YARN-43. Fix TestResourceTrackerService to not depend on test order and thus pass on JDK7. Contributed by Thomas Graves.

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/trunk@1399066 13f79535-47bb-0310-9956-ffa450edef68

hadoop-yarn-project/CHANGES.txt

@@ -148,6 +148,9 @@ Release 0.23.5 - UNRELEASED
     YARN-161. Fix multiple compiler warnings for unchecked operations in YARN
     common. (Chris Nauroth via vinodkv)
 
+    YARN-43. Fix TestResourceTrackerService to not depend on test order and thus
+    pass on JDK7. (Thomas Graves via vinodkv)
+
   OPTIMIZATIONS
 
   BUG FIXES

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-resourcemanager/src/main/java/org/apache/hadoop/yarn/server/resourcemanager/ClusterMetrics.java

@@ -30,7 +30,7 @@
 import org.apache.hadoop.metrics2.lib.DefaultMetricsSystem;
 import org.apache.hadoop.metrics2.lib.MetricsRegistry;
 import org.apache.hadoop.metrics2.lib.MutableGaugeInt;
-import org.apache.hadoop.yarn.server.resourcemanager.rmnode.RMNodeEventType;
+import com.google.common.annotations.VisibleForTesting;
 
 @InterfaceAudience.Private
 @Metrics(context="yarn")
@@ -71,6 +71,12 @@ private static void registerMetrics() {
       ms.register("ClusterMetrics", "Metrics for the Yarn Cluster", INSTANCE);
     }
   }
+
+  @VisibleForTesting
+  synchronized static void destroy() {
+    isInitialized.set(false);
+    INSTANCE = null;
+  }
   
   //Active Nodemanagers
   public int getNumActiveNMs() {
@@ -136,4 +142,5 @@ public void incrNumActiveNodes() {
   public void decrNumActiveNodes() {
     numActiveNMs.decr();
   }
+
 }

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-resourcemanager/src/test/java/org/apache/hadoop/yarn/server/resourcemanager/TestResourceTrackerService.java

@@ -414,6 +414,7 @@ public void tearDown() {
     if (hostFile != null && hostFile.exists()) {
       hostFile.delete();
     }
+    ClusterMetrics.destroy();
     if (rm != null) {
       rm.stop();
     }