaller.java

@@ -72,6 +72,7 @@ public class AsyncServerRequestRpcRetryingCaller<T> extends AsyncRpcRetryingCall
     });
   }
 
+  @Override
   CompletableFuture<T> call() {
     doCall();
     return future;

hbase-client/src/main/java/org/apache/hadoop/hbase/client/BufferedMutatorParams.java

@@ -151,6 +151,7 @@ public class BufferedMutatorParams implements Cloneable {
    */
   @edu.umd.cs.findbugs.annotations.SuppressWarnings(value="CN_IDIOM_NO_SUPER_CALL",
     justification="The clone below is complete")
+  @Override
   public BufferedMutatorParams clone() {
     BufferedMutatorParams clone = new BufferedMutatorParams(this.tableName);
     clone.writeBufferSize = this.writeBufferSize;

hbase-client/src/main/java/org/apache/hadoop/hbase/client/ColumnFamilyDescriptorBuilder.java

@@ -895,6 +895,7 @@ public class ColumnFamilyDescriptorBuilder {
      * will mask a later Put with lower ts. Set this to true to enable new semantics of versions.
      * We will also consider mvcc in versions. See HBASE-15968 for details.
      */
+    @Override
     public boolean isNewVersionBehavior() {
       return getStringOrDefault(NEW_VERSION_BEHAVIOR_BYTES,
           Boolean::parseBoolean, DEFAULT_NEW_VERSION_BEHAVIOR);

hbase-client/src/main/java/org/apache/hadoop/hbase/client/FastFailInterceptorContext.java

@@ -107,6 +107,7 @@ class FastFailInterceptorContext extends RetryingCallerInterceptorContext {
     this.tries = tries;
   }
 
+  @Override
   public void clear() {
     server = null;
     fInfo = null;
@@ -117,10 +118,12 @@ class FastFailInterceptorContext extends RetryingCallerInterceptorContext {
     tries = 0;
   }
 
+  @Override
   public FastFailInterceptorContext prepare(RetryingCallable<?> callable) {
     return prepare(callable, 0);
   }
 
+  @Override
   public FastFailInterceptorContext prepare(RetryingCallable<?> callable, int tries) {
     if (callable instanceof RegionServerCallable) {
       RegionServerCallable<?, ?> retryingCallable = (RegionServerCallable<?, ?>) callable;

hbase-client/src/main/java/org/apache/hadoop/hbase/client/Get.java

@@ -296,6 +296,7 @@ public class Get extends Query
     return this;
   }
 
+  @Override
   public Get setLoadColumnFamiliesOnDemand(boolean value) {
     return (Get) super.setLoadColumnFamiliesOnDemand(value);
   }

hbase-client/src/main/java/org/apache/hadoop/hbase/client/HBaseAdmin.java

@@ -1,5 +1,4 @@
 /*
- *
  * Licensed to the Apache Software Foundation (ASF) under one
  * or more contributor license agreements.  See the NOTICE file
  * distributed with this work for additional information
@@ -25,6 +24,7 @@ import com.google.protobuf.RpcController;
 import java.io.Closeable;
 import java.io.IOException;
 import java.io.InterruptedIOException;
+import java.nio.charset.StandardCharsets;
 import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.Collection;
@@ -313,7 +313,8 @@ public class HBaseAdmin implements Admin {
   }
 
   @Override
-  public List<TableDescriptor> listTableDescriptors(Pattern pattern, boolean includeSysTables) throws IOException {
+  public List<TableDescriptor> listTableDescriptors(Pattern pattern, boolean includeSysTables)
+      throws IOException {
     return executeCallable(new MasterCallable<List<TableDescriptor>>(getConnection(),
         getRpcControllerFactory()) {
       @Override
@@ -327,7 +328,8 @@ public class HBaseAdmin implements Admin {
   }
 
   @Override
-  public TableDescriptor getDescriptor(TableName tableName) throws TableNotFoundException, IOException {
+  public TableDescriptor getDescriptor(TableName tableName)
+      throws TableNotFoundException, IOException {
     return getTableDescriptor(tableName, getConnection(), rpcCallerFactory, rpcControllerFactory,
        operationTimeout, rpcTimeout);
   }
@@ -377,7 +379,8 @@ public class HBaseAdmin implements Admin {
       protected List<TableDescriptor> rpcCall() throws Exception {
         GetTableDescriptorsRequest req =
             RequestConverter.buildGetTableDescriptorsRequest(tableNames);
-          return ProtobufUtil.toTableDescriptorList(master.getTableDescriptors(getRpcController(), req));
+          return ProtobufUtil.toTableDescriptorList(master.getTableDescriptors(getRpcController(),
+              req));
       }
     });
   }
@@ -547,7 +550,9 @@ public class HBaseAdmin implements Admin {
   static HTableDescriptor getHTableDescriptor(final TableName tableName, Connection connection,
       RpcRetryingCallerFactory rpcCallerFactory, final RpcControllerFactory rpcControllerFactory,
       int operationTimeout, int rpcTimeout) throws IOException {
-    if (tableName == null) return null;
+    if (tableName == null) {
+      return null;
+    }
     HTableDescriptor htd =
         executeCallable(new MasterCallable<HTableDescriptor>(connection, rpcControllerFactory) {
           @Override
@@ -556,7 +561,8 @@ public class HBaseAdmin implements Admin {
                 RequestConverter.buildGetTableDescriptorsRequest(tableName);
             GetTableDescriptorsResponse htds = master.getTableDescriptors(getRpcController(), req);
             if (!htds.getTableSchemaList().isEmpty()) {
-          return new ImmutableHTableDescriptor(ProtobufUtil.toTableDescriptor(htds.getTableSchemaList().get(0)));
+              return new ImmutableHTableDescriptor(
+                  ProtobufUtil.toTableDescriptor(htds.getTableSchemaList().get(0)));
             }
             return null;
           }
@@ -1146,7 +1152,6 @@ public class HBaseAdmin implements Admin {
   }
 
   /**
-   *
    * @param sn
    * @return List of {@link HRegionInfo}.
    * @throws IOException
@@ -1573,9 +1578,8 @@ public class HBaseAdmin implements Admin {
   public boolean cleanerChoreSwitch(final boolean on) throws IOException {
     return executeCallable(new MasterCallable<Boolean>(getConnection(), getRpcControllerFactory()) {
       @Override public Boolean rpcCall() throws Exception {
-        return master.setCleanerChoreRunning(getRpcController(), RequestConverter
+        return master.setCleanerChoreRunning(getRpcController(),
-                                                                   .buildSetCleanerChoreRunningRequest(
+            RequestConverter.buildSetCleanerChoreRunningRequest(on)).getPrevValue();
-                                                                     on)).getPrevValue();
       }
     });
   }
@@ -1584,10 +1588,8 @@ public class HBaseAdmin implements Admin {
   public boolean runCleanerChore() throws IOException {
     return executeCallable(new MasterCallable<Boolean>(getConnection(), getRpcControllerFactory()) {
       @Override public Boolean rpcCall() throws Exception {
-        return master
+        return master.runCleanerChore(getRpcController(),
-                 .runCleanerChore(getRpcController(), RequestConverter
+            RequestConverter.buildRunCleanerChoreRequest()).getCleanerChoreRan();
-                                                        .buildRunCleanerChoreRequest())
-                 .getCleanerChoreRan();
       }
     });
   }
@@ -1597,8 +1599,7 @@ public class HBaseAdmin implements Admin {
     return executeCallable(new MasterCallable<Boolean>(getConnection(), getRpcControllerFactory()) {
       @Override public Boolean rpcCall() throws Exception {
         return master.isCleanerChoreEnabled(getRpcController(),
-                                            RequestConverter.buildIsCleanerChoreEnabledRequest())
+            RequestConverter.buildIsCleanerChoreEnabledRequest()).getValue();
-                     .getValue();
       }
     });
   }
@@ -1676,7 +1677,8 @@ public class HBaseAdmin implements Admin {
     byte[][] encodedNameofRegionsToMerge = new byte[nameofRegionsToMerge.length][];
     for(int i = 0; i < nameofRegionsToMerge.length; i++) {
       encodedNameofRegionsToMerge[i] = HRegionInfo.isEncodedRegionName(nameofRegionsToMerge[i]) ?
-        nameofRegionsToMerge[i] : HRegionInfo.encodeRegionName(nameofRegionsToMerge[i]).getBytes();
+        nameofRegionsToMerge[i] : HRegionInfo.encodeRegionName(nameofRegionsToMerge[i])
+          .getBytes(StandardCharsets.UTF_8);
     }
 
     TableName tableName = null;
@@ -1774,7 +1776,7 @@ public class HBaseAdmin implements Admin {
   public Future<Void> splitRegionAsync(byte[] regionName, byte[] splitPoint)
       throws IOException {
     byte[] encodedNameofRegionToSplit = HRegionInfo.isEncodedRegionName(regionName) ?
-        regionName : HRegionInfo.encodeRegionName(regionName).getBytes();
+        regionName : HRegionInfo.encodeRegionName(regionName).getBytes(StandardCharsets.UTF_8);
     Pair<RegionInfo, ServerName> pair = getRegion(regionName);
     if (pair != null) {
       if (pair.getFirst() != null &&
@@ -2355,10 +2357,9 @@ public class HBaseAdmin implements Admin {
       protected HTableDescriptor[] rpcCall() throws Exception {
         GetTableDescriptorsRequest req =
             RequestConverter.buildGetTableDescriptorsRequest(tableNames);
-          return ProtobufUtil.toTableDescriptorList(master.getTableDescriptors(getRpcController(), req))
+        return ProtobufUtil
-                  .stream()
+            .toTableDescriptorList(master.getTableDescriptors(getRpcController(), req)).stream()
-                  .map(ImmutableHTableDescriptor::new)
+            .map(ImmutableHTableDescriptor::new).toArray(HTableDescriptor[]::new);
-                  .toArray(HTableDescriptor[]::new);
       }
     });
   }
@@ -2746,8 +2747,8 @@ public class HBaseAdmin implements Admin {
   }
 
   @Override
-  public byte[] execProcedureWithReturn(String signature, String instance, Map<String, String> props)
+  public byte[] execProcedureWithReturn(String signature, String instance, Map<String,
-      throws IOException {
+      String> props) throws IOException {
     ProcedureDescription desc = ProtobufUtil.buildProcedureDescription(signature, instance, props);
     final ExecProcedureRequest request =
         ExecProcedureRequest.newBuilder().setProcedure(desc).build();
@@ -2833,7 +2834,8 @@ public class HBaseAdmin implements Admin {
   private Future<Void> internalRestoreSnapshotAsync(final String snapshotName,
       final TableName tableName, final boolean restoreAcl)
       throws IOException, RestoreSnapshotException {
-    final SnapshotProtos.SnapshotDescription snapshot = SnapshotProtos.SnapshotDescription.newBuilder()
+    final SnapshotProtos.SnapshotDescription snapshot =
+        SnapshotProtos.SnapshotDescription.newBuilder()
         .setName(snapshotName).setTable(tableName.getNameAsString()).build();
 
     // actually restore the snapshot
@@ -2977,9 +2979,8 @@ public class HBaseAdmin implements Admin {
       try {
         internalDeleteSnapshot(snapshot);
       } catch (IOException ex) {
-        LOG.info(
+        LOG.info("Failed to delete snapshot " + snapshot.getName() + " for table "
-          "Failed to delete snapshot " + snapshot.getName() + " for table " + snapshot.getTableNameAsString(),
+                + snapshot.getTableNameAsString(), ex);
-          ex);
       }
     }
   }
@@ -3991,7 +3992,8 @@ public class HBaseAdmin implements Admin {
               getRpcControllerFactory()) {
       @Override
       public List<ServerName> rpcCall() throws ServiceException {
-        ListDecommissionedRegionServersRequest req = ListDecommissionedRegionServersRequest.newBuilder().build();
+        ListDecommissionedRegionServersRequest req =
+            ListDecommissionedRegionServersRequest.newBuilder().build();
         List<ServerName> servers = new ArrayList<>();
         for (HBaseProtos.ServerName server : master
             .listDecommissionedRegionServers(getRpcController(), req).getServerNameList()) {

hbase-client/src/main/java/org/apache/hadoop/hbase/client/HTableMultiplexer.java

@@ -468,7 +468,7 @@ public class HTableMultiplexer {
     }
 
     public long getTotalBufferedCount() {
-      return queue.size() + currentProcessingCount.get();
+      return (long) queue.size() + currentProcessingCount.get();
     }
 
     public AtomicAverageCounter getAverageLatencyCounter() {

hbase-client/src/main/java/org/apache/hadoop/hbase/client/Increment.java

@@ -47,7 +47,7 @@ import org.apache.yetus.audience.InterfaceAudience;
  */
 @InterfaceAudience.Public
 public class Increment extends Mutation implements Comparable<Row> {
-  private static final long HEAP_OVERHEAD =  ClassSize.REFERENCE + ClassSize.TIMERANGE;
+  private static final int HEAP_OVERHEAD = ClassSize.REFERENCE + ClassSize.TIMERANGE;
   private TimeRange tr = new TimeRange();
 
   /**
@@ -164,6 +164,7 @@ public class Increment extends Mutation implements Comparable<Row> {
    *          client that is not interested in the result can save network bandwidth setting this
    *          to false.
    */
+  @Override
   public Increment setReturnResults(boolean returnResults) {
     super.setReturnResults(returnResults);
     return this;
@@ -173,6 +174,7 @@ public class Increment extends Mutation implements Comparable<Row> {
    * @return current setting for returnResults
    */
   // This method makes public the superclasses's protected method.
+  @Override
   public boolean isReturnResults() {
     return super.isReturnResults();
   }

hbase-client/src/main/java/org/apache/hadoop/hbase/client/NoServerForRegionException.java

@@ -25,7 +25,7 @@ import org.apache.yetus.audience.InterfaceAudience;
  */
 @InterfaceAudience.Public
 public class NoServerForRegionException extends DoNotRetryRegionException {
-  private static final long serialVersionUID = 1L << 11 - 1L;
+  private static final long serialVersionUID = (1L << 11) - 1L;
 
   /** default constructor */
   public NoServerForRegionException() {

hbase-client/src/main/java/org/apache/hadoop/hbase/client/PerClientRandomNonceGenerator.java

@@ -41,10 +41,12 @@ public final class PerClientRandomNonceGenerator implements NonceGenerator {
     this.clientId = (((long) Arrays.hashCode(clientIdBase)) << 32) + rdm.nextInt();
   }
 
+  @Override
   public long getNonceGroup() {
     return this.clientId;
   }
 
+  @Override
   public long newNonce() {
     long result = HConstants.NO_NONCE;
     do {

hbase-client/src/main/java/org/apache/hadoop/hbase/client/RegionInfoBuilder.java

@@ -168,7 +168,7 @@ public class RegionInfoBuilder {
         final byte[] endKey, final long regionId,
         final int replicaId, boolean offLine, byte[] regionName) {
       int result = Arrays.hashCode(regionName);
-      result ^= regionId;
+      result = (int) (result ^ regionId);
       result ^= Arrays.hashCode(checkStartKey(startKey));
       result ^= Arrays.hashCode(checkEndKey(endKey));
       result ^= Boolean.valueOf(offLine).hashCode();

hbase-client/src/main/java/org/apache/hadoop/hbase/client/RegionServerCallable.java

@@ -106,6 +106,7 @@ public abstract class RegionServerCallable<T, S> implements RetryingCallable<T>
    * Override that changes call Exception from {@link Exception} to {@link IOException}.
    * Also does set up of the rpcController.
    */
+  @Override
   public T call(int callTimeout) throws IOException {
     try {
       // Iff non-null and an instance of a SHADED rpcController, do config! Unshaded -- i.e.
@@ -183,6 +184,7 @@ public abstract class RegionServerCallable<T, S> implements RetryingCallable<T>
 
   protected int getPriority() { return this.priority;}
 
+  @Override
   public void throwable(Throwable t, boolean retrying) {
     if (location != null) {
       getConnection().updateCachedLocations(tableName, location.getRegionInfo().getRegionName(),
@@ -190,10 +192,12 @@ public abstract class RegionServerCallable<T, S> implements RetryingCallable<T>
     }
   }
 
