Adding some base-classes to eliminate event and listener boiler-plate code throughout a number of subsystems.

Refactored all core components to take advantage of this; apps remain to be done.

Change-Id: Ib0935ba07ff81b0fa032534004ec9ac6187cbf22
diff --git a/incubator/net/pom.xml b/incubator/net/pom.xml
index 718f8ab..b068899 100644
--- a/incubator/net/pom.xml
+++ b/incubator/net/pom.xml
@@ -56,6 +56,11 @@
         </dependency>
 
         <dependency>
+            <groupId>org.onosproject</groupId>
+            <artifactId>onos-core-common</artifactId>
+        </dependency>
+
+        <dependency>
             <groupId>org.easymock</groupId>
             <artifactId>easymock</artifactId>
             <scope>test</scope>
diff --git a/incubator/net/src/main/java/org/onosproject/incubator/net/config/impl/NetworkConfigManager.java b/incubator/net/src/main/java/org/onosproject/incubator/net/config/impl/NetworkConfigManager.java
index a73cc8e..c295feb 100644
--- a/incubator/net/src/main/java/org/onosproject/incubator/net/config/impl/NetworkConfigManager.java
+++ b/incubator/net/src/main/java/org/onosproject/incubator/net/config/impl/NetworkConfigManager.java
@@ -24,8 +24,7 @@
 import org.apache.felix.scr.annotations.Reference;
 import org.apache.felix.scr.annotations.ReferenceCardinality;
 import org.apache.felix.scr.annotations.Service;
-import org.onosproject.event.EventDeliveryService;
-import org.onosproject.event.ListenerRegistry;
+import org.onosproject.event.AbstractListenerManager;
 import org.onosproject.incubator.net.config.Config;
 import org.onosproject.incubator.net.config.ConfigFactory;
 import org.onosproject.incubator.net.config.NetworkConfigEvent;
@@ -49,7 +48,9 @@
  */
 @Component(immediate = true)
 @Service
-public class NetworkConfigManager implements NetworkConfigRegistry, NetworkConfigService {
+public class NetworkConfigManager
+        extends AbstractListenerManager<NetworkConfigEvent, NetworkConfigListener>
+        implements NetworkConfigRegistry, NetworkConfigService {
 
     private final Logger log = LoggerFactory.getLogger(getClass());
 
@@ -66,17 +67,11 @@
     private final Map<Class, SubjectFactory> subjectClassKeys = Maps.newConcurrentMap();
     private final Map<ConfigIdentifier, Class<? extends Config>> configClasses = Maps.newConcurrentMap();
 
-    private final ListenerRegistry<NetworkConfigEvent, NetworkConfigListener>
-            listenerRegistry = new ListenerRegistry<>();
-
     private final NetworkConfigStoreDelegate storeDelegate = new InternalStoreDelegate();
 
     @Reference(cardinality = ReferenceCardinality.MANDATORY_UNARY)
     protected NetworkConfigStore store;
 
-    @Reference(cardinality = ReferenceCardinality.MANDATORY_UNARY)
-    protected EventDeliveryService eventDispatcher;
-
 
     @Activate
     public void activate() {
@@ -215,23 +210,12 @@
         store.clearConfig(subject, configClass);
     }
 
-    @Override
-    public void addListener(NetworkConfigListener listener) {
-        listenerRegistry.addListener(listener);
-    }
-
-    @Override
-    public void removeListener(NetworkConfigListener listener) {
-        listenerRegistry.removeListener(listener);
-    }
-
-
     // Auxiliary store delegate to receive notification about changes in
     // the network configuration store state - by the store itself.
     private class InternalStoreDelegate implements NetworkConfigStoreDelegate {
         @Override
         public void notify(NetworkConfigEvent event) {
-            eventDispatcher.post(event);
+            post(event);
         }
     }
 
diff --git a/incubator/net/src/main/java/org/onosproject/incubator/net/resource/label/impl/LabelResourceManager.java b/incubator/net/src/main/java/org/onosproject/incubator/net/resource/label/impl/LabelResourceManager.java
index 2836ea5..fecba11 100644
--- a/incubator/net/src/main/java/org/onosproject/incubator/net/resource/label/impl/LabelResourceManager.java
+++ b/incubator/net/src/main/java/org/onosproject/incubator/net/resource/label/impl/LabelResourceManager.java
@@ -1,26 +1,13 @@
 package org.onosproject.incubator.net.resource.label.impl;
 
-import static org.slf4j.LoggerFactory.getLogger;
-
-import java.util.Collection;
-import java.util.Set;
-
+import com.google.common.collect.Multimap;
 import org.apache.felix.scr.annotations.Activate;
 import org.apache.felix.scr.annotations.Component;
 import org.apache.felix.scr.annotations.Deactivate;
 import org.apache.felix.scr.annotations.Reference;
 import org.apache.felix.scr.annotations.ReferenceCardinality;
 import org.apache.felix.scr.annotations.Service;
-import org.onosproject.event.EventDeliveryService;
-import org.onosproject.event.ListenerRegistry;
-import org.onosproject.net.Device;
-import org.onosproject.net.DeviceId;
-import org.onosproject.net.device.DeviceEvent;
-import org.onosproject.net.device.DeviceEvent.Type;
-import org.onosproject.net.device.DeviceListener;
-import org.onosproject.net.device.DeviceService;
-import org.onosproject.net.provider.AbstractProviderRegistry;
-import org.onosproject.net.provider.AbstractProviderService;
+import org.onosproject.net.provider.AbstractListenerProviderRegistry;
 import org.onosproject.incubator.net.resource.label.LabelResource;
 import org.onosproject.incubator.net.resource.label.LabelResourceAdminService;
 import org.onosproject.incubator.net.resource.label.LabelResourceDelegate;
@@ -33,11 +20,21 @@
 import org.onosproject.incubator.net.resource.label.LabelResourceProviderService;
 import org.onosproject.incubator.net.resource.label.LabelResourceService;
 import org.onosproject.incubator.net.resource.label.LabelResourceStore;
+import org.onosproject.net.Device;
+import org.onosproject.net.DeviceId;
+import org.onosproject.net.device.DeviceEvent;
+import org.onosproject.net.device.DeviceEvent.Type;
+import org.onosproject.net.device.DeviceListener