YARN-746. Renamed Service.register() and Service.unregister() to registerServiceListener() & unregisterServiceListener() respectively. Contributed by Steve Loughran.

svn merge --ignore-ancestry -c 1492780 ../../trunk/


git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-2@1492781 13f79535-47bb-0310-9956-ffa450edef68

hadoop-yarn-project/CHANGES.txt

@@ -116,6 +116,10 @@ Release 2.1.0-beta - UNRELEASED
     robust subclassing and migrated yarn-common services. (Steve Loughran via
     vinodkv)
 
+    YARN-746. Renamed Service.register() and Service.unregister() to
+    registerServiceListener() & unregisterServiceListener() respectively.
+    (Steve Loughran via vinodkv)
+
   NEW FEATURES
 
     YARN-482. FS: Extend SchedulingMode to intermediate queues. 

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-common/src/main/java/org/apache/hadoop/yarn/service/AbstractService.java

@@ -353,12 +353,12 @@ public abstract class AbstractService implements Service {
   }
 
   @Override
-  public void register(ServiceStateChangeListener l) {
+  public void registerServiceListener(ServiceStateChangeListener l) {
     listeners.add(l);
   }
 
   @Override
-  public void unregister(ServiceStateChangeListener l) {
+  public void unregisterServiceListener(ServiceStateChangeListener l) {
     listeners.remove(l);
   }
 

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-common/src/main/java/org/apache/hadoop/yarn/service/FilterService.java

@@ -54,13 +54,13 @@ public class FilterService implements Service {
   }
 
   @Override
-  public void register(ServiceStateChangeListener listener) {
+  public void registerServiceListener(ServiceStateChangeListener listener) {
-    service.register(listener);
+    service.registerServiceListener(listener);
   }
 
   @Override
-  public void unregister(ServiceStateChangeListener listener) {
+  public void unregisterServiceListener(ServiceStateChangeListener listener) {
-    service.unregister(listener);
+    service.unregisterServiceListener(listener);
   }
 
   @Override

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-common/src/main/java/org/apache/hadoop/yarn/service/Service.java

@@ -129,16 +129,19 @@ public interface Service extends Closeable {
   void close() throws IOException;
 
   /**
-   * Register an instance of the service state change events.
+   * Register a listener to the service state change events.
+   * If the supplied listener is already listening to this service,
+   * this method is a no-op.
    * @param listener a new listener
    */
-  void register(ServiceStateChangeListener listener);
+  void registerServiceListener(ServiceStateChangeListener listener);
 
   /**
-   * Unregister a previously instance of the service state change events.
+   * Unregister a previously registered listener of the service state
+   * change events. No-op if the listener is already unregistered.
    * @param listener the listener to unregister.
    */
-  void unregister(ServiceStateChangeListener listener);
+  void unregisterServiceListener(ServiceStateChangeListener listener);
 
   /**
    * Get the name of this service.

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-common/src/test/java/org/apache/hadoop/yarn/service/TestServiceLifecycle.java

@@ -186,7 +186,7 @@ public class TestServiceLifecycle extends ServiceAssert {
   @Test
   public void testStopFailingInitAndStop() throws Throwable {
     BreakableService svc = new BreakableService(true, false, true);
-    svc.register(new LoggingStateChangeListener());
+    svc.registerServiceListener(new LoggingStateChangeListener());
     try {
       svc.init(new Configuration());
       fail("Expected a failure, got " + svc);
@@ -220,7 +220,7 @@ public class TestServiceLifecycle extends ServiceAssert {
   public void testServiceNotifications() throws Throwable {
     BreakableService svc = new BreakableService(false, false, false);
     BreakableStateChangeListener listener = new BreakableStateChangeListener();
-    svc.register(listener);
+    svc.registerServiceListener(listener);
     svc.init(new Configuration());
     assertEventCount(listener, 1);
     svc.start();
@@ -239,10 +239,10 @@ public class TestServiceLifecycle extends ServiceAssert {
   public void testServiceNotificationsStopOnceUnregistered() throws Throwable {
     BreakableService svc = new BreakableService(false, false, false);
     BreakableStateChangeListener listener = new BreakableStateChangeListener();
-    svc.register(listener);
+    svc.registerServiceListener(listener);
     svc.init(new Configuration());
     assertEventCount(listener, 1);
-    svc.unregister(listener);
+    svc.unregisterServiceListener(listener);
     svc.start();
     assertEventCount(listener, 1);
     svc.stop();
@@ -267,12 +267,12 @@ public class TestServiceLifecycle extends ServiceAssert {
       new SelfUnregisteringBreakableStateChangeListener();
     BreakableStateChangeListener l2 =
       new BreakableStateChangeListener();
-    svc.register(listener);
+    svc.registerServiceListener(listener);
-    svc.register(l2);
+    svc.registerServiceListener(l2);
     svc.init(new Configuration());
     assertEventCount(listener, 1);
     assertEventCount(l2, 1);
-    svc.unregister(listener);
+    svc.unregisterServiceListener(listener);
     svc.start();
     assertEventCount(listener, 1);
     assertEventCount(l2, 2);
@@ -287,7 +287,7 @@ public class TestServiceLifecycle extends ServiceAssert {
     @Override
     public synchronized void stateChanged(Service service) {
       super.stateChanged(service);
-      service.unregister(this);
+      service.unregisterServiceListener(this);
     }
   }
 