+  @Override
   public String getExceptionMessageAdditionalDetail() {
     return "row '" + Bytes.toString(row) + "' on table '" + tableName + "' at " + location;
   }
 
+  @Override
   public long sleep(long pause, int tries) {
     return ConnectionUtils.getPauseTime(pause, tries);
   }
@@ -208,6 +212,7 @@ public abstract class RegionServerCallable<T, S> implements RetryingCallable<T>
     return this.location.getRegionInfo();
   }
 
+  @Override
   public void prepare(final boolean reload) throws IOException {
     // check table state if this is a retry
     if (reload && tableName != null && !tableName.equals(TableName.META_TABLE_NAME)

hbase-client/src/main/java/org/apache/hadoop/hbase/client/Scan.java

@@ -894,6 +894,7 @@ public class Scan extends Query {
     return allowPartialResults;
   }
 
+  @Override
   public Scan setLoadColumnFamiliesOnDemand(boolean value) {
     return (Scan) super.setLoadColumnFamiliesOnDemand(value);
   }

hbase-client/src/main/java/org/apache/hadoop/hbase/client/coprocessor/LongColumnInterpreter.java

@@ -43,6 +43,7 @@ import org.apache.hadoop.hbase.util.Bytes;
 public class LongColumnInterpreter extends ColumnInterpreter<Long, Long,
                  EmptyMsg, LongMsg, LongMsg> {
 
+  @Override
   public Long getValue(byte[] colFamily, byte[] colQualifier, Cell kv)
       throws IOException {
     if (kv == null || kv.getValueLength() != Bytes.SIZEOF_LONG)

hbase-client/src/main/java/org/apache/hadoop/hbase/client/security/SecurityCapability.java

@@ -32,7 +32,7 @@ public enum SecurityCapability {
   CELL_AUTHORIZATION(3),
   CELL_VISIBILITY(4);
 
-  private int value;
+  private final int value;
 
   public int getValue() {
     return value;

hbase-client/src/main/java/org/apache/hadoop/hbase/filter/BinaryComparator.java

@@ -58,6 +58,7 @@ public class BinaryComparator extends org.apache.hadoop.hbase.filter.ByteArrayCo
   /**
    * @return The comparator serialized using pb
    */
+  @Override
   public byte [] toByteArray() {
     ComparatorProtos.BinaryComparator.Builder builder =
       ComparatorProtos.BinaryComparator.newBuilder();
@@ -87,6 +88,7 @@ public class BinaryComparator extends org.apache.hadoop.hbase.filter.ByteArrayCo
    * @return true if and only if the fields of the comparator that are serialized
    * are equal to the corresponding fields in other.  Used for testing.
    */
+  @Override
   boolean areSerializedFieldsEqual(ByteArrayComparable other) {
     if (other == this) return true;
     if (!(other instanceof BinaryComparator)) return false;

hbase-client/src/main/java/org/apache/hadoop/hbase/filter/BinaryPrefixComparator.java

@@ -63,6 +63,7 @@ public class BinaryPrefixComparator extends ByteArrayComparable {
   /**
    * @return The comparator serialized using pb
    */
+  @Override
   public byte [] toByteArray() {
     ComparatorProtos.BinaryPrefixComparator.Builder builder =
       ComparatorProtos.BinaryPrefixComparator.newBuilder();
@@ -92,6 +93,7 @@ public class BinaryPrefixComparator extends ByteArrayComparable {
    * @return true if and only if the fields of the comparator that are serialized
    * are equal to the corresponding fields in other.  Used for testing.
    */
+  @Override
   boolean areSerializedFieldsEqual(ByteArrayComparable other) {
     if (other == this) return true;
     if (!(other instanceof BinaryPrefixComparator)) return false;

hbase-client/src/main/java/org/apache/hadoop/hbase/filter/BitComparator.java

@@ -67,6 +67,7 @@ public class BitComparator extends ByteArrayComparable {
   /**
    * @return The comparator serialized using pb
    */
+  @Override
   public byte [] toByteArray() {
     ComparatorProtos.BitComparator.Builder builder =
       ComparatorProtos.BitComparator.newBuilder();
@@ -100,6 +101,7 @@ public class BitComparator extends ByteArrayComparable {
    * @return true if and only if the fields of the comparator that are serialized
    * are equal to the corresponding fields in other.  Used for testing.
    */
+  @Override
   boolean areSerializedFieldsEqual(ByteArrayComparable other) {
     if (other == this) return true;
     if (!(other instanceof BitComparator)) return false;

hbase-client/src/main/java/org/apache/hadoop/hbase/filter/ColumnCountGetFilter.java

@@ -89,6 +89,7 @@ public class ColumnCountGetFilter extends FilterBase {
   /**
    * @return The filter serialized using pb
    */
+  @Override
   public byte [] toByteArray() {
     FilterProtos.ColumnCountGetFilter.Builder builder =
       FilterProtos.ColumnCountGetFilter.newBuilder();
@@ -118,6 +119,7 @@ public class ColumnCountGetFilter extends FilterBase {
    * @return true if and only if the fields of the filter that are serialized
    * are equal to the corresponding fields in other.  Used for testing.
    */
+  @Override
   boolean areSerializedFieldsEqual(Filter o) {
     if (o == this) return true;
     if (!(o instanceof ColumnCountGetFilter)) return false;

hbase-client/src/main/java/org/apache/hadoop/hbase/filter/ColumnPaginationFilter.java

@@ -168,6 +168,7 @@ public class ColumnPaginationFilter extends FilterBase {
   /**
    * @return The filter serialized using pb
    */
+  @Override
   public byte [] toByteArray() {
     FilterProtos.ColumnPaginationFilter.Builder builder =
       FilterProtos.ColumnPaginationFilter.newBuilder();
@@ -207,6 +208,7 @@ public class ColumnPaginationFilter extends FilterBase {
    * @return true if and only if the fields of the filter that are serialized
    * are equal to the corresponding fields in other.  Used for testing.
    */
+  @Override
   boolean areSerializedFieldsEqual(Filter o) {
     if (o == this) return true;
     if (!(o instanceof ColumnPaginationFilter)) return false;

hbase-client/src/main/java/org/apache/hadoop/hbase/filter/ColumnPrefixFilter.java

@@ -113,6 +113,7 @@ public class ColumnPrefixFilter extends FilterBase {
   /**
    * @return The filter serialized using pb
    */
+  @Override
   public byte [] toByteArray() {
     FilterProtos.ColumnPrefixFilter.Builder builder =
       FilterProtos.ColumnPrefixFilter.newBuilder();
@@ -142,6 +143,7 @@ public class ColumnPrefixFilter extends FilterBase {
    * @return true if and only if the fields of the filter that are serialized
    * are equal to the corresponding fields in other.  Used for testing.
    */
+  @Override
   boolean areSerializedFieldsEqual(Filter o) {
    if (o == this) return true;
    if (!(o instanceof ColumnPrefixFilter)) return false;

hbase-client/src/main/java/org/apache/hadoop/hbase/filter/ColumnRangeFilter.java

@@ -149,8 +149,7 @@ public class ColumnRangeFilter extends FilterBase {
 
     int cmpMax = CellUtil.compareQualifiers(c, this.maxColumn, 0, this.maxColumn.length);
 
-    if (this.maxColumnInclusive && cmpMax <= 0 ||
+    if ((this.maxColumnInclusive && cmpMax <= 0) || (!this.maxColumnInclusive && cmpMax < 0)) {
-        !this.maxColumnInclusive && cmpMax < 0) {
       return ReturnCode.INCLUDE;
     }
 
@@ -176,6 +175,7 @@ public class ColumnRangeFilter extends FilterBase {
   /**
    * @return The filter serialized using pb
    */
+  @Override
   public byte [] toByteArray() {
     FilterProtos.ColumnRangeFilter.Builder builder =
       FilterProtos.ColumnRangeFilter.newBuilder();
@@ -212,6 +212,7 @@ public class ColumnRangeFilter extends FilterBase {
    * @return true if and only if the fields of the filter that are serialized
    * are equal to the corresponding fields in other.  Used for testing.
    */
+  @Override
   boolean areSerializedFieldsEqual(Filter o) {
    if (o == this) return true;
    if (!(o instanceof ColumnRangeFilter)) return false;

hbase-client/src/main/java/org/apache/hadoop/hbase/filter/CompareFilter.java

@@ -300,6 +300,7 @@ public abstract class CompareFilter extends FilterBase {
    * @return true if and only if the fields of the filter that are serialized
    * are equal to the corresponding fields in other.  Used for testing.
    */
+  @Override
   boolean areSerializedFieldsEqual(Filter o) {
     if (o == this) return true;
     if (!(o instanceof CompareFilter)) return false;

hbase-client/src/main/java/org/apache/hadoop/hbase/filter/DependentColumnFilter.java

@@ -237,6 +237,7 @@ public class DependentColumnFilter extends CompareFilter {
   /**
    * @return The filter serialized using pb
    */
+  @Override
   public byte [] toByteArray() {
     FilterProtos.DependentColumnFilter.Builder builder =
       FilterProtos.DependentColumnFilter.newBuilder();
@@ -288,6 +289,7 @@ public class DependentColumnFilter extends CompareFilter {
    */
   @edu.umd.cs.findbugs.annotations.SuppressWarnings(
       value="RCN_REDUNDANT_NULLCHECK_OF_NONNULL_VALUE")
+  @Override
   boolean areSerializedFieldsEqual(Filter o) {
     if (o == this) return true;
     if (!(o instanceof DependentColumnFilter)) return false;

hbase-client/src/main/java/org/apache/hadoop/hbase/filter/FamilyFilter.java

@@ -99,6 +99,7 @@ public class FamilyFilter extends CompareFilter {
   /**
    * @return The filter serialized using pb
    */
+  @Override
   public byte [] toByteArray() {
     FilterProtos.FamilyFilter.Builder builder =
       FilterProtos.FamilyFilter.newBuilder();
@@ -137,6 +138,7 @@ public class FamilyFilter extends CompareFilter {
    * @return true if and only if the fields of the filter that are serialized
    * are equal to the corresponding fields in other.  Used for testing.
    */
+  @Override
   boolean areSerializedFieldsEqual(Filter o) {
     if (o == this) return true;
     if (!(o instanceof FamilyFilter)) return false;

hbase-client/src/main/java/org/apache/hadoop/hbase/filter/FilterBase.java

@@ -128,6 +128,7 @@ public abstract class FilterBase extends Filter {
    *
    * {@inheritDoc}
    */
+  @Override
   public Cell getNextCellHint(Cell currentCell) throws IOException {
     return null;
   }
@@ -138,6 +139,7 @@ public abstract class FilterBase extends Filter {
    *
    * {@inheritDoc}
    */
+  @Override
   public boolean isFamilyEssential(byte[] name) throws IOException {
     return true;
   }
@@ -155,6 +157,7 @@ public abstract class FilterBase extends Filter {
   /**
    * Return filter's info for debugging and logging purpose.
    */
+  @Override
   public String toString() {
     return this.getClass().getSimpleName();
   }
@@ -162,6 +165,7 @@ public abstract class FilterBase extends Filter {
   /**
    * Return length 0 byte array for Filters that don't require special serialization
    */
+  @Override
   public byte[] toByteArray() throws IOException {
     return new byte[0];
   }
@@ -173,6 +177,7 @@ public abstract class FilterBase extends Filter {
    * @return true if and only if the fields of the filter that are serialized
    * are equal to the corresponding fields in other.  Used for testing.
    */
+  @Override
   boolean areSerializedFieldsEqual(Filter other) {
     return true;
   }

hbase-client/src/main/java/org/apache/hadoop/hbase/filter/FilterList.java

@@ -198,6 +198,7 @@ final public class FilterList extends FilterBase {
   /**
    * @return The filter serialized using pb
    */
+  @Override
   public byte[] toByteArray() throws IOException {
     FilterProtos.FilterList.Builder builder = FilterProtos.FilterList.newBuilder();
     builder.setOperator(FilterProtos.FilterList.Operator.valueOf(operator.name()));
@@ -239,6 +240,7 @@ final public class FilterList extends FilterBase {
    * @return true if and only if the fields of the filter that are serialized are equal to the
    *         corresponding fields in other. Used for testing.
    */
+  @Override
   boolean areSerializedFieldsEqual(Filter other) {
     if (other == this) return true;
     if (!(other instanceof FilterList)) return false;

hbase-client/src/main/java/org/apache/hadoop/hbase/filter/FirstKeyOnlyFilter.java

@@ -41,6 +41,7 @@ public class FirstKeyOnlyFilter extends FilterBase {
   public FirstKeyOnlyFilter() {
   }
 
+  @Override
   public void reset() {
     foundKV = false;
   }
@@ -88,6 +89,7 @@ public class FirstKeyOnlyFilter extends FilterBase {
   /**
    * @return The filter serialized using pb
    */
+  @Override
   public byte [] toByteArray() {
     FilterProtos.FirstKeyOnlyFilter.Builder builder =
       FilterProtos.FirstKeyOnlyFilter.newBuilder();
@@ -117,6 +119,7 @@ public class FirstKeyOnlyFilter extends FilterBase {
    * @return true if and only if the fields of the filter that are serialized
    * are equal to the corresponding fields in other.  Used for testing.
    */
+  @Override
   boolean areSerializedFieldsEqual(Filter o) {
     if (o == this) return true;
     if (!(o instanceof FirstKeyOnlyFilter)) return false;

hbase-client/src/main/java/org/apache/hadoop/hbase/filter/FirstKeyValueMatchingQualifiersFilter.java

@@ -88,6 +88,7 @@ public class FirstKeyValueMatchingQualifiersFilter extends FirstKeyOnlyFilter {
   /**
    * @return The filter serialized using pb
    */
+  @Override
   public byte [] toByteArray() {
     FilterProtos.FirstKeyValueMatchingQualifiersFilter.Builder builder =
       FilterProtos.FirstKeyValueMatchingQualifiersFilter.newBuilder();
@@ -124,6 +125,7 @@ public class FirstKeyValueMatchingQualifiersFilter extends FirstKeyOnlyFilter {
    * @return true if and only if the fields of the filter that are serialized
    * are equal to the corresponding fields in other.  Used for testing.
    */
+  @Override
   boolean areSerializedFieldsEqual(Filter o) {
     if (o == this) return true;
     if (!(o instanceof FirstKeyValueMatchingQualifiersFilter)) return false;

hbase-client/src/main/java/org/apache/hadoop/hbase/filter/FuzzyRowFilter.java

@@ -263,6 +263,7 @@ public class FuzzyRowFilter extends FilterBase {
   /**
    * @return The filter serialized using pb
    */
+  @Override
   public byte[] toByteArray() {
     FilterProtos.FuzzyRowFilter.Builder builder = FilterProtos.FuzzyRowFilter.newBuilder();
     for (Pair<byte[], byte[]> fuzzyData : fuzzyKeysData) {
@@ -457,45 +458,55 @@ public class FuzzyRowFilter extends FilterBase {
   /** Abstracts directional comparisons based on scan direction. */
   private enum Order {
     ASC {
+      @Override
       public boolean lt(int lhs, int rhs) {
         return lhs < rhs;
       }
 
+      @Override
       public boolean gt(int lhs, int rhs) {
         return lhs > rhs;
       }
 
+      @Override
       public byte inc(byte val) {
         // TODO: what about over/underflow?
         return (byte) (val + 1);
       }
 
+      @Override
       public boolean isMax(byte val) {
         return val == (byte) 0xff;
       }
 
+      @Override
       public byte min() {
         return 0;
       }
     },
     DESC {
+      @Override
       public boolean lt(int lhs, int rhs) {
         return lhs > rhs;
       }
 
+      @Override
       public boolean gt(int lhs, int rhs) {
         return lhs < rhs;
       }
 
+      @Override
       public byte inc(byte val) {
         // TODO: what about over/underflow?
         return (byte) (val - 1);
       }
 
+      @Override
       public boolean isMax(byte val) {
         return val == 0;
       }
 
