MAPREDUCE-4138. Reduce memory usage of counters due to non-static nested classes.

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/trunk@1331023 13f79535-47bb-0310-9956-ffa450edef68

hadoop-mapreduce-project/CHANGES.txt

@@ -154,6 +154,9 @@ Release 2.0.0 - UNRELEASED
     MAPREDUCE-4093. Improve RM WebApp start up when proxy address is not set
     (Devaraj K vai bobby)
 
+    MAPREDUCE-4138. Reduce memory usage of counters due to non-static nested
+    classes. (tomwhite)
+
   OPTIMIZATIONS
 
   BUG FIXES

hadoop-mapreduce-project/hadoop-mapreduce-client/hadoop-mapreduce-client-core/src/main/java/org/apache/hadoop/mapred/Counters.java

@@ -387,21 +387,13 @@ public class Counters
   private static class FrameworkGroupImpl<T extends Enum<T>>
       extends FrameworkCounterGroup<T, Counter> {
 
-    // Mix the framework counter implementation into the Counter interface
-    class FrameworkCounterImpl extends FrameworkCounter {
-      FrameworkCounterImpl(T key) {
-        super(key);
-      }
-
-    }
-
     FrameworkGroupImpl(Class<T> cls) {
       super(cls);
     }
 
     @Override
     protected Counter newCounter(T key) {
-      return new Counter(new FrameworkCounterImpl(key));
+      return new Counter(new FrameworkCounter<T>(key, getName()));
     }
 
     @Override
@@ -413,17 +405,9 @@ public class Counters
   // Mix the file system counter group implementation into the Group interface
   private static class FSGroupImpl extends FileSystemCounterGroup<Counter> {
 
-    private class FSCounterImpl extends FSCounter {
-
-      FSCounterImpl(String scheme, FileSystemCounter key) {
-        super(scheme, key);
-      }
-
-    }
-
     @Override
     protected Counter newCounter(String scheme, FileSystemCounter key) {
-      return new Counter(new FSCounterImpl(scheme, key));
+      return new Counter(new FSCounter(scheme, key));
     }
 
     @Override

hadoop-mapreduce-project/hadoop-mapreduce-client/hadoop-mapreduce-client-core/src/main/java/org/apache/hadoop/mapreduce/Counters.java

@@ -49,8 +49,8 @@ public class Counters extends AbstractCounters<Counter, CounterGroup> {
     }
 
     @Override
-    protected FrameworkCounter newCounter(T key) {
+    protected FrameworkCounter<T> newCounter(T key) {
-      return new FrameworkCounter(key);
+      return new FrameworkCounter<T>(key, getName());
     }
 
     @Override

hadoop-mapreduce-project/hadoop-mapreduce-client/hadoop-mapreduce-client-core/src/main/java/org/apache/hadoop/mapreduce/counters/FileSystemCounterGroup.java

@@ -61,7 +61,7 @@ public abstract class FileSystemCounterGroup<C extends Counter>
   private static final Joiner DISP_JOINER = Joiner.on(": ");
 
   @InterfaceAudience.Private
-  public class FSCounter extends AbstractCounter {
+  public static class FSCounter extends AbstractCounter {
     final String scheme;
     final FileSystemCounter key;
     private long value;
@@ -139,8 +139,7 @@ public abstract class FileSystemCounterGroup<C extends Counter>
   @Override
   public void addCounter(C counter) {
     C ours;
-    if (counter instanceof FileSystemCounterGroup<?>.FSCounter) {
+    if (counter instanceof FileSystemCounterGroup.FSCounter) {
-      @SuppressWarnings("unchecked")
       FSCounter c = (FSCounter) counter;
       ours = findCounter(c.scheme, c.key);
     }

hadoop-mapreduce-project/hadoop-mapreduce-client/hadoop-mapreduce-client-core/src/main/java/org/apache/hadoop/mapreduce/counters/FrameworkCounterGroup.java

@@ -57,12 +57,14 @@ public abstract class FrameworkCounterGroup<T extends Enum<T>,
    * Use old (which extends new) interface to make compatibility easier.
    */
   @InterfaceAudience.Private
-  public class FrameworkCounter extends AbstractCounter {
+  public static class FrameworkCounter<T extends Enum<T>> extends AbstractCounter {
     final T key;
+    final String groupName;
     private long value;
 
-    public FrameworkCounter(T ref) {
+    public FrameworkCounter(T ref, String groupName) {
       key = ref;
+      this.groupName = groupName;
     }
 
     @Override
@@ -72,7 +74,7 @@ public abstract class FrameworkCounterGroup<T extends Enum<T>,
 
     @Override
     public String getDisplayName() {
-      return localizeCounterName(getName());
+      return ResourceBundles.getCounterName(groupName, getName(), getName());
     }
 
     @Override
@@ -131,10 +133,6 @@ public abstract class FrameworkCounterGroup<T extends Enum<T>,
     this.displayName = displayName;
   }
 
-    private String localizeCounterName(String counterName) {
-      return ResourceBundles.getCounterName(getName(), counterName, counterName);
-    }
-
   private T valueOf(String name) {
     return Enum.valueOf(enumClass, name);
   }
@@ -204,7 +202,7 @@ public abstract class FrameworkCounterGroup<T extends Enum<T>,
     if (checkNotNull(other, "other counter group")
         instanceof FrameworkCounterGroup<?, ?>) {
       for (Counter counter : other) {
-        findCounter(((FrameworkCounter) counter).key)
+        findCounter(((FrameworkCounter) counter).key.name())
             .increment(counter.getValue());
       }
     }