HDFS-9174. Fix findbugs warnings in FSOutputSummer.tracer and DirectoryScanner$ReportCompiler.currentThread. Contributed by Yi Liu.

hadoop-common-project/hadoop-common/src/main/java/org/apache/hadoop/fs/FSOutputSummer.java

@@ -22,7 +22,6 @@ import org.apache.hadoop.classification.InterfaceAudience;
 import org.apache.hadoop.classification.InterfaceStability;
 import org.apache.hadoop.util.DataChecksum;
 import org.apache.htrace.core.TraceScope;
-import org.apache.htrace.core.Tracer;
 
 import java.io.IOException;
 import java.io.OutputStream;
@@ -43,8 +42,6 @@ abstract public class FSOutputSummer extends OutputStream {
   private byte checksum[];
   // The number of valid bytes in the buffer.
   private int count;
-  // The HTrace tracer to use
-  private Tracer tracer;
   
   // We want this value to be a multiple of 3 because the native code checksums
   // 3 chunks simultaneously. The chosen value of 9 strikes a balance between

hadoop-hdfs-project/hadoop-hdfs/CHANGES.txt

@@ -1115,6 +1115,9 @@ Release 2.8.0 - UNRELEASED
     HDFS-9141. Thread leak in Datanode#refreshVolumes. (Uma Maheswara Rao G
     via yliu)
 
+    HDFS-9174. Fix findbugs warnings in FSOutputSummer.tracer and
+    DirectoryScanner$ReportCompiler.currentThread. (Yi Liu via wheat9)
+
 Release 2.7.2 - UNRELEASED
 
   INCOMPATIBLE CHANGES

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/datanode/DirectoryScanner.java

@@ -784,12 +784,6 @@ public class DirectoryScanner implements Runnable {
     // purposes
     private final StopWatch perfTimer = new StopWatch();
 
-    /**
-     * The associated thread.  Used for testing purposes only.
-     */
-    @VisibleForTesting
-    Thread currentThread;
-
     /**
      * Create a report compiler for the given volume on the given datanode.
      *
@@ -809,8 +803,6 @@ public class DirectoryScanner implements Runnable {
      */
     @Override
     public ScanInfoPerBlockPool call() throws IOException {
-      currentThread = Thread.currentThread();
-
       String[] bpList = volume.getBlockPoolList();
       ScanInfoPerBlockPool result = new ScanInfoPerBlockPool(bpList.length);
       for (String bpid : bpList) {