+      @Override
       public byte min() {
         return (byte) 0xFF;
       }
@@ -618,6 +629,7 @@ public class FuzzyRowFilter extends FilterBase {
    * @return true if and only if the fields of the filter that are serialized are equal to the
    *         corresponding fields in other. Used for testing.
    */
+  @Override
   boolean areSerializedFieldsEqual(Filter o) {
     if (o == this) return true;
     if (!(o instanceof FuzzyRowFilter)) return false;

hbase-client/src/main/java/org/apache/hadoop/hbase/filter/InclusiveStopFilter.java

@@ -63,6 +63,7 @@ public class InclusiveStopFilter extends FilterBase {
     return ReturnCode.INCLUDE;
   }
 
+  @Override
   public boolean filterRowKey(Cell firstRowCell) {
     // if stopRowKey is <= buffer, then true, filter row.
     if (filterAllRemaining()) return true;
@@ -71,6 +72,7 @@ public class InclusiveStopFilter extends FilterBase {
     return done;
   }
 
+  @Override
   public boolean filterAllRemaining() {
     return done;
   }
@@ -85,6 +87,7 @@ public class InclusiveStopFilter extends FilterBase {
   /**
    * @return The filter serialized using pb
    */
+  @Override
   public byte [] toByteArray() {
     FilterProtos.InclusiveStopFilter.Builder builder =
       FilterProtos.InclusiveStopFilter.newBuilder();
@@ -115,6 +118,7 @@ public class InclusiveStopFilter extends FilterBase {
    * @return true if and only if the fields of the filter that are serialized
    * are equal to the corresponding fields in other.  Used for testing.
    */
+  @Override
   boolean areSerializedFieldsEqual(Filter o) {
     if (o == this) return true;
     if (!(o instanceof InclusiveStopFilter)) return false;

hbase-client/src/main/java/org/apache/hadoop/hbase/filter/KeyOnlyFilter.java

@@ -91,6 +91,7 @@ public class KeyOnlyFilter extends FilterBase {
   /**
    * @return The filter serialized using pb
    */
+  @Override
   public byte [] toByteArray() {
     FilterProtos.KeyOnlyFilter.Builder builder =
       FilterProtos.KeyOnlyFilter.newBuilder();
@@ -120,6 +121,7 @@ public class KeyOnlyFilter extends FilterBase {
    * @return true if and only if the fields of the filter that are serialized
    * are equal to the corresponding fields in other.  Used for testing.
    */
+  @Override
   boolean areSerializedFieldsEqual(Filter o) {
     if (o == this) return true;
     if (!(o instanceof KeyOnlyFilter)) return false;

hbase-client/src/main/java/org/apache/hadoop/hbase/filter/MultiRowRangeFilter.java

@@ -146,6 +146,7 @@ public class MultiRowRangeFilter extends FilterBase {
   /**
    * @return The filter serialized using pb
    */
+  @Override
   public byte[] toByteArray() {
     FilterProtos.MultiRowRangeFilter.Builder builder = FilterProtos.MultiRowRangeFilter
         .newBuilder();
@@ -194,6 +195,7 @@ public class MultiRowRangeFilter extends FilterBase {
    * @return true if and only if the fields of the filter that are serialized are equal to the
    *         corresponding fields in other. Used for testing.
    */
+  @Override
   boolean areSerializedFieldsEqual(Filter o) {
     if (o == this)
       return true;

hbase-client/src/main/java/org/apache/hadoop/hbase/filter/MultipleColumnPrefixFilter.java

@@ -118,6 +118,7 @@ public class MultipleColumnPrefixFilter extends FilterBase {
   /**
    * @return The filter serialized using pb
    */
+  @Override
   public byte [] toByteArray() {
     FilterProtos.MultipleColumnPrefixFilter.Builder builder =
       FilterProtos.MultipleColumnPrefixFilter.newBuilder();
@@ -155,6 +156,7 @@ public class MultipleColumnPrefixFilter extends FilterBase {
    * @return true if and only if the fields of the filter that are serialized
    * are equal to the corresponding fields in other.  Used for testing.
    */
+  @Override
   boolean areSerializedFieldsEqual(Filter o) {
     if (o == this) return true;
     if (!(o instanceof MultipleColumnPrefixFilter)) return false;

hbase-client/src/main/java/org/apache/hadoop/hbase/filter/NullComparator.java

@@ -67,6 +67,7 @@ public class NullComparator extends ByteArrayComparable {
   /**
    * @return The comparator serialized using pb
    */
+  @Override
   public byte [] toByteArray() {
     ComparatorProtos.NullComparator.Builder builder =
       ComparatorProtos.NullComparator.newBuilder();
@@ -95,6 +96,7 @@ public class NullComparator extends ByteArrayComparable {
    * @return true if and only if the fields of the comparator that are serialized
    * are equal to the corresponding fields in other.  Used for testing.
    */
+  @Override
   boolean areSerializedFieldsEqual(ByteArrayComparable other) {
     if (other == this) return true;
     if (!(other instanceof NullComparator)) return false;

hbase-client/src/main/java/org/apache/hadoop/hbase/filter/PageFilter.java

@@ -22,12 +22,13 @@ import java.io.IOException;
 import java.util.ArrayList;
 
 import org.apache.hadoop.hbase.Cell;
-import org.apache.yetus.audience.InterfaceAudience;
 import org.apache.hadoop.hbase.exceptions.DeserializationException;
-import org.apache.hadoop.hbase.shaded.protobuf.generated.FilterProtos;
+import org.apache.yetus.audience.InterfaceAudience;
 
 import org.apache.hadoop.hbase.shaded.com.google.common.base.Preconditions;
 import org.apache.hadoop.hbase.shaded.com.google.protobuf.InvalidProtocolBufferException;
+import org.apache.hadoop.hbase.shaded.protobuf.generated.FilterProtos;
+
 /**
  * Implementation of Filter interface that limits results to a specific page
  * size. It terminates scanning once the number of filter-passed rows is >
@@ -76,15 +77,18 @@ public class PageFilter extends FilterBase {
     return ReturnCode.INCLUDE;
   }
 
+  @Override
   public boolean filterAllRemaining() {
     return this.rowsAccepted >= this.pageSize;
   }
 
+  @Override
   public boolean filterRow() {
     this.rowsAccepted++;
     return this.rowsAccepted > this.pageSize;
   }
   
+  @Override
   public boolean hasFilterRow() {
     return true;
   }
@@ -99,6 +103,7 @@ public class PageFilter extends FilterBase {
   /**
    * @return The filter serialized using pb
    */
+  @Override
   public byte [] toByteArray() {
     FilterProtos.PageFilter.Builder builder =
       FilterProtos.PageFilter.newBuilder();
@@ -124,13 +129,18 @@ public class PageFilter extends FilterBase {
   }
 
   /**
-   * @param other
+   * @param o other Filter to compare with
-   * @return true if and only if the fields of the filter that are serialized
+   * @return true if and only if the fields of the filter that are serialized are equal to the
-   * are equal to the corresponding fields in other.  Used for testing.
+   *         corresponding fields in other.  Used for testing.
    */
+  @Override
   boolean areSerializedFieldsEqual(Filter o) {
-    if (o == this) return true;
+    if (o == this) {
-    if (!(o instanceof PageFilter)) return false;
+      return true;
+    }
+    if (!(o instanceof PageFilter)) {
+      return false;
+    }
 
     PageFilter other = (PageFilter)o;
     return this.getPageSize() == other.getPageSize();

hbase-client/src/main/java/org/apache/hadoop/hbase/filter/ParseFilter.java

@@ -22,6 +22,7 @@ import java.lang.reflect.InvocationTargetException;
 import java.lang.reflect.Method;
 import java.nio.ByteBuffer;
 import java.nio.charset.CharacterCodingException;
+import java.nio.charset.StandardCharsets;
 import java.util.ArrayList;
 import java.util.Collections;
 import java.util.EmptyStackException;
@@ -261,7 +262,7 @@ public class ParseFilter {
       e.printStackTrace();
     }
     throw new IllegalArgumentException("Incorrect filter string " +
-                                       new String(filterStringAsByteArray));
+        new String(filterStringAsByteArray, StandardCharsets.UTF_8));
   }
 
 /**
@@ -837,9 +838,9 @@ public class ParseFilter {
     else if (Bytes.equals(comparatorType, ParseConstants.binaryPrefixType))
       return new BinaryPrefixComparator(comparatorValue);
     else if (Bytes.equals(comparatorType, ParseConstants.regexStringType))
-      return new RegexStringComparator(new String(comparatorValue));
+      return new RegexStringComparator(new String(comparatorValue, StandardCharsets.UTF_8));
     else if (Bytes.equals(comparatorType, ParseConstants.substringType))
-      return new SubstringComparator(new String(comparatorValue));
+      return new SubstringComparator(new String(comparatorValue, StandardCharsets.UTF_8));
     else
       throw new IllegalArgumentException("Incorrect comparatorType");
   }

hbase-client/src/main/java/org/apache/hadoop/hbase/filter/PrefixFilter.java

@@ -50,6 +50,7 @@ public class PrefixFilter extends FilterBase {
     return prefix;
   }
 
+  @Override
   public boolean filterRowKey(Cell firstRowCell) {
     if (firstRowCell == null || this.prefix == null)
       return true;
@@ -87,14 +88,17 @@ public class PrefixFilter extends FilterBase {
     return ReturnCode.INCLUDE;
   }
 
+  @Override
   public boolean filterRow() {
     return filterRow;
   }
 
+  @Override
   public void reset() {
     filterRow = true;
   }
 
+  @Override
   public boolean filterAllRemaining() {
     return passedPrefix;
   }
@@ -109,6 +113,7 @@ public class PrefixFilter extends FilterBase {
   /**
    * @return The filter serialized using pb
    */
+  @Override
   public byte [] toByteArray() {
     FilterProtos.PrefixFilter.Builder builder =
       FilterProtos.PrefixFilter.newBuilder();
@@ -138,6 +143,7 @@ public class PrefixFilter extends FilterBase {
    * @return true if and only if the fields of the filter that are serialized
    * are equal to the corresponding fields in other.  Used for testing.
    */
+  @Override
   boolean areSerializedFieldsEqual(Filter o) {
     if (o == this) return true;
     if (!(o instanceof PrefixFilter)) return false;

hbase-client/src/main/java/org/apache/hadoop/hbase/filter/QualifierFilter.java

@@ -97,6 +97,7 @@ public class QualifierFilter extends CompareFilter {
   /**
    * @return The filter serialized using pb
    */
+  @Override
   public byte [] toByteArray() {
     FilterProtos.QualifierFilter.Builder builder =
       FilterProtos.QualifierFilter.newBuilder();
@@ -135,6 +136,7 @@ public class QualifierFilter extends CompareFilter {
    * @return true if and only if the fields of the filter that are serialized
    * are equal to the corresponding fields in other.  Used for testing.
    */
+  @Override
   boolean areSerializedFieldsEqual(Filter o) {
     if (o == this) return true;
     if (!(o instanceof QualifierFilter)) return false;

hbase-client/src/main/java/org/apache/hadoop/hbase/filter/RandomRowFilter.java

@@ -88,6 +88,7 @@ public class RandomRowFilter extends FilterBase {
     return filterOutRow;
   }
 
+  @Override
   public boolean hasFilterRow() {
     return true;
   }
@@ -115,6 +116,7 @@ public class RandomRowFilter extends FilterBase {
   /**
    * @return The filter serialized using pb
    */
+  @Override
   public byte [] toByteArray() {
     FilterProtos.RandomRowFilter.Builder builder =
       FilterProtos.RandomRowFilter.newBuilder();
@@ -144,6 +146,7 @@ public class RandomRowFilter extends FilterBase {
    * @return true if and only if the fields of the filter that are serialized
    * are equal to the corresponding fields in other.  Used for testing.
    */
+  @Override
   boolean areSerializedFieldsEqual(Filter o) {
     if (o == this) return true;
     if (!(o instanceof RandomRowFilter)) return false;

hbase-client/src/main/java/org/apache/hadoop/hbase/filter/RowFilter.java

@@ -114,6 +114,7 @@ public class RowFilter extends CompareFilter {
  /**
   * @return The filter serialized using pb
   */
+  @Override
   public byte [] toByteArray() {
     FilterProtos.RowFilter.Builder builder =
       FilterProtos.RowFilter.newBuilder();
@@ -152,6 +153,7 @@ public class RowFilter extends CompareFilter {
    * @return true if and only if the fields of the filter that are serialized
    * are equal to the corresponding fields in other.  Used for testing.
    */
+  @Override
   boolean areSerializedFieldsEqual(Filter o) {
     if (o == this) return true;
     if (!(o instanceof RowFilter)) return false;

hbase-client/src/main/java/org/apache/hadoop/hbase/filter/SingleColumnValueExcludeFilter.java

@@ -156,6 +156,7 @@ public class SingleColumnValueExcludeFilter extends SingleColumnValueFilter {
   }
 
   // We cleaned result row in FilterRow to be consistent with scanning process.
+  @Override
   public boolean hasFilterRow() {
    return true;
   }
@@ -190,6 +191,7 @@ public class SingleColumnValueExcludeFilter extends SingleColumnValueFilter {
   /**
    * @return The filter serialized using pb
    */
+  @Override
   public byte [] toByteArray() {
     FilterProtos.SingleColumnValueExcludeFilter.Builder builder =
       FilterProtos.SingleColumnValueExcludeFilter.newBuilder();
@@ -232,6 +234,7 @@ public class SingleColumnValueExcludeFilter extends SingleColumnValueFilter {
    * @return true if and only if the fields of the filter that are serialized
    * are equal to the corresponding fields in other.  Used for testing.
    */
+  @Override
   boolean areSerializedFieldsEqual(Filter o) {
     if (o == this) return true;
     if (!(o instanceof SingleColumnValueExcludeFilter)) return false;

hbase-client/src/main/java/org/apache/hadoop/hbase/filter/SingleColumnValueFilter.java

@@ -278,16 +278,19 @@ public class SingleColumnValueFilter extends FilterBase {
     return CompareFilter.compare(this.op, compareResult);
   }
 
+  @Override
   public boolean filterRow() {
     // If column was found, return false if it was matched, true if it was not
     // If column not found, return true if we filter if missing, false if not
     return this.foundColumn? !this.matchedColumn: this.filterIfMissing;
   }
   
+  @Override
   public boolean hasFilterRow() {
     return true;
   }
 
+  @Override
   public void reset() {
     foundColumn = false;
     matchedColumn = false;
@@ -387,6 +390,7 @@ public class SingleColumnValueFilter extends FilterBase {
   /**
    * @return The filter serialized using pb
    */
+  @Override
   public byte [] toByteArray() {
     return convert().toByteArray();
   }
@@ -425,6 +429,7 @@ public class SingleColumnValueFilter extends FilterBase {
    * @return true if and only if the fields of the filter that are serialized
    * are equal to the corresponding fields in other.  Used for testing.
    */
+  @Override
   boolean areSerializedFieldsEqual(Filter o) {
     if (o == this) return true;
     if (!(o instanceof SingleColumnValueFilter)) return false;
@@ -443,6 +448,7 @@ public class SingleColumnValueFilter extends FilterBase {
    * column in whole scan. If filterIfMissing == false, all families are essential,
    * because of possibility of skipping the rows without any data in filtered CF.
    */
+  @Override
   public boolean isFamilyEssential(byte[] name) {
     return !this.filterIfMissing || Bytes.equals(name, this.columnFamily);
   }

hbase-client/src/main/java/org/apache/hadoop/hbase/filter/SkipFilter.java

@@ -96,10 +96,12 @@ public class SkipFilter extends FilterBase {
     return filter.transformCell(v);
   }
 