@@ -301,7 +301,7 @@ public class TestServiceLifecycle extends ServiceAssert {
     BreakableService svc = new BreakableService(false, false, false);
     BreakableStateChangeListener listener = new BreakableStateChangeListener();
     listener.setFailingState(Service.STATE.STARTED);
-    svc.register(listener);
+    svc.registerServiceListener(listener);
     svc.init(new Configuration());
     assertEventCount(listener, 1);
     //start this; the listener failed but this won't show
@@ -326,7 +326,7 @@ public class TestServiceLifecycle extends ServiceAssert {
     //this tests that a listener can get notified when a service is stopped
     AsyncSelfTerminatingService service = new AsyncSelfTerminatingService(2000);
     NotifyingListener listener = new NotifyingListener();
-    service.register(listener);
+    service.registerServiceListener(listener);
     service.init(new Configuration());
     service.start();
     assertServiceInState(service, Service.STATE.STARTED);
@@ -344,7 +344,7 @@ public class TestServiceLifecycle extends ServiceAssert {
   public void testSelfTerminatingService() throws Throwable {
     SelfTerminatingService service = new SelfTerminatingService();
     BreakableStateChangeListener listener = new BreakableStateChangeListener();
-    service.register(listener);
+    service.registerServiceListener(listener);
     service.init(new Configuration());
     assertEventCount(listener, 1);
     //start the service
@@ -357,7 +357,7 @@ public class TestServiceLifecycle extends ServiceAssert {
   public void testStartInInitService() throws Throwable {
     Service service = new StartInInitService();
     BreakableStateChangeListener listener = new BreakableStateChangeListener();
-    service.register(listener);
+    service.registerServiceListener(listener);
     service.init(new Configuration());
     assertServiceInState(service, Service.STATE.STARTED);
     assertEventCount(listener, 1);
@@ -367,7 +367,7 @@ public class TestServiceLifecycle extends ServiceAssert {
   public void testStopInInitService() throws Throwable {
     Service service = new StopInInitService();
     BreakableStateChangeListener listener = new BreakableStateChangeListener();
-    service.register(listener);
+    service.registerServiceListener(listener);
     service.init(new Configuration());
     assertServiceInState(service, Service.STATE.STOPPED);
     assertEventCount(listener, 1);

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-nodemanager/src/main/java/org/apache/hadoop/yarn/server/nodemanager/containermanager/AuxServices.java

@@ -120,7 +120,7 @@ public class AuxServices extends AbstractService
       AuxiliaryService service = entry.getValue();
       String name = entry.getKey();
       service.start();
-      service.register(this);
+      service.registerServiceListener(this);
       ByteBuffer meta = service.getMeta();
       if(meta != null) {
         serviceMeta.put(name, meta);
@@ -135,7 +135,7 @@ public class AuxServices extends AbstractService
       synchronized (serviceMap) {
         for (Service service : serviceMap.values()) {
           if (service.getServiceState() == Service.STATE.STARTED) {
-            service.unregister(this);
+            service.unregisterServiceListener(this);
             service.stop();
           }
         }

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-nodemanager/src/main/java/org/apache/hadoop/yarn/server/nodemanager/containermanager/ContainerManagerImpl.java

@@ -156,7 +156,7 @@ public class ContainerManagerImpl extends CompositeService implements
 
     // Start configurable services
     auxiliaryServices = new AuxServices();
-    auxiliaryServices.register(this);
+    auxiliaryServices.registerServiceListener(this);
     addService(auxiliaryServices);
 
     this.containersMonitor =
@@ -265,7 +265,7 @@ public class ContainerManagerImpl extends CompositeService implements
   @Override
   public void serviceStop() throws Exception {
     if (auxiliaryServices.getServiceState() == STARTED) {
-      auxiliaryServices.unregister(this);
+      auxiliaryServices.unregisterServiceListener(this);
     }
     if (server != null) {
       server.stop();