HBASE-18308 Eliminate the findbugs warnings for hbase-server

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

@@ -309,14 +309,12 @@ public class LocalHBaseCluster {
    */
   public HMaster getActiveMaster() {
     for (JVMClusterUtil.MasterThread mt : masterThreads) {
-      if (mt.getMaster().isActiveMaster()) {
       // Ensure that the current active master is not stopped.
       // We don't want to return a stopping master as an active master.
       if (mt.getMaster().isActiveMaster()  && !mt.getMaster().isStopped()) {
         return mt.getMaster();
       }
     }
-    }
     return null;
   }
 

hbase-server/src/main/java/org/apache/hadoop/hbase/constraint/Constraints.java

@@ -614,8 +614,8 @@ public final class Constraints {
     @Override
     public int compare(Constraint c1, Constraint c2) {
       // compare the priorities of the constraints stored in their configuration
-      return Long.valueOf(c1.getConf().getLong(PRIORITY_KEY, DEFAULT_PRIORITY))
+      return Long.compare(c1.getConf().getLong(PRIORITY_KEY, DEFAULT_PRIORITY),
-          .compareTo(c2.getConf().getLong(PRIORITY_KEY, DEFAULT_PRIORITY));
+          c2.getConf().getLong(PRIORITY_KEY, DEFAULT_PRIORITY));
     }
   };
 

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

@@ -50,6 +50,7 @@ import org.apache.hadoop.hbase.regionserver.handler.WALSplitterHandler;
 import org.apache.hadoop.hbase.util.CancelableProgressable;
 import org.apache.hadoop.hbase.util.EnvironmentEdgeManager;
 import org.apache.hadoop.hbase.wal.AbstractFSWALProvider;
+import org.apache.hadoop.hbase.zookeeper.RecoverableZooKeeper;
 import org.apache.hadoop.hbase.zookeeper.ZKSplitLog;
 import org.apache.hadoop.hbase.zookeeper.ZKUtil;
 import org.apache.hadoop.hbase.zookeeper.ZooKeeperListener;
@@ -572,7 +573,7 @@ public class ZkSplitLogWorkerCoordination extends ZooKeeperListener implements
         getDataSetWatchFailure(path);
         return;
       }
-      data = watcher.getRecoverableZooKeeper().removeMetaData(data);
+      data = RecoverableZooKeeper.removeMetaData(data);
       getDataSetWatchSuccess(path, data);
     }
   }

hbase-server/src/main/java/org/apache/hadoop/hbase/mapreduce/JarFinder.java

@@ -90,6 +90,9 @@ public class JarFinder {
   private static void zipDir(File dir, String relativePath, ZipOutputStream zos,
                              boolean start) throws IOException {
     String[] dirList = dir.list();
+    if (dirList == null) {
+      return;
+    }
     for (String aDirList : dirList) {
       File f = new File(dir, aDirList);
       if (!f.isHidden()) {

hbase-server/src/main/java/org/apache/hadoop/hbase/mapreduce/LoadIncrementalHFiles.java

@@ -1026,12 +1026,6 @@ public class LoadIncrementalHFiles extends Configured implements Tool {
   protected List<LoadQueueItem> tryAtomicRegionLoad(ClientServiceCallable<byte[]> serviceCallable,
       final TableName tableName, final byte[] first, final Collection<LoadQueueItem> lqis)
       throws IOException {
-    final List<Pair<byte[], String>> famPaths = new ArrayList<>(lqis.size());
-    for (LoadQueueItem lqi : lqis) {
-      if (!unmatchedFamilies.contains(Bytes.toString(lqi.family))) {
-        famPaths.add(Pair.newPair(lqi.family, lqi.hfilePath.toString()));
-      }
-    }
     try {
       List<LoadQueueItem> toRetry = new ArrayList<>();
       Configuration conf = getConf();

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

@@ -134,11 +134,6 @@ public class DeadServer {
 
     assert numProcessing >= 0: "Number of dead servers in processing should always be non-negative";
 
-    if (numProcessing < 0) {
-      LOG.error("Number of dead servers in processing = " + numProcessing
-          + ". Something went wrong, this should always be non-negative.");
-      numProcessing = 0;
-    }
     if (numProcessing == 0) { processing = false; }
   }
 

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

@@ -2858,7 +2858,6 @@ public class HRegion implements HeapSize, PropagatingConfigurationObserver, Regi
     checkResources();
     startRegionOperation(Operation.DELETE);
     try {
-      delete.getRow();
       // All edits for the given row (across all column families) must happen atomically.
       doBatchMutate(delete);
     } finally {
@@ -3192,9 +3191,6 @@ public class HRegion implements HeapSize, PropagatingConfigurationObserver, Regi
    * In here we also handle replay of edits on region recover.
    * @return Change in size brought about by applying <code>batchOp</code>
    */
-  @edu.umd.cs.findbugs.annotations.SuppressWarnings(value="UL_UNRELEASED_LOCK",
-      justification="Findbugs seems to be confused on this.")
-  @SuppressWarnings("unchecked")
   // TODO: This needs a rewrite. Doesn't have to be this long. St.Ack 20160120
   private void doMiniBatchMutate(BatchOperation<?> batchOp) throws IOException {
     boolean replay = batchOp.isInReplay();

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

@@ -505,7 +505,7 @@ public class ReplicationSource extends Thread implements ReplicationSourceInterf
 
     @Override
     public int compare(Path o1, Path o2) {
-      return Long.valueOf(getTS(o1)).compareTo(getTS(o2));
+      return Long.compare(getTS(o1), getTS(o2));
     }
 
     /**

hbase-server/src/main/java/org/apache/hadoop/hbase/tool/Canary.java

@@ -1081,10 +1081,11 @@ public final class Canary implements Tool {
             }
           }
           Map<String, AtomicLong> actualReadTableLatency = regionSink.getReadLatencyMap();
-          for (String tableName : this.configuredReadTableTimeouts.keySet()) {
+          for (Map.Entry<String, Long> entry : configuredReadTableTimeouts.entrySet()) {
+            String tableName = entry.getKey();
             if (actualReadTableLatency.containsKey(tableName)) {
               Long actual = actualReadTableLatency.get(tableName).longValue();
-              Long configured = this.configuredReadTableTimeouts.get(tableName);
+              Long configured = entry.getValue();
               LOG.info("Read operation for " + tableName + " took " + actual +
                 " ms. The configured read timeout was " + configured + " ms.");
               if (actual > configured) {