+  @Override
   public boolean filterRow() {
     return filterRow;
   }
     
+  @Override
   public boolean hasFilterRow() {
     return true;
   }
@@ -107,6 +109,7 @@ public class SkipFilter extends FilterBase {
   /**
    * @return The filter serialized using pb
    */
+  @Override
   public byte[] toByteArray() throws IOException {
     FilterProtos.SkipFilter.Builder builder =
       FilterProtos.SkipFilter.newBuilder();
@@ -140,6 +143,7 @@ public class SkipFilter extends FilterBase {
    * @return true if and only if the fields of the filter that are serialized
    * are equal to the corresponding fields in other.  Used for testing.
    */
+  @Override
   boolean areSerializedFieldsEqual(Filter o) {
     if (o == this) return true;
     if (!(o instanceof SkipFilter)) return false;
@@ -148,6 +152,7 @@ public class SkipFilter extends FilterBase {
     return getFilter().areSerializedFieldsEqual(other.getFilter());
   }
 
+  @Override
   public boolean isFamilyEssential(byte[] name) throws IOException {
     return filter.isFamilyEssential(name);
   }

hbase-client/src/main/java/org/apache/hadoop/hbase/filter/SubstringComparator.java

@@ -70,6 +70,7 @@ public class SubstringComparator extends ByteArrayComparable {
   /**
    * @return The comparator serialized using pb
    */
+  @Override
   public byte [] toByteArray() {
     ComparatorProtos.SubstringComparator.Builder builder =
       ComparatorProtos.SubstringComparator.newBuilder();
@@ -99,6 +100,7 @@ public class SubstringComparator extends ByteArrayComparable {
    * @return true if and only if the fields of the comparator that are serialized
    * are equal to the corresponding fields in other.  Used for testing.
    */
+  @Override
   boolean areSerializedFieldsEqual(ByteArrayComparable other) {
     if (other == this) return true;
     if (!(other instanceof SubstringComparator)) return false;

hbase-client/src/main/java/org/apache/hadoop/hbase/filter/TimestampsFilter.java

@@ -135,6 +135,7 @@ public class TimestampsFilter extends FilterBase {
    *
    * @throws IOException This will never happen.
    */
+  @Override
   public Cell getNextCellHint(Cell currentCell) throws IOException {
     if (!canHint) {
       return null;
@@ -172,6 +173,7 @@ public class TimestampsFilter extends FilterBase {
   /**
    * @return The filter serialized using pb
    */
+  @Override
   public byte[] toByteArray() {
     FilterProtos.TimestampsFilter.Builder builder =
         FilterProtos.TimestampsFilter.newBuilder();
@@ -203,6 +205,7 @@ public class TimestampsFilter extends FilterBase {
    * @return true if and only if the fields of the filter that are serialized
    * are equal to the corresponding fields in other.  Used for testing.
    */
+  @Override
   boolean areSerializedFieldsEqual(Filter o) {
     if (o == this) return true;
     if (!(o instanceof TimestampsFilter)) return false;

hbase-client/src/main/java/org/apache/hadoop/hbase/filter/ValueFilter.java

@@ -93,6 +93,7 @@ public class ValueFilter extends CompareFilter {
   /**
    * @return The filter serialized using pb
    */
+  @Override
   public byte [] toByteArray() {
     FilterProtos.ValueFilter.Builder builder =
       FilterProtos.ValueFilter.newBuilder();
@@ -128,10 +129,10 @@ public class ValueFilter extends CompareFilter {
   }
 
   /**
-
    * @return true if and only if the fields of the filter that are serialized
    * are equal to the corresponding fields in other.  Used for testing.
    */
+  @Override
   boolean areSerializedFieldsEqual(Filter o) {
     if (o == this) return true;
     if (!(o instanceof ValueFilter)) return false;

hbase-client/src/main/java/org/apache/hadoop/hbase/filter/WhileMatchFilter.java

@@ -49,6 +49,7 @@ public class WhileMatchFilter extends FilterBase {
     return filter;
   }
 
+  @Override
   public void reset() throws IOException {
     this.filter.reset();
   }
@@ -110,6 +111,7 @@ public class WhileMatchFilter extends FilterBase {
   /**
    * @return The filter serialized using pb
    */
+  @Override
   public byte[] toByteArray() throws IOException {
     FilterProtos.WhileMatchFilter.Builder builder =
       FilterProtos.WhileMatchFilter.newBuilder();
@@ -143,6 +145,7 @@ public class WhileMatchFilter extends FilterBase {
    * @return true if and only if the fields of the filter that are serialized
    * are equal to the corresponding fields in other.  Used for testing.
    */
+  @Override
   boolean areSerializedFieldsEqual(Filter o) {
     if (o == this) return true;
     if (!(o instanceof WhileMatchFilter)) return false;
@@ -151,6 +154,7 @@ public class WhileMatchFilter extends FilterBase {
     return getFilter().areSerializedFieldsEqual(other.getFilter());
   }
 
+  @Override
   public boolean isFamilyEssential(byte[] name) throws IOException {
     return filter.isFamilyEssential(name);
   }

hbase-client/src/main/java/org/apache/hadoop/hbase/ipc/AbstractRpcClient.java

@@ -243,7 +243,7 @@ public abstract class AbstractRpcClient<T extends RpcConnection> implements RpcC
       return null;
     }
     try {
-      return (Codec) Class.forName(className).newInstance();
+      return (Codec) Class.forName(className).getDeclaredConstructor().newInstance();
     } catch (Exception e) {
       throw new RuntimeException("Failed getting codec " + className, e);
     }
@@ -271,7 +271,7 @@ public abstract class AbstractRpcClient<T extends RpcConnection> implements RpcC
       return null;
     }
     try {
-      return (CompressionCodec) Class.forName(className).newInstance();
+      return (CompressionCodec) Class.forName(className).getDeclaredConstructor().newInstance();
     } catch (Exception e) {
       throw new RuntimeException("Failed getting compressor " + className, e);
     }

hbase-client/src/main/java/org/apache/hadoop/hbase/ipc/BlockingRpcClient.java

@@ -67,6 +67,7 @@ public class BlockingRpcClient extends AbstractRpcClient<BlockingRpcConnection>
    * Creates a connection. Can be overridden by a subclass for testing.
    * @param remoteId - the ConnectionId to use for the connection creation.
    */
+  @Override
   protected BlockingRpcConnection createConnection(ConnectionId remoteId) throws IOException {
     return new BlockingRpcConnection(this, remoteId);
   }

hbase-client/src/main/java/org/apache/hadoop/hbase/ipc/ConnectionId.java

@@ -1,4 +1,4 @@
-/**
+/*
  * Licensed to the Apache Software Foundation (ASF) under one
  * or more contributor license agreements.  See the NOTICE file
  * distributed with this work for additional information
@@ -18,9 +18,10 @@
 package org.apache.hadoop.hbase.ipc;
 
 import java.net.InetSocketAddress;
+import java.util.Objects;
 
-import org.apache.yetus.audience.InterfaceAudience;
 import org.apache.hadoop.hbase.security.User;
+import org.apache.yetus.audience.InterfaceAudience;
 
 /**
  * This class holds the address and the user ticket, etc. The client connections
@@ -62,8 +63,7 @@ class ConnectionId {
       ConnectionId id = (ConnectionId) obj;
       return address.equals(id.address) &&
             ((ticket != null && ticket.equals(id.ticket)) ||
-             (ticket == id.ticket)) &&
+             (ticket == id.ticket)) && Objects.equals(this.serviceName, id.serviceName);
-             this.serviceName == id.serviceName;
     }
     return false;
   }
@@ -73,7 +73,7 @@ class ConnectionId {
     return hashCode(ticket,serviceName,address);
   }
 
-  public static int hashCode(User ticket, String serviceName, InetSocketAddress address){
+  public static int hashCode(User ticket, String serviceName, InetSocketAddress address) {
     return (address.hashCode() +
         PRIME * (PRIME * serviceName.hashCode() ^
             (ticket == null ? 0 : ticket.hashCode())));

hbase-client/src/main/java/org/apache/hadoop/hbase/quotas/QuotaRetriever.java

@@ -85,6 +85,7 @@ public class QuotaRetriever implements Closeable, Iterable<QuotaSettings> {
     }
   }
 
+  @Override
   public void close() throws IOException {
     if (this.table != null) {
       this.table.close();

hbase-client/src/main/java/org/apache/hadoop/hbase/regionserver/RegionServerRunningException.java

@@ -28,7 +28,7 @@ import org.apache.yetus.audience.InterfaceAudience;
  */
 @InterfaceAudience.Public
 public class RegionServerRunningException extends IOException {
-  private static final long serialVersionUID = 1L << 31 - 1L;
+  private static final long serialVersionUID = (1L << 31) - 1L;
 
   /** Default Constructor */
   public RegionServerRunningException() {

hbase-client/src/main/java/org/apache/hadoop/hbase/security/SaslUtil.java

@@ -18,6 +18,7 @@
  */
 package org.apache.hadoop.hbase.security;
 
+import java.nio.charset.StandardCharsets;
 import java.util.Map;
 import java.util.TreeMap;
 
@@ -68,15 +69,15 @@ public class SaslUtil {
   }
 
   static String encodeIdentifier(byte[] identifier) {
-    return new String(Base64.encodeBase64(identifier));
+    return new String(Base64.encodeBase64(identifier), StandardCharsets.UTF_8);
   }
 
   static byte[] decodeIdentifier(String identifier) {
-    return Base64.decodeBase64(identifier.getBytes());
+    return Base64.decodeBase64(identifier.getBytes(StandardCharsets.UTF_8));
   }
 
   static char[] encodePassword(byte[] password) {
-    return new String(Base64.encodeBase64(password)).toCharArray();
+    return new String(Base64.encodeBase64(password), StandardCharsets.UTF_8).toCharArray();
   }
 
   /**

hbase-client/src/main/java/org/apache/hadoop/hbase/security/access/Permission.java

@@ -46,7 +46,7 @@ public class Permission extends VersionedWritable {
   public enum Action {
     READ('R'), WRITE('W'), EXEC('X'), CREATE('C'), ADMIN('A');
 
-    private byte code;
+    private final byte code;
     Action(char code) {
       this.code = (byte)code;
     }

hbase-client/src/main/java/org/apache/hadoop/hbase/security/visibility/VisibilityClient.java

@@ -19,13 +19,15 @@ package org.apache.hadoop.hbase.security.visibility;
 
 import static org.apache.hadoop.hbase.security.visibility.VisibilityConstants.LABELS_TABLE_NAME;
 
+import com.google.protobuf.ByteString;
+import com.google.protobuf.ServiceException;
+
 import java.io.IOException;
 import java.util.Map;
 import java.util.regex.Pattern;
 
 import org.apache.hadoop.conf.Configuration;
 import org.apache.hadoop.hbase.HConstants;
-import org.apache.yetus.audience.InterfaceAudience;
 import org.apache.hadoop.hbase.client.Connection;
 import org.apache.hadoop.hbase.client.ConnectionFactory;
 import org.apache.hadoop.hbase.client.Table;
@@ -44,9 +46,8 @@ import org.apache.hadoop.hbase.protobuf.generated.VisibilityLabelsProtos.Visibil
 import org.apache.hadoop.hbase.protobuf.generated.VisibilityLabelsProtos.VisibilityLabelsService;
 import org.apache.hadoop.hbase.util.ByteStringer;
 import org.apache.hadoop.hbase.util.Bytes;
+import org.apache.yetus.audience.InterfaceAudience;
 
-import com.google.protobuf.ByteString;
-import com.google.protobuf.ServiceException;
 
 /**
  * Utility client for doing visibility labels admin operations.
@@ -122,7 +123,6 @@ public class VisibilityClient {
    */
   public static VisibilityLabelsResponse addLabels(Connection connection, final String[] labels)
       throws Throwable {
-
     try (Table table = connection.getTable(LABELS_TABLE_NAME)) {
       Batch.Call<VisibilityLabelsService, VisibilityLabelsResponse> callable =
           new Batch.Call<VisibilityLabelsService, VisibilityLabelsResponse>() {
@@ -130,8 +130,8 @@ public class VisibilityClient {
         CoprocessorRpcUtils.BlockingRpcCallback<VisibilityLabelsResponse> rpcCallback =
             new CoprocessorRpcUtils.BlockingRpcCallback<>();
 
-            public VisibilityLabelsResponse call(VisibilityLabelsService service)
+        @Override
-                throws IOException {
+        public VisibilityLabelsResponse call(VisibilityLabelsService service) throws IOException {
           VisibilityLabelsRequest.Builder builder = VisibilityLabelsRequest.newBuilder();
           for (String label : labels) {
             if (label.length() > 0) {
@@ -215,6 +215,7 @@ public class VisibilityClient {
         CoprocessorRpcUtils.BlockingRpcCallback<GetAuthsResponse> rpcCallback =
             new CoprocessorRpcUtils.BlockingRpcCallback<>();
 
+        @Override
         public GetAuthsResponse call(VisibilityLabelsService service) throws IOException {
           GetAuthsRequest.Builder getAuthReqBuilder = GetAuthsRequest.newBuilder();
           getAuthReqBuilder.setUser(ByteStringer.wrap(Bytes.toBytes(user)));
@@ -227,8 +228,8 @@ public class VisibilityClient {
         }
       };
       Map<byte[], GetAuthsResponse> result =
-          table.coprocessorService(VisibilityLabelsService.class,
+          table.coprocessorService(VisibilityLabelsService.class, HConstants.EMPTY_BYTE_ARRAY,
-            HConstants.EMPTY_BYTE_ARRAY, HConstants.EMPTY_BYTE_ARRAY, callable);
+              HConstants.EMPTY_BYTE_ARRAY, callable);
       return result.values().iterator().next(); // There will be exactly one region for labels
       // table and so one entry in result Map.
     }
@@ -266,6 +267,7 @@ public class VisibilityClient {
         CoprocessorRpcUtils.BlockingRpcCallback<ListLabelsResponse> rpcCallback =
             new CoprocessorRpcUtils.BlockingRpcCallback<>();
 
+        @Override
         public ListLabelsResponse call(VisibilityLabelsService service) throws IOException {
           ListLabelsRequest.Builder listAuthLabelsReqBuilder = ListLabelsRequest.newBuilder();
           if (regex != null) {
@@ -330,6 +332,7 @@ public class VisibilityClient {
         CoprocessorRpcUtils.BlockingRpcCallback<VisibilityLabelsResponse> rpcCallback =
             new CoprocessorRpcUtils.BlockingRpcCallback<>();
 
+        @Override
         public VisibilityLabelsResponse call(VisibilityLabelsService service) throws IOException {
           SetAuthsRequest.Builder setAuthReqBuilder = SetAuthsRequest.newBuilder();
           setAuthReqBuilder.setUser(ByteStringer.wrap(Bytes.toBytes(user)));

hbase-client/src/main/java/org/apache/hadoop/hbase/shaded/protobuf/ResponseConverter.java

@@ -417,7 +417,7 @@ public final class ResponseConverter {
 
   public static Map<String, Long> getScanMetrics(ScanResponse response) {
     Map<String, Long> metricMap = new HashMap<>();
-    if (response == null || !response.hasScanMetrics() || response.getScanMetrics() == null) {
+    if (response == null || !response.hasScanMetrics()) {
       return metricMap;
     }
 

hbase-client/src/main/java/org/apache/hadoop/hbase/util/PoolMap.java

@@ -298,7 +298,7 @@ public class PoolMap<K, V> implements Map<K, V> {
    *          the type of the resource
    */
   @SuppressWarnings("serial")
-  public class ReusablePool<R> extends ConcurrentLinkedQueue<R> implements Pool<R> {
+  public static class ReusablePool<R> extends ConcurrentLinkedQueue<R> implements Pool<R> {
     private int maxSize;
 
     public ReusablePool(int maxSize) {
@@ -342,7 +342,7 @@ public class PoolMap<K, V> implements Map<K, V> {
    *
    */
   @SuppressWarnings("serial")
-  class RoundRobinPool<R> extends CopyOnWriteArrayList<R> implements Pool<R> {
+  static class RoundRobinPool<R> extends CopyOnWriteArrayList<R> implements Pool<R> {
     private int maxSize;
     private int nextResource = 0;
 

hbase-client/src/test/java/org/apache/hadoop/hbase/TestHColumnDescriptor.java

@@ -20,6 +20,8 @@ package org.apache.hadoop.hbase;
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertTrue;
 
+import java.nio.charset.StandardCharsets;
+
 import org.apache.hadoop.hbase.exceptions.DeserializationException;
 import org.apache.hadoop.hbase.exceptions.HBaseException;
 import org.apache.hadoop.hbase.io.compress.Compression;
@@ -32,13 +34,17 @@ import org.apache.hadoop.hbase.testclassification.MiscTests;
 import org.apache.hadoop.hbase.testclassification.SmallTests;
 import org.apache.hadoop.hbase.util.BuilderStyleTest;
 import org.junit.Assert;
+import org.junit.Rule;
 import org.junit.Test;
 import org.junit.experimental.categories.Category;
+import org.junit.rules.ExpectedException;
 
 /** Tests the HColumnDescriptor with appropriate arguments */
 @Category({MiscTests.class, SmallTests.class})
 @Deprecated
 public class TestHColumnDescriptor {
+  @Rule
+  public ExpectedException expectedEx = ExpectedException.none();
   @Test
   public void testPb() throws DeserializationException {
     HColumnDescriptor hcd = new HColumnDescriptor(
@@ -87,15 +93,14 @@ public class TestHColumnDescriptor {
     assertEquals(v, deserializedHcd.getDFSReplication());
   }
 
+  /**
+   * Tests HColumnDescriptor with empty familyName
+   */
   @Test
-  /** Tests HColumnDescriptor with empty familyName*/
+  public void testHColumnDescriptorShouldThrowIAEWhenFamilyNameEmpty() throws Exception {
-  public void testHColumnDescriptorShouldThrowIAEWhenFamiliyNameEmpty()
+    expectedEx.expect(IllegalArgumentException.class);
-      throws Exception {
+    expectedEx.expectMessage("Column Family name can not be empty");
-    try {
+    new HColumnDescriptor("".getBytes(StandardCharsets.UTF_8));
-      new HColumnDescriptor("".getBytes());
-    } catch (IllegalArgumentException e) {
-      assertEquals("Column Family name can not be empty", e.getLocalizedMessage());
-    }
   }
 
   /**

hbase-client/src/test/java/org/apache/hadoop/hbase/TestHTableDescriptor.java

@@ -108,7 +108,7 @@ public class TestHTableDescriptor {
     assertEquals(v, deserializedHtd.getMaxFileSize());
     assertTrue(deserializedHtd.isReadOnly());
     assertEquals(Durability.ASYNC_WAL, deserializedHtd.getDurability());
-    assertEquals(deserializedHtd.getRegionReplication(), 2);
+    assertEquals(2, deserializedHtd.getRegionReplication());
   }
 
   /**

hbase-client/src/test/java/org/apache/hadoop/hbase/TestInterfaceAudienceAnnotations.java

@@ -75,14 +75,14 @@ public class TestInterfaceAudienceAnnotations {
   private static final Log LOG = LogFactory.getLog(TestInterfaceAudienceAnnotations.class);
 
   /** Selects classes with generated in their package name */
-  class GeneratedClassFilter implements ClassFinder.ClassFilter {
+  static class GeneratedClassFilter implements ClassFinder.ClassFilter {
     @Override
     public boolean isCandidateClass(Class<?> c) {
       return c.getPackage().getName().contains("generated");
     }
   }
 
-  class ShadedProtobufClassFilter implements ClassFinder.ClassFilter {
+  static class ShadedProtobufClassFilter implements ClassFinder.ClassFilter {
     @Override
     public boolean isCandidateClass(Class<?> c) {
       return c.getPackage().getName().
@@ -242,7 +242,7 @@ public class TestInterfaceAudienceAnnotations {
   }
 
   /** Selects classes that are declared public */
-  class PublicClassFilter implements ClassFinder.ClassFilter {
+  static class PublicClassFilter implements ClassFinder.ClassFilter {
     @Override
     public boolean isCandidateClass(Class<?> c) {
       int mod = c.getModifiers();
@@ -251,7 +251,7 @@ public class TestInterfaceAudienceAnnotations {
   }
 
   /** Selects paths (jars and class dirs) only from the main code, not test classes */
-  class MainCodeResourcePathFilter implements ClassFinder.ResourcePathFilter {
+  static class MainCodeResourcePathFilter implements ClassFinder.ResourcePathFilter {
     @Override
     public boolean isCandidatePath(String resourcePath, boolean isJar) {
       return !resourcePath.contains("test-classes") &&
@@ -268,7 +268,7 @@ public class TestInterfaceAudienceAnnotations {
    * - enclosing class is not an interface
    * - name starts with "__CLR"
    */
-  class CloverInstrumentationFilter implements ClassFinder.ClassFilter {
+  static class CloverInstrumentationFilter implements ClassFinder.ClassFilter {
     @Override
     public boolean isCandidateClass(Class<?> clazz) {
       boolean clover = false;

hbase-client/src/test/java/org/apache/hadoop/hbase/client/TestAsyncProcess.java

@@ -1,5 +1,4 @@
 /*
- *
  * Licensed to the Apache Software Foundation (ASF) under one
  * or more contributor license agreements.  See the NOTICE file
  * distributed with this work for additional information
@@ -25,6 +24,7 @@ import static org.junit.Assert.assertTrue;
 
 import java.io.IOException;
 import java.io.InterruptedIOException;
+import java.nio.charset.StandardCharsets;
 import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.Collections;
@@ -88,12 +88,13 @@ public class TestAsyncProcess {
   private static final Log LOG = LogFactory.getLog(TestAsyncProcess.class);
   private static final TableName DUMMY_TABLE =
       TableName.valueOf("DUMMY_TABLE");
-  private static final byte[] DUMMY_BYTES_1 = "DUMMY_BYTES_1".getBytes();
+  private static final byte[] DUMMY_BYTES_1 = "DUMMY_BYTES_1".getBytes(StandardCharsets.UTF_8);
-  private static final byte[] DUMMY_BYTES_2 = "DUMMY_BYTES_2".getBytes();
+  private static final byte[] DUMMY_BYTES_2 = "DUMMY_BYTES_2".getBytes(StandardCharsets.UTF_8);
-  private static final byte[] DUMMY_BYTES_3 = "DUMMY_BYTES_3".getBytes();
+  private static final byte[] DUMMY_BYTES_3 = "DUMMY_BYTES_3".getBytes(StandardCharsets.UTF_8);
-  private static final byte[] FAILS = "FAILS".getBytes();
+  private static final byte[] FAILS = "FAILS".getBytes(StandardCharsets.UTF_8);
   private static final Configuration CONF = new Configuration();
-  private static final ConnectionConfiguration CONNECTION_CONFIG = new ConnectionConfiguration(CONF);
+  private static final ConnectionConfiguration CONNECTION_CONFIG =
+      new ConnectionConfiguration(CONF);
   private static final ServerName sn = ServerName.valueOf("s1,1,1");
   private static final ServerName sn2 = ServerName.valueOf("s2,2,2");
   private static final ServerName sn3 = ServerName.valueOf("s3,3,3");
@@ -115,7 +116,8 @@ public class TestAsyncProcess {
       new HRegionLocation(hri1r1, sn2), new HRegionLocation(hri1r2, sn3));
   private static final RegionLocations hrls2 = new RegionLocations(new HRegionLocation(hri2, sn2),
       new HRegionLocation(hri2r1, sn3));
-  private static final RegionLocations hrls3 = new RegionLocations(new HRegionLocation(hri3, sn3), null);
+  private static final RegionLocations hrls3 =
+      new RegionLocations(new HRegionLocation(hri3, sn3), null);
 
   private static final String success = "success";
   private static Exception failure = new Exception("failure");
@@ -325,7 +327,7 @@ public class TestAsyncProcess {
     public AsyncProcessWithFailure(ClusterConnection hc, Configuration conf, IOException ioe) {
       super(hc, conf, true);
       this.ioe = ioe;
-      serverTrackerTimeout = 1;
+      serverTrackerTimeout = 1L;
     }
 
     @Override
@@ -351,7 +353,8 @@ public class TestAsyncProcess {
       return inc.getAndIncrement();
     }
   }
-  class MyAsyncProcessWithReplicas extends MyAsyncProcess {
+
+  static class MyAsyncProcessWithReplicas extends MyAsyncProcess {
     private Set<byte[]> failures = new TreeSet<>(new Bytes.ByteArrayComparator());
     private long primarySleepMs = 0, replicaSleepMs = 0;
     private Map<ServerName, Long> customPrimarySleepMs = new HashMap<>();
@@ -589,7 +592,13 @@ public class TestAsyncProcess {
     Random rn = new Random();
     final long limit = 10 * 1024 * 1024;
     final int requestCount = 1 + (int) (rn.nextDouble() * 3);
-    long putsHeapSize = Math.abs(rn.nextLong()) % limit;
+    long n = rn.nextLong();
+    if (n < 0) {
+      n = -n;
+    } else if (n == 0) {
+      n = 1;
+    }
+    long putsHeapSize = n % limit;
     long maxHeapSizePerRequest = putsHeapSize / requestCount;
     LOG.info("[testSubmitRandomSizeRequest] maxHeapSizePerRequest=" + maxHeapSizePerRequest +
         ", putsHeapSize=" + putsHeapSize);
@@ -612,13 +621,15 @@ public class TestAsyncProcess {
 
   private void doSubmitRequest(long maxHeapSizePerRequest, long putsHeapSize) throws Exception {
     ClusterConnection conn = createHConnection();
-    final String defaultClazz = conn.getConfiguration().get(RequestControllerFactory.REQUEST_CONTROLLER_IMPL_CONF_KEY);
+    final String defaultClazz =
+        conn.getConfiguration().get(RequestControllerFactory.REQUEST_CONTROLLER_IMPL_CONF_KEY);
     final long defaultHeapSizePerRequest = conn.getConfiguration().getLong(
       SimpleRequestController.HBASE_CLIENT_MAX_PERREQUEST_HEAPSIZE,
       SimpleRequestController.DEFAULT_HBASE_CLIENT_MAX_PERREQUEST_HEAPSIZE);
     conn.getConfiguration().set(RequestControllerFactory.REQUEST_CONTROLLER_IMPL_CONF_KEY,
       SimpleRequestController.class.getName());
-    conn.getConfiguration().setLong(SimpleRequestController.HBASE_CLIENT_MAX_PERREQUEST_HEAPSIZE, maxHeapSizePerRequest);
+    conn.getConfiguration().setLong(SimpleRequestController.HBASE_CLIENT_MAX_PERREQUEST_HEAPSIZE,
+        maxHeapSizePerRequest);
 
     // sn has two regions
     long putSizeSN = 0;
@@ -640,7 +651,8 @@ public class TestAsyncProcess {
 
     int minCountSnRequest = (int) calculateRequestCount(putSizeSN, maxHeapSizePerRequest);
     int minCountSn2Request = (int) calculateRequestCount(putSizeSN2, maxHeapSizePerRequest);
-    LOG.info("Total put count:" + puts.size() + ", putSizeSN:"+ putSizeSN + ", putSizeSN2:" + putSizeSN2
+    LOG.info("Total put count:" + puts.size() + ", putSizeSN:"+ putSizeSN
+        + ", putSizeSN2:" + putSizeSN2
         + ", maxHeapSizePerRequest:" + maxHeapSizePerRequest
         + ", minCountSnRequest:" + minCountSnRequest
         + ", minCountSn2Request:" + minCountSn2Request);
@@ -683,7 +695,7 @@ public class TestAsyncProcess {
             sum += size;
           }
           assertEquals(true, sum <= maxHeapSizePerRequest);
-          long value = sizePerServers.containsKey(entry.getKey()) ? sizePerServers.get(entry.getKey()) : 0L;
+          long value = sizePerServers.getOrDefault(entry.getKey(), 0L);
           sizePerServers.put(entry.getKey(), value + sum);
         }
       }
@@ -694,7 +706,8 @@ public class TestAsyncProcess {
       assertEquals(putSizeSN2, (long) sizePerServers.get(sn2));
     }
     // restore config.
-    conn.getConfiguration().setLong(SimpleRequestController.HBASE_CLIENT_MAX_PERREQUEST_HEAPSIZE, defaultHeapSizePerRequest);
+    conn.getConfiguration().setLong(SimpleRequestController.HBASE_CLIENT_MAX_PERREQUEST_HEAPSIZE,
+        defaultHeapSizePerRequest);
     if (defaultClazz != null) {
       conn.getConfiguration().set(RequestControllerFactory.REQUEST_CONTROLLER_IMPL_CONF_KEY,
         defaultClazz);
@@ -731,13 +744,14 @@ public class TestAsyncProcess {
     final AsyncRequestFuture ars = ap.submit(null, DUMMY_TABLE, puts, false, cb, false);
     Assert.assertTrue(puts.isEmpty());
     ars.waitUntilDone();
-    Assert.assertEquals(updateCalled.get(), 1);
+    Assert.assertEquals(1, updateCalled.get());
   }
 
   @Test
   public void testSubmitBusyRegion() throws Exception {
     ClusterConnection conn = createHConnection();
-    final String defaultClazz = conn.getConfiguration().get(RequestControllerFactory.REQUEST_CONTROLLER_IMPL_CONF_KEY);
+    final String defaultClazz =
+        conn.getConfiguration().get(RequestControllerFactory.REQUEST_CONTROLLER_IMPL_CONF_KEY);
     conn.getConfiguration().set(RequestControllerFactory.REQUEST_CONTROLLER_IMPL_CONF_KEY,
       SimpleRequestController.class.getName());
     MyAsyncProcess ap = new MyAsyncProcess(conn, CONF);
@@ -765,11 +779,13 @@ public class TestAsyncProcess {
   public void testSubmitBusyRegionServer() throws Exception {
     ClusterConnection conn = createHConnection();
     MyAsyncProcess ap = new MyAsyncProcess(conn, CONF);
-    final String defaultClazz = conn.getConfiguration().get(RequestControllerFactory.REQUEST_CONTROLLER_IMPL_CONF_KEY);
+    final String defaultClazz =
+        conn.getConfiguration().get(RequestControllerFactory.REQUEST_CONTROLLER_IMPL_CONF_KEY);
     conn.getConfiguration().set(RequestControllerFactory.REQUEST_CONTROLLER_IMPL_CONF_KEY,
       SimpleRequestController.class.getName());
     SimpleRequestController controller = (SimpleRequestController) ap.requestController;
-    controller.taskCounterPerServer.put(sn2, new AtomicInteger(controller.maxConcurrentTasksPerServer));
+    controller.taskCounterPerServer.put(sn2,
+        new AtomicInteger(controller.maxConcurrentTasksPerServer));
 
     List<Put> puts = new ArrayList<>(4);
     puts.add(createPut(1, true));
@@ -780,7 +796,8 @@ public class TestAsyncProcess {
     ap.submit(null, DUMMY_TABLE, puts, false, null, false);
     Assert.assertEquals(" puts=" + puts, 1, puts.size());
 
-    controller.taskCounterPerServer.put(sn2, new AtomicInteger(controller.maxConcurrentTasksPerServer - 1));
+    controller.taskCounterPerServer.put(sn2,
+        new AtomicInteger(controller.maxConcurrentTasksPerServer - 1));
     ap.submit(null, DUMMY_TABLE, puts, false, null, false);
     Assert.assertTrue(puts.isEmpty());
     if (defaultClazz != null) {
@@ -819,7 +836,8 @@ public class TestAsyncProcess {
   public void testSubmitTrue() throws IOException {
     ClusterConnection conn = createHConnection();
     final MyAsyncProcess ap = new MyAsyncProcess(conn, CONF, false);
-    final String defaultClazz = conn.getConfiguration().get(RequestControllerFactory.REQUEST_CONTROLLER_IMPL_CONF_KEY);
+    final String defaultClazz =
+        conn.getConfiguration().get(RequestControllerFactory.REQUEST_CONTROLLER_IMPL_CONF_KEY);
     conn.getConfiguration().set(RequestControllerFactory.REQUEST_CONTROLLER_IMPL_CONF_KEY,
       SimpleRequestController.class.getName());
     SimpleRequestController controller = (SimpleRequestController) ap.requestController;
@@ -923,7 +941,8 @@ public class TestAsyncProcess {
     Mockito.when(conn.getConfiguration()).thenReturn(copyConf);
     Mockito.when(conn.getStatisticsTracker()).thenReturn(ServerStatisticTracker.create(copyConf));
     Mockito.when(conn.getBackoffPolicy()).thenReturn(bp);
-    final String defaultClazz = conn.getConfiguration().get(RequestControllerFactory.REQUEST_CONTROLLER_IMPL_CONF_KEY);
+    final String defaultClazz =
+        conn.getConfiguration().get(RequestControllerFactory.REQUEST_CONTROLLER_IMPL_CONF_KEY);
     conn.getConfiguration().set(RequestControllerFactory.REQUEST_CONTROLLER_IMPL_CONF_KEY,
       SimpleRequestController.class.getName());
     MyAsyncProcess ap = new MyAsyncProcess(conn, copyConf, false);
@@ -934,7 +953,8 @@ public class TestAsyncProcess {
     }
   }
 
-  private void testTaskCount(MyAsyncProcess ap) throws InterruptedIOException, InterruptedException {
+  private void testTaskCount(MyAsyncProcess ap)
+      throws InterruptedIOException, InterruptedException {
     SimpleRequestController controller = (SimpleRequestController) ap.requestController;
     List<Put> puts = new ArrayList<>();
     for (int i = 0; i != 3; ++i) {
@@ -958,7 +978,8 @@ public class TestAsyncProcess {
   @Test
   public void testMaxTask() throws Exception {
     ClusterConnection conn = createHConnection();
-    final String defaultClazz = conn.getConfiguration().get(RequestControllerFactory.REQUEST_CONTROLLER_IMPL_CONF_KEY);
+    final String defaultClazz =
+        conn.getConfiguration().get(RequestControllerFactory.REQUEST_CONTROLLER_IMPL_CONF_KEY);
     conn.getConfiguration().set(RequestControllerFactory.REQUEST_CONTROLLER_IMPL_CONF_KEY,
       SimpleRequestController.class.getName());
     final MyAsyncProcess ap = new MyAsyncProcess(conn, CONF, false);
@@ -966,7 +987,7 @@ public class TestAsyncProcess {
 
 
     for (int i = 0; i < 1000; i++) {
-      ap.incTaskCounters(Collections.singleton("dummy".getBytes()), sn);
+      ap.incTaskCounters(Collections.singleton("dummy".getBytes(StandardCharsets.UTF_8)), sn);
     }
 
     final Thread myThread = Thread.currentThread();
@@ -997,7 +1018,7 @@ public class TestAsyncProcess {
       public void run() {
         Threads.sleep(sleepTime);
         while (controller.tasksInProgress.get() > 0) {
-          ap.decTaskCounters(Collections.singleton("dummy".getBytes()), sn);
+          ap.decTaskCounters(Collections.singleton("dummy".getBytes(StandardCharsets.UTF_8)), sn);
         }
       }
     };
@@ -1020,8 +1041,8 @@ public class TestAsyncProcess {
     setMockLocation(hc, DUMMY_BYTES_1, new RegionLocations(loc1));
     setMockLocation(hc, DUMMY_BYTES_2, new RegionLocations(loc2));
     setMockLocation(hc, DUMMY_BYTES_3, new RegionLocations(loc3));
-    Mockito.when(hc.locateRegions(Mockito.eq(DUMMY_TABLE), Mockito.anyBoolean(), Mockito.anyBoolean()))
+    Mockito.when(hc.locateRegions(Mockito.eq(DUMMY_TABLE), Mockito.anyBoolean(),
-           .thenReturn(Arrays.asList(loc1, loc2, loc3));
+        Mockito.anyBoolean())).thenReturn(Arrays.asList(loc1, loc2, loc3));
     setMockLocation(hc, FAILS, new RegionLocations(loc2));
     return hc;
   }
@@ -1041,8 +1062,8 @@ public class TestAsyncProcess {
     for (HRegionLocation loc : hrls3.getRegionLocations()) {
       locations.add(loc);
     }
-    Mockito.when(hc.locateRegions(Mockito.eq(DUMMY_TABLE), Mockito.anyBoolean(), Mockito.anyBoolean()))
+    Mockito.when(hc.locateRegions(Mockito.eq(DUMMY_TABLE), Mockito.anyBoolean(),
-           .thenReturn(locations);
+        Mockito.anyBoolean())).thenReturn(locations);
     return hc;
   }
 
@@ -1073,7 +1094,8 @@ public class TestAsyncProcess {
 
     Put put = createPut(1, true);
 
-    Assert.assertEquals(conn.getConnectionConfiguration().getWriteBufferSize(), ht.getWriteBufferSize());
+    Assert.assertEquals(conn.getConnectionConfiguration().getWriteBufferSize(),
+        ht.getWriteBufferSize());
     Assert.assertEquals(0, ht.getCurrentWriteBufferSize());
     ht.mutate(put);
     ht.flush();
@@ -1161,13 +1183,13 @@ public class TestAsyncProcess {
     } catch (RetriesExhaustedException expected) {
     }
 
-    Assert.assertEquals(res[0], success);
+    Assert.assertEquals(success, res[0]);
-    Assert.assertEquals(res[1], success);
+    Assert.assertEquals(success, res[1]);
-    Assert.assertEquals(res[2], success);
+    Assert.assertEquals(success, res[2]);
-    Assert.assertEquals(res[3], success);
+    Assert.assertEquals(success, res[3]);
-    Assert.assertEquals(res[4], failure);
+    Assert.assertEquals(failure, res[4]);
-    Assert.assertEquals(res[5], success);
+    Assert.assertEquals(success, res[5]);
-    Assert.assertEquals(res[6], failure);
+    Assert.assertEquals(failure, res[6]);
   }
   @Test
   public void testErrorsServers() throws IOException {
@@ -1179,8 +1201,8 @@ public class TestAsyncProcess {
     configuration.setBoolean(ConnectionImplementation.RETRIES_BY_SERVER_KEY, true);
 
     Assert.assertNotNull(ap.createServerErrorTracker());
-    Assert.assertTrue(ap.serverTrackerTimeout > 200);
+    Assert.assertTrue(ap.serverTrackerTimeout > 200L);
-    ap.serverTrackerTimeout = 1;
+    ap.serverTrackerTimeout = 1L;
 
     Put p = createPut(1, false);
     mutator.mutate(p);
@@ -1258,7 +1280,8 @@ public class TestAsyncProcess {
   @Test
   public void testCallQueueTooLarge() throws IOException {
     ClusterConnection conn = new MyConnectionImpl(CONF);
-    AsyncProcessWithFailure ap = new AsyncProcessWithFailure(conn, CONF, new CallQueueTooBigException());
+    AsyncProcessWithFailure ap =
+        new AsyncProcessWithFailure(conn, CONF, new CallQueueTooBigException());
     BufferedMutatorParams bufferParam = createBufferedMutatorParams(ap, DUMMY_TABLE);
     BufferedMutatorImpl mutator = new BufferedMutatorImpl(conn, bufferParam, ap);
     Assert.assertNotNull(ap.createServerErrorTracker());
@@ -1298,7 +1321,7 @@ public class TestAsyncProcess {
     ht.multiAp = ap;
     ht.batch(gets, null);
 
-    Assert.assertEquals(ap.nbActions.get(), NB_REGS);
+    Assert.assertEquals(NB_REGS, ap.nbActions.get());
     Assert.assertEquals("1 multi response per server", 2, ap.nbMultiResponse.get());
     Assert.assertEquals("1 thread per server", 2, con.nbThreads.get());
 
@@ -1306,7 +1329,7 @@ public class TestAsyncProcess {
     for (int i =0; i<NB_REGS; i++){
       if (con.usedRegions[i]) nbReg++;
     }
-    Assert.assertEquals("nbReg=" + nbReg, nbReg, NB_REGS);
+    Assert.assertEquals("nbReg=" + nbReg, NB_REGS, nbReg);
   }
 
   @Test
@@ -1479,7 +1502,8 @@ public class TestAsyncProcess {
     return ap;
   }
 
-  private static BufferedMutatorParams createBufferedMutatorParams(MyAsyncProcess ap, TableName name) {
+  private static BufferedMutatorParams createBufferedMutatorParams(MyAsyncProcess ap,
+      TableName name) {
     return new BufferedMutatorParams(name)
             .pool(ap.service)
             .rpcTimeout(RPC_TIMEOUT)

hbase-client/src/test/java/org/apache/hadoop/hbase/client/TestBufferedMutatorParams.java

@@ -49,57 +49,69 @@ public class TestBufferedMutatorParams {
    */
   private class MockExecutorService implements ExecutorService {
 
+    @Override
     public void execute(Runnable command) {
     }
 
+    @Override
     public void shutdown() {
     }
 
+    @Override
     public List<Runnable> shutdownNow() {
       return null;
     }
 
+    @Override
     public boolean isShutdown() {
       return false;
     }
 
+    @Override
     public boolean isTerminated() {
       return false;
     }
 
-    public boolean awaitTermination(long timeout, TimeUnit unit)
+    @Override
-        throws InterruptedException {
+    public boolean awaitTermination(long timeout, TimeUnit unit) throws InterruptedException {
       return false;
     }
 
+    @Override
     public <T> Future<T> submit(Callable<T> task) {
       return null;
     }
 
+    @Override
     public <T> Future<T> submit(Runnable task, T result) {
       return null;
     }
 
+    @Override
     public Future<?> submit(Runnable task) {
       return null;
     }
 
+    @Override
     public <T> List<Future<T>> invokeAll(
         Collection<? extends Callable<T>> tasks) throws InterruptedException {
       return null;
     }
 
+    @Override
     public <T> List<Future<T>> invokeAll(
         Collection<? extends Callable<T>> tasks, long timeout, TimeUnit unit)
         throws InterruptedException {
       return null;
     }
 
+    @Override
     public <T> T invokeAny(Collection<? extends Callable<T>> tasks)
         throws InterruptedException, ExecutionException {
       return null;
     }
 
+    @Override
     public <T> T invokeAny(Collection<? extends Callable<T>> tasks,
         long timeout, TimeUnit unit)
         throws InterruptedException, ExecutionException, TimeoutException {
@@ -110,8 +122,8 @@ public class TestBufferedMutatorParams {
   /**
    * Just to create an instance, this doesn't actually function.
    */
-  private class MockExceptionListener
+  private static class MockExceptionListener implements BufferedMutator.ExceptionListener {
-      implements BufferedMutator.ExceptionListener {
+    @Override
     public void onException(RetriesExhaustedWithDetailsException exception,
         BufferedMutator mutator) throws RetriesExhaustedWithDetailsException {
     }

hbase-client/src/test/java/org/apache/hadoop/hbase/client/TestClientExponentialBackoff.java

@@ -126,8 +126,8 @@ public class TestClientExponentialBackoff {
 
     update(stats, 0, 98, 0);
     backoffTime = backoff.getBackoffTime(server, regionname, stats);
-    assertEquals("We should be using max backoff when at high watermark", backoffTime,
+    assertEquals("We should be using max backoff when at high watermark",
-      ExponentialClientBackoffPolicy.DEFAULT_MAX_BACKOFF);
+      ExponentialClientBackoffPolicy.DEFAULT_MAX_BACKOFF, backoffTime);
   }
 
   @Test
@@ -150,8 +150,8 @@ public class TestClientExponentialBackoff {
 
     update(stats, 0, 0, 100);
     backoffTime = backoff.getBackoffTime(server, regionname, stats);
-    assertEquals("under heavy compaction pressure", backoffTime,
+    assertEquals("under heavy compaction pressure",
-            ExponentialClientBackoffPolicy.DEFAULT_MAX_BACKOFF);
+      ExponentialClientBackoffPolicy.DEFAULT_MAX_BACKOFF, backoffTime);
   }
 
   private void update(ServerStatistics stats, int load) {

hbase-client/src/test/java/org/apache/hadoop/hbase/client/TestClientScanner.java

@@ -30,6 +30,7 @@ import static org.mockito.Matchers.anyInt;
 import static org.mockito.Mockito.when;
 
 import java.io.IOException;
+import java.nio.charset.StandardCharsets;
 import java.util.Iterator;
 import java.util.concurrent.ExecutorService;
 import java.util.concurrent.Executors;
@@ -131,7 +132,8 @@ public class TestClientScanner {
   @SuppressWarnings("unchecked")
   public void testNoResultsHint() throws IOException {
     final Result[] results = new Result[1];
-    KeyValue kv1 = new KeyValue("row".getBytes(), "cf".getBytes(), "cq".getBytes(), 1,
+    KeyValue kv1 = new KeyValue("row".getBytes(StandardCharsets.UTF_8),
+        "cf".getBytes(StandardCharsets.UTF_8), "cq".getBytes(StandardCharsets.UTF_8), 1,
         Type.Maximum);
     results[0] = Result.create(new Cell[] {kv1});
 
@@ -191,7 +193,8 @@ public class TestClientScanner {
   @SuppressWarnings("unchecked")
   public void testSizeLimit() throws IOException {
     final Result[] results = new Result[1];
-    KeyValue kv1 = new KeyValue("row".getBytes(), "cf".getBytes(), "cq".getBytes(), 1,
+    KeyValue kv1 = new KeyValue("row".getBytes(StandardCharsets.UTF_8),
+      "cf".getBytes(StandardCharsets.UTF_8), "cq".getBytes(StandardCharsets.UTF_8), 1,
         Type.Maximum);
     results[0] = Result.create(new Cell[] {kv1});
 
@@ -248,9 +251,14 @@ public class TestClientScanner {
   @Test
   @SuppressWarnings("unchecked")
   public void testCacheLimit() throws IOException {
-    KeyValue kv1 = new KeyValue("row1".getBytes(), "cf".getBytes(), "cq".getBytes(), 1,
+    KeyValue kv1 = new KeyValue("row1".getBytes(StandardCharsets.UTF_8),
-        Type.Maximum), kv2 = new KeyValue("row2".getBytes(), "cf".getBytes(), "cq".getBytes(), 1,
+      "cf".getBytes(StandardCharsets.UTF_8), "cq".getBytes(StandardCharsets.UTF_8), 1,
-        Type.Maximum), kv3 = new KeyValue("row3".getBytes(), "cf".getBytes(), "cq".getBytes(), 1,
+        Type.Maximum);
+    KeyValue kv2 = new KeyValue("row2".getBytes(StandardCharsets.UTF_8),
+        "cf".getBytes(StandardCharsets.UTF_8), "cq".getBytes(StandardCharsets.UTF_8), 1,
+        Type.Maximum);
+    KeyValue kv3 = new KeyValue("row3".getBytes(StandardCharsets.UTF_8),
+        "cf".getBytes(StandardCharsets.UTF_8), "cq".getBytes(StandardCharsets.UTF_8), 1,
         Type.Maximum);
     final Result[] results = new Result[] {Result.create(new Cell[] {kv1}),
         Result.create(new Cell[] {kv2}), Result.create(new Cell[] {kv3})};
@@ -323,7 +331,8 @@ public class TestClientScanner {
   @SuppressWarnings("unchecked")
   public void testNoMoreResults() throws IOException {
     final Result[] results = new Result[1];
-    KeyValue kv1 = new KeyValue("row".getBytes(), "cf".getBytes(), "cq".getBytes(), 1,
+    KeyValue kv1 = new KeyValue("row".getBytes(StandardCharsets.UTF_8),
+      "cf".getBytes(StandardCharsets.UTF_8), "cq".getBytes(StandardCharsets.UTF_8), 1,
         Type.Maximum);
     results[0] = Result.create(new Cell[] {kv1});
 
@@ -381,12 +390,14 @@ public class TestClientScanner {
   @SuppressWarnings("unchecked")
   public void testMoreResults() throws IOException {
     final Result[] results1 = new Result[1];
-    KeyValue kv1 = new KeyValue("row".getBytes(), "cf".getBytes(), "cq".getBytes(), 1,
+    KeyValue kv1 = new KeyValue("row".getBytes(StandardCharsets.UTF_8),
+        "cf".getBytes(StandardCharsets.UTF_8), "cq".getBytes(StandardCharsets.UTF_8), 1,
         Type.Maximum);
     results1[0] = Result.create(new Cell[] {kv1});
 
     final Result[] results2 = new Result[1];
-    KeyValue kv2 = new KeyValue("row2".getBytes(), "cf".getBytes(), "cq".getBytes(), 1,
+    KeyValue kv2 = new KeyValue("row2".getBytes(StandardCharsets.UTF_8),
+      "cf".getBytes(StandardCharsets.UTF_8), "cq".getBytes(StandardCharsets.UTF_8), 1,
         Type.Maximum);
     results2[0] = Result.create(new Cell[] {kv2});
 

hbase-client/src/test/java/org/apache/hadoop/hbase/client/TestColumnFamilyDescriptorBuilder.java

@@ -17,6 +17,9 @@
  */
 package org.apache.hadoop.hbase.client;
 
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertTrue;
+
 import org.apache.hadoop.hbase.HColumnDescriptor;
 import org.apache.hadoop.hbase.HConstants;
 import org.apache.hadoop.hbase.KeepDeletedCells;
@@ -32,13 +35,17 @@ import org.apache.hadoop.hbase.util.BuilderStyleTest;
 import org.apache.hadoop.hbase.util.Bytes;
 import org.apache.hadoop.hbase.util.PrettyPrinter;
 import org.junit.Assert;
-import static org.junit.Assert.assertEquals;
+import org.junit.Rule;
-import static org.junit.Assert.assertTrue;
 import org.junit.Test;
 import org.junit.experimental.categories.Category;
+import org.junit.rules.ExpectedException;
 
 @Category({MiscTests.class, SmallTests.class})
 public class TestColumnFamilyDescriptorBuilder {
+
+  @Rule
+  public ExpectedException expectedEx = ExpectedException.none();
+
   @Test
   public void testBuilder() throws DeserializationException {
     ColumnFamilyDescriptorBuilder builder
@@ -86,15 +93,14 @@ public class TestColumnFamilyDescriptorBuilder {
     assertEquals(v, deserializedHcd.getDFSReplication());
   }
 
+  /**
+   * Tests HColumnDescriptor with empty familyName
+   */
   @Test
-  /** Tests HColumnDescriptor with empty familyName*/
+  public void testHColumnDescriptorShouldThrowIAEWhenFamilyNameEmpty() throws Exception {
-  public void testHColumnDescriptorShouldThrowIAEWhenFamiliyNameEmpty()
+    expectedEx.expect(IllegalArgumentException.class);
-      throws Exception {
+    expectedEx.expectMessage("Column Family name can not be empty");
-    try {
     ColumnFamilyDescriptorBuilder.of("");
-    } catch (IllegalArgumentException e) {
-      assertEquals("Column Family name can not be empty", e.getLocalizedMessage());
-    }
   }
 
   /**

hbase-client/src/test/java/org/apache/hadoop/hbase/client/TestDelayingRunner.java

@@ -19,6 +19,7 @@ package org.apache.hadoop.hbase.client;
 
 import static org.junit.Assert.*;
 
+import java.nio.charset.StandardCharsets;
 import java.util.concurrent.atomic.AtomicLong;
 
 import org.apache.hadoop.hbase.HRegionInfo;
@@ -33,8 +34,8 @@ public class TestDelayingRunner {
 
   private static final TableName DUMMY_TABLE =
       TableName.valueOf("DUMMY_TABLE");
-  private static final byte[] DUMMY_BYTES_1 = "DUMMY_BYTES_1".getBytes();
+  private static final byte[] DUMMY_BYTES_1 = "DUMMY_BYTES_1".getBytes(StandardCharsets.UTF_8);
-  private static final byte[] DUMMY_BYTES_2 = "DUMMY_BYTES_2".getBytes();
+  private static final byte[] DUMMY_BYTES_2 = "DUMMY_BYTES_2".getBytes(StandardCharsets.UTF_8);
   private static HRegionInfo hri1 =
       new HRegionInfo(DUMMY_TABLE, DUMMY_BYTES_1, DUMMY_BYTES_2, false, 1);
 

hbase-client/src/test/java/org/apache/hadoop/hbase/client/TestOperation.java

@@ -23,6 +23,7 @@ import static org.junit.Assert.assertNotNull;
 
 import java.io.IOException;
 import java.nio.ByteBuffer;
+import java.nio.charset.StandardCharsets;
 import java.util.Arrays;
 import java.util.HashMap;
 import java.util.List;
@@ -94,13 +95,14 @@ public class TestOperation {
 
   private static String COL_NAME_1 = "col1";
   private static ColumnPrefixFilter COL_PRE_FILTER =
-      new ColumnPrefixFilter(COL_NAME_1.getBytes());
+      new ColumnPrefixFilter(COL_NAME_1.getBytes(StandardCharsets.UTF_8));
   private static String STR_COL_PRE_FILTER =
       COL_PRE_FILTER.getClass().getSimpleName() + " " + COL_NAME_1;
 
   private static String COL_NAME_2 = "col2";
   private static ColumnRangeFilter CR_FILTER = new ColumnRangeFilter(
-      COL_NAME_1.getBytes(), true, COL_NAME_2.getBytes(), false);
+      COL_NAME_1.getBytes(StandardCharsets.UTF_8), true,
+      COL_NAME_2.getBytes(StandardCharsets.UTF_8), false);
   private static String STR_CR_FILTER = CR_FILTER.getClass().getSimpleName()
       + " [" + COL_NAME_1 + ", " + COL_NAME_2 + ")";
 
@@ -119,25 +121,28 @@ public class TestOperation {
 
   private static String STOP_ROW_KEY = "stop";
   private static InclusiveStopFilter IS_FILTER =
-      new InclusiveStopFilter(STOP_ROW_KEY.getBytes());
+      new InclusiveStopFilter(STOP_ROW_KEY.getBytes(StandardCharsets.UTF_8));
   private static String STR_IS_FILTER =
       IS_FILTER.getClass().getSimpleName() + " " + STOP_ROW_KEY;
 
   private static String PREFIX = "prefix";
   private static PrefixFilter PREFIX_FILTER =
-      new PrefixFilter(PREFIX.getBytes());
+      new PrefixFilter(PREFIX.getBytes(StandardCharsets.UTF_8));
   private static String STR_PREFIX_FILTER = "PrefixFilter " + PREFIX;
 
   private static byte[][] PREFIXES = {
-      "0".getBytes(), "1".getBytes(), "2".getBytes()};
+      "0".getBytes(StandardCharsets.UTF_8), "1".getBytes(StandardCharsets.UTF_8),
+      "2".getBytes(StandardCharsets.UTF_8)};
   private static MultipleColumnPrefixFilter MCP_FILTER =
       new MultipleColumnPrefixFilter(PREFIXES);
   private static String STR_MCP_FILTER =
       MCP_FILTER.getClass().getSimpleName() + " (3/3): [0, 1, 2]";
 
   private static byte[][] L_PREFIXES = {
-    "0".getBytes(), "1".getBytes(), "2".getBytes(), "3".getBytes(),
+    "0".getBytes(StandardCharsets.UTF_8), "1".getBytes(StandardCharsets.UTF_8),
-    "4".getBytes(), "5".getBytes(), "6".getBytes(), "7".getBytes()};
+    "2".getBytes(StandardCharsets.UTF_8), "3".getBytes(StandardCharsets.UTF_8),
+    "4".getBytes(StandardCharsets.UTF_8), "5".getBytes(StandardCharsets.UTF_8),
+    "6".getBytes(StandardCharsets.UTF_8), "7".getBytes(StandardCharsets.UTF_8)};
   private static MultipleColumnPrefixFilter L_MCP_FILTER =
       new MultipleColumnPrefixFilter(L_PREFIXES);
   private static String STR_L_MCP_FILTER =
@@ -167,7 +172,7 @@ public class TestOperation {
       FIRST_KEY_ONLY_FILTER.getClass().getSimpleName();
 
   private static CompareOp CMP_OP = CompareOp.EQUAL;
-  private static byte[] CMP_VALUE = "value".getBytes();
+  private static byte[] CMP_VALUE = "value".getBytes(StandardCharsets.UTF_8);
   private static BinaryComparator BC = new BinaryComparator(CMP_VALUE);
   private static DependentColumnFilter DC_FILTER =
       new DependentColumnFilter(FAMILY, QUALIFIER, true, CMP_OP, BC);
@@ -451,4 +456,3 @@ public class TestOperation {
   }
 
 }
-

hbase-client/src/test/java/org/apache/hadoop/hbase/client/TestRegionInfoDisplay.java

@@ -17,6 +17,9 @@
  */
 package org.apache.hadoop.hbase.client;
 
+import java.io.IOException;
+import java.nio.charset.StandardCharsets;
+
 import org.apache.hadoop.conf.Configuration;
 import org.apache.hadoop.hbase.CategoryBasedTimeout;
 import org.apache.hadoop.hbase.HRegionInfo;
@@ -32,13 +35,11 @@ import org.junit.experimental.categories.Category;
 import org.junit.rules.TestName;
 import org.junit.rules.TestRule;
 
-import java.io.IOException;
-
 @Category({MasterTests.class, SmallTests.class})
 public class TestRegionInfoDisplay {
   @Rule
-  public final TestRule timeout = CategoryBasedTimeout.builder().withTimeout(this.getClass()).
+  public final TestRule timeout = CategoryBasedTimeout.builder()
-  withLookingForStuckThread(true).build();
+      .withTimeout(this.getClass()).withLookingForStuckThread(true).build();
   @Rule public TestName name = new TestName();
 
   @Test
@@ -79,12 +80,13 @@ public class TestRegionInfoDisplay {
       byte[] startKey) {
     // except for the "hidden-start-key" substring everything else should exactly match
     String firstPart = descriptiveNameForDisplay.substring(0,
-    descriptiveNameForDisplay.indexOf(new String(RegionInfoDisplay.HIDDEN_START_KEY)));
+        descriptiveNameForDisplay.indexOf(
+        new String(RegionInfoDisplay.HIDDEN_START_KEY, StandardCharsets.UTF_8)));
     String secondPart = descriptiveNameForDisplay.substring(
-    descriptiveNameForDisplay.indexOf(new String(RegionInfoDisplay.HIDDEN_START_KEY)) +
+        descriptiveNameForDisplay.indexOf(
+        new String(RegionInfoDisplay.HIDDEN_START_KEY, StandardCharsets.UTF_8)) +
             RegionInfoDisplay.HIDDEN_START_KEY.length);
-    String firstPartOrig = origDesc.substring(0,
+    String firstPartOrig = origDesc.substring(0, origDesc.indexOf(Bytes.toStringBinary(startKey)));
-    origDesc.indexOf(Bytes.toStringBinary(startKey)));
     String secondPartOrig = origDesc.substring(
         origDesc.indexOf(Bytes.toStringBinary(startKey)) +
             Bytes.toStringBinary(startKey).length());
@@ -118,8 +120,8 @@ public class TestRegionInfoDisplay {
   }
 
   private HRegionInfo convert(RegionInfo ri) {
-    HRegionInfo hri = new HRegionInfo(
+    HRegionInfo hri =new HRegionInfo(ri.getTable(), ri.getStartKey(), ri.getEndKey(),
-    ri.getTable(), ri.getStartKey(), ri.getEndKey(), ri.isSplit(), ri.getRegionId());
+        ri.isSplit(), ri.getRegionId());
     hri.setOffline(ri.isOffline());
     return hri;
   }

hbase-client/src/test/java/org/apache/hadoop/hbase/client/TestSimpleRequestController.java

@@ -1,5 +1,4 @@
 /*
- *
  * Licensed to the Apache Software Foundation (ASF) under one
  * or more contributor license agreements.  See the NOTICE file
  * distributed with this work for additional information
@@ -18,8 +17,14 @@
  */
 package org.apache.hadoop.hbase.client;
 
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertNotEquals;
+import static org.junit.Assert.assertTrue;
+import static org.junit.Assert.fail;
+
 import java.io.IOException;
 import java.io.InterruptedIOException;
+import java.nio.charset.StandardCharsets;
 import java.util.Arrays;
 import java.util.HashMap;
 import java.util.Map;
@@ -27,6 +32,7 @@ import java.util.concurrent.BrokenBarrierException;
 import java.util.concurrent.CyclicBarrier;
 import java.util.concurrent.atomic.AtomicInteger;
 import java.util.concurrent.atomic.AtomicLong;
+
 import org.apache.hadoop.conf.Configuration;
 import org.apache.hadoop.hbase.HBaseConfiguration;
 import org.apache.hadoop.hbase.HConstants;
@@ -39,10 +45,6 @@ import org.apache.hadoop.hbase.testclassification.ClientTests;
 import org.apache.hadoop.hbase.testclassification.SmallTests;
 import org.apache.hadoop.hbase.util.Bytes;
 import org.junit.Assert;
-import static org.junit.Assert.assertEquals;
-import static org.junit.Assert.assertNotEquals;
-import static org.junit.Assert.assertTrue;
-import static org.junit.Assert.fail;
 import org.junit.Test;
 import org.junit.experimental.categories.Category;
 
@@ -51,9 +53,9 @@ public class TestSimpleRequestController {
 
   private static final TableName DUMMY_TABLE
           = TableName.valueOf("DUMMY_TABLE");
-  private static final byte[] DUMMY_BYTES_1 = "DUMMY_BYTES_1".getBytes();
+  private static final byte[] DUMMY_BYTES_1 = "DUMMY_BYTES_1".getBytes(StandardCharsets.UTF_8);
-  private static final byte[] DUMMY_BYTES_2 = "DUMMY_BYTES_2".getBytes();
+  private static final byte[] DUMMY_BYTES_2 = "DUMMY_BYTES_2".getBytes(StandardCharsets.UTF_8);
-  private static final byte[] DUMMY_BYTES_3 = "DUMMY_BYTES_3".getBytes();
+  private static final byte[] DUMMY_BYTES_3 = "DUMMY_BYTES_3".getBytes(StandardCharsets.UTF_8);
   private static final ServerName SN = ServerName.valueOf("s1,1,1");
   private static final ServerName SN2 = ServerName.valueOf("s2,2,2");
   private static final HRegionInfo HRI1
@@ -118,15 +120,18 @@ public class TestSimpleRequestController {
     final AtomicLong tasksInProgress = new AtomicLong(0);
     final Map<ServerName, AtomicInteger> taskCounterPerServer = new HashMap<>();
     final Map<byte[], AtomicInteger> taskCounterPerRegion = new HashMap<>();
-    SimpleRequestController.TaskCountChecker countChecker = new SimpleRequestController.TaskCountChecker(
+    SimpleRequestController.TaskCountChecker countChecker =
+        new SimpleRequestController.TaskCountChecker(
             maxTotalConcurrentTasks,
             maxConcurrentTasksPerServer,
             maxConcurrentTasksPerRegion,
             tasksInProgress, taskCounterPerServer, taskCounterPerRegion);
     final long maxHeapSizePerRequest = 2 * 1024 * 1024;
     // unlimiited
-    SimpleRequestController.RequestHeapSizeChecker sizeChecker = new SimpleRequestController.RequestHeapSizeChecker(maxHeapSizePerRequest);
+    SimpleRequestController.RequestHeapSizeChecker sizeChecker =
-    RequestController.Checker checker = SimpleRequestController.newChecker(Arrays.asList(countChecker, sizeChecker));
+        new SimpleRequestController.RequestHeapSizeChecker(maxHeapSizePerRequest);
+    RequestController.Checker checker =
+        SimpleRequestController.newChecker(Arrays.asList(countChecker, sizeChecker));
     ReturnCode loc1Code = checker.canTakeRow(LOC1, createPut(maxHeapSizePerRequest));
     assertEquals(ReturnCode.INCLUDE, loc1Code);
 
@@ -357,11 +362,7 @@ public class TestSimpleRequestController {
         controller.waitForMaximumCurrentTasks(max.get(), 123, 1, null);
       } catch (InterruptedIOException e) {
         Assert.fail(e.getMessage());
-      } catch (InterruptedException e) {
+      } catch (InterruptedException | BrokenBarrierException e) {
-        // TODO Auto-generated catch block
-        e.printStackTrace();
-      } catch (BrokenBarrierException e) {
-        // TODO Auto-generated catch block
         e.printStackTrace();
       }
     };

hbase-client/src/test/java/org/apache/hadoop/hbase/client/TestSnapshotFromAdmin.java

@@ -71,7 +71,7 @@ public class TestSnapshotFromAdmin {
       ignoreExpectedTime += HConstants.RETRY_BACKOFF[i] * pauseTime;
     }
     // the correct wait time, capping at the maxTime/tries + fudge room
-    final long time = pauseTime * 3 + ((maxWaitTime / numRetries) * 3) + 300;
+    final long time = pauseTime * 3L + ((maxWaitTime / numRetries) * 3) + 300L;
     assertTrue("Capped snapshot wait time isn't less that the uncapped backoff time "
         + "- further testing won't prove anything.", time < ignoreExpectedTime);
 

hbase-client/src/test/java/org/apache/hadoop/hbase/client/TestTableDescriptorBuilder.java

@@ -113,7 +113,7 @@ public class TestTableDescriptorBuilder {
     assertEquals(v, deserializedHtd.getMaxFileSize());
     assertTrue(deserializedHtd.isReadOnly());
     assertEquals(Durability.ASYNC_WAL, deserializedHtd.getDurability());
-    assertEquals(deserializedHtd.getRegionReplication(), 2);
+    assertEquals(2, deserializedHtd.getRegionReplication());
   }
 
   /**

hbase-client/src/test/java/org/apache/hadoop/hbase/security/TestHBaseSaslRpcClient.java

@@ -30,8 +30,7 @@ import static org.mockito.Mockito.when;
 import org.apache.hadoop.hbase.shaded.com.google.common.base.Strings;
 
 import java.io.IOException;
-import java.io.InputStream;
+import java.nio.charset.StandardCharsets;
-import java.io.OutputStream;
 
 import javax.security.auth.callback.Callback;
 import javax.security.auth.callback.CallbackHandler;
@@ -100,8 +99,10 @@ public class TestHBaseSaslRpcClient {
   @Test
   public void testSaslClientCallbackHandler() throws UnsupportedCallbackException {
     final Token<? extends TokenIdentifier> token = createTokenMock();
-    when(token.getIdentifier()).thenReturn(DEFAULT_USER_NAME.getBytes());
+    when(token.getIdentifier())
-    when(token.getPassword()).thenReturn(DEFAULT_USER_PASSWORD.getBytes());
+      .thenReturn(DEFAULT_USER_NAME.getBytes(StandardCharsets.UTF_8));
+    when(token.getPassword())
+      .thenReturn(DEFAULT_USER_PASSWORD.getBytes(StandardCharsets.UTF_8));
 
     final NameCallback nameCallback = mock(NameCallback.class);
     final PasswordCallback passwordCallback = mock(PasswordCallback.class);
@@ -120,8 +121,10 @@ public class TestHBaseSaslRpcClient {
   @Test
   public void testSaslClientCallbackHandlerWithException() {
     final Token<? extends TokenIdentifier> token = createTokenMock();
-    when(token.getIdentifier()).thenReturn(DEFAULT_USER_NAME.getBytes());
+    when(token.getIdentifier())
-    when(token.getPassword()).thenReturn(DEFAULT_USER_PASSWORD.getBytes());
+      .thenReturn(DEFAULT_USER_NAME.getBytes(StandardCharsets.UTF_8));
+    when(token.getPassword())
+      .thenReturn(DEFAULT_USER_PASSWORD.getBytes(StandardCharsets.UTF_8));
     final SaslClientCallbackHandler saslClCallbackHandler = new SaslClientCallbackHandler(token);
     try {
       saslClCallbackHandler.handle(new Callback[] { mock(TextOutputCallback.class) });
@@ -291,8 +294,10 @@ public class TestHBaseSaslRpcClient {
       throws IOException {
     Token<? extends TokenIdentifier> token = createTokenMock();
     if (!Strings.isNullOrEmpty(principal) && !Strings.isNullOrEmpty(password)) {
-      when(token.getIdentifier()).thenReturn(DEFAULT_USER_NAME.getBytes());
+      when(token.getIdentifier())
-      when(token.getPassword()).thenReturn(DEFAULT_USER_PASSWORD.getBytes());
+        .thenReturn(DEFAULT_USER_NAME.getBytes(StandardCharsets.UTF_8));
+      when(token.getPassword())
+        .thenReturn(DEFAULT_USER_PASSWORD.getBytes(StandardCharsets.UTF_8));
     }
     return token;
   }

hbase-client/src/test/java/org/apache/hadoop/hbase/security/TestSaslUtil.java

@@ -40,20 +40,20 @@ public class TestSaslUtil {
     Map<String, String> props;
 
     props = SaslUtil.initSaslProperties("integrity");
-    assertEquals(props.get(Sasl.QOP), "auth-int");
+    assertEquals("auth-int", props.get(Sasl.QOP));
 
     props = SaslUtil.initSaslProperties("privacy,authentication");
-    assertEquals(props.get(Sasl.QOP), "auth-conf,auth");
+    assertEquals("auth-conf,auth", props.get(Sasl.QOP));
 
     props = SaslUtil.initSaslProperties("integrity,authentication,privacy");
-    assertEquals(props.get(Sasl.QOP), "auth-int,auth,auth-conf");
+    assertEquals("auth-int,auth,auth-conf", props.get(Sasl.QOP));
 
     exception.expect(IllegalArgumentException.class);
     props = SaslUtil.initSaslProperties("xyz");
-    assertEquals(props.get(Sasl.QOP), "auth");
+    assertEquals("auth", props.get(Sasl.QOP));
 
     exception.expect(IllegalArgumentException.class);
     props = SaslUtil.initSaslProperties("");
-    assertEquals(props.get(Sasl.QOP), "auth");
+    assertEquals("auth", props.get(Sasl.QOP));
   }
 }

hbase-common/src/main/java/org/apache/hadoop/hbase/ServerName.java

@@ -322,10 +322,27 @@ public class ServerName implements Comparable<ServerName>, Serializable {
 
   @Override
   public int compareTo(ServerName other) {
-    int compare = this.getHostname().compareToIgnoreCase(other.getHostname());
+    int compare;
-    if (compare != 0) return compare;
+    if (other == null) {
+      return -1;
+    }
+    if (this.getHostname() == null) {
+      if (other.getHostname() != null) {
+        return 1;
+      }
+    } else {
+      if (other.getHostname() == null) {
+        return -1;
+      }
+      compare = this.getHostname().compareToIgnoreCase(other.getHostname());
+      if (compare != 0) {
+        return compare;
+      }
+    }
     compare = this.getPort() - other.getPort();
-    if (compare != 0) return compare;
+    if (compare != 0) {
+      return compare;
+    }
     return Long.compare(this.getStartcode(), other.getStartcode());
   }
 

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

@@ -101,6 +101,7 @@ public class ReplicationTrackerZKImpl extends ReplicationStateZKBase implements
      * Called when a new node has been created.
      * @param path full path of the new node
      */
+    @Override
     public void nodeCreated(String path) {
       refreshListIfRightPath(path);
     }
@@ -109,6 +110,7 @@ public class ReplicationTrackerZKImpl extends ReplicationStateZKBase implements
      * Called when a node has been deleted
      * @param path full path of the deleted node
      */
+    @Override
     public void nodeDeleted(String path) {
       if (stopper.isStopped()) {
         return;
@@ -127,6 +129,7 @@ public class ReplicationTrackerZKImpl extends ReplicationStateZKBase implements
      * Called when an existing node has a child node added or removed.
      * @param path full path of the node whose children have changed
      */
+    @Override
     public void nodeChildrenChanged(String path) {
       if (stopper.isStopped()) {
         return;
@@ -158,6 +161,7 @@ public class ReplicationTrackerZKImpl extends ReplicationStateZKBase implements
      * Called when a node has been deleted
      * @param path full path of the deleted node
      */
+    @Override
     public void nodeDeleted(String path) {
       List<String> peers = refreshPeersList(path);
       if (peers == null) {
@@ -176,6 +180,7 @@ public class ReplicationTrackerZKImpl extends ReplicationStateZKBase implements
      * Called when an existing node has a child node added or removed.
      * @param path full path of the node whose children have changed
      */
+    @Override
     public void nodeChildrenChanged(String path) {
       List<String> peers = refreshPeersList(path);
       if (peers == null) {

hbase-server/src/main/java/org/apache/hadoop/hbase/filter/FilterWrapper.java

@@ -51,6 +51,7 @@ final public class FilterWrapper extends Filter {
   /**
    * @return The filter serialized using pb
    */
+  @Override
   public byte[] toByteArray() throws IOException {
     FilterProtos.FilterWrapper.Builder builder =
       FilterProtos.FilterWrapper.newBuilder();
@@ -170,6 +171,7 @@ final public class FilterWrapper extends Filter {
    * @return true if and only if the fields of the filter that are serialized
    * are equal to the corresponding fields in other.  Used for testing.
    */
+  @Override
   boolean areSerializedFieldsEqual(Filter o) {
     if (o == this) return true;
     if (!(o instanceof FilterWrapper)) return false;

hbase-zookeeper/src/main/java/org/apache/hadoop/hbase/zookeeper/EmptyWatcher.java

@@ -30,5 +30,6 @@ public class EmptyWatcher implements Watcher {
   public static final EmptyWatcher instance = new EmptyWatcher();
   private EmptyWatcher() {}
 
+  @Override
   public void process(WatchedEvent event) {}
 }

hbase-zookeeper/src/main/java/org/apache/hadoop/hbase/zookeeper/HQuorumPeer.java

@@ -24,6 +24,7 @@ import java.io.PrintWriter;
 import java.net.InetAddress;
 import java.net.NetworkInterface;
 import java.net.UnknownHostException;
+import java.nio.charset.StandardCharsets;
 import java.util.ArrayList;
 import java.util.Enumeration;
 import java.util.List;
@@ -155,7 +156,7 @@ public class HQuorumPeer {
     }
 
     File myIdFile = new File(dataDir, "myid");
-    PrintWriter w = new PrintWriter(myIdFile);
+    PrintWriter w = new PrintWriter(myIdFile, StandardCharsets.UTF_8.name());
     w.println(myId);
     w.close();
   }

hbase-zookeeper/src/main/java/org/apache/hadoop/hbase/zookeeper/ZKLeaderManager.java

@@ -43,6 +43,7 @@ import org.apache.zookeeper.KeeperException;
 public class ZKLeaderManager extends ZKListener {
   private static final Log LOG = LogFactory.getLog(ZKLeaderManager.class);
 
+  private final Object lock = new Object();
   private final AtomicBoolean leaderExists = new AtomicBoolean();
   private String leaderZNode;
   private byte[] nodeId;
@@ -85,14 +86,14 @@ public class ZKLeaderManager extends ZKListener {
 
   private void handleLeaderChange() {
     try {
-      synchronized(leaderExists) {
+      synchronized(lock) {
         if (ZKUtil.watchAndCheckExists(watcher, leaderZNode)) {
           LOG.info("Found new leader for znode: "+leaderZNode);
           leaderExists.set(true);
         } else {
           LOG.info("Leader change, but no new leader found");
           leaderExists.set(false);
-          leaderExists.notifyAll();
+          lock.notifyAll();
         }
       }
     } catch (KeeperException ke) {
@@ -136,10 +137,10 @@ public class ZKLeaderManager extends ZKListener {
       }
 
       // wait for next chance
-      synchronized(leaderExists) {
+      synchronized(lock) {
         while (leaderExists.get() && !candidate.isStopped()) {
           try {
-            leaderExists.wait();
+            lock.wait();
           } catch (InterruptedException ie) {
             LOG.debug("Interrupted waiting on leader", ie);
           }
@@ -153,7 +154,7 @@ public class ZKLeaderManager extends ZKListener {
    */
   public void stepDownAsLeader() {
     try {
-      synchronized(leaderExists) {
+      synchronized(lock) {
         if (!leaderExists.get()) {
           return;
         }

hbase-zookeeper/src/main/java/org/apache/hadoop/hbase/zookeeper/ZKUtil.java

@@ -19,11 +19,14 @@
 package org.apache.hadoop.hbase.zookeeper;
 
 import java.io.BufferedReader;
+import java.io.BufferedWriter;
 import java.io.IOException;
 import java.io.InputStreamReader;
+import java.io.OutputStreamWriter;
 import java.io.PrintWriter;
 import java.net.InetSocketAddress;
 import java.net.Socket;
+import java.nio.charset.StandardCharsets;
 import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.Deque;
@@ -1904,8 +1907,10 @@ public class ZKUtil {
       socket.connect(sockAddr, timeout);
 
       socket.setSoTimeout(timeout);
-      try (PrintWriter out = new PrintWriter(socket.getOutputStream(), true);
+      try (PrintWriter out = new PrintWriter(new BufferedWriter(
-          BufferedReader in = new BufferedReader(new InputStreamReader(socket.getInputStream()))) {
+          new OutputStreamWriter(socket.getOutputStream(), StandardCharsets.UTF_8)), true);
+          BufferedReader in = new BufferedReader(
+              new InputStreamReader(socket.getInputStream(), StandardCharsets.UTF_8))) {
         out.println("stat");
         out.flush();
         ArrayList<String> res = new ArrayList<>();

hbase-zookeeper/src/test/java/org/apache/hadoop/hbase/zookeeper/TestZKUtil.java

@@ -48,7 +48,7 @@ public class TestZKUtil {
     String node = "/hbase/testUnsecure";
     ZKWatcher watcher = new ZKWatcher(conf, node, null, false);
     List<ACL> aclList = ZKUtil.createACL(watcher, node, false);
-    Assert.assertEquals(aclList.size(), 1);
+    Assert.assertEquals(1, aclList.size());
     Assert.assertTrue(aclList.contains(Ids.OPEN_ACL_UNSAFE.iterator().next()));
   }
 
@@ -59,7 +59,7 @@ public class TestZKUtil {
     String node = "/hbase/testSecuritySingleSuperuser";
     ZKWatcher watcher = new ZKWatcher(conf, node, null, false);
     List<ACL> aclList = ZKUtil.createACL(watcher, node, true);
-    Assert.assertEquals(aclList.size(), 2); // 1+1, since ACL will be set for the creator by default
+    Assert.assertEquals(2, aclList.size()); // 1+1, since ACL will be set for the creator by default
     Assert.assertTrue(aclList.contains(new ACL(Perms.ALL, new Id("sasl", "user1"))));
     Assert.assertTrue(aclList.contains(Ids.CREATOR_ALL_ACL.iterator().next()));
   }
@@ -71,7 +71,7 @@ public class TestZKUtil {
     String node = "/hbase/testCreateACL";
     ZKWatcher watcher = new ZKWatcher(conf, node, null, false);
     List<ACL> aclList = ZKUtil.createACL(watcher, node, true);
-    Assert.assertEquals(aclList.size(), 4); // 3+1, since ACL will be set for the creator by default
+    Assert.assertEquals(4, aclList.size()); // 3+1, since ACL will be set for the creator by default
     Assert.assertFalse(aclList.contains(new ACL(Perms.ALL, new Id("sasl", "@group1"))));
     Assert.assertFalse(aclList.contains(new ACL(Perms.ALL, new Id("sasl", "@group2"))));
     Assert.assertTrue(aclList.contains(new ACL(Perms.ALL, new Id("sasl", "user1"))));
@@ -87,7 +87,7 @@ public class TestZKUtil {
     String node = "/hbase/testCreateACL";
     ZKWatcher watcher = new ZKWatcher(conf, node, null, false);
     List<ACL> aclList = ZKUtil.createACL(watcher, node, true);
-    Assert.assertEquals(aclList.size(), 3); // 3, since service user the same as one of superuser
+    Assert.assertEquals(3, aclList.size()); // 3, since service user the same as one of superuser
     Assert.assertFalse(aclList.contains(new ACL(Perms.ALL, new Id("sasl", "@group1"))));
     Assert.assertTrue(aclList.contains(new ACL(Perms.ALL, new Id("auth", ""))));
     Assert.assertTrue(aclList.contains(new ACL(Perms.ALL, new Id("sasl", "user5"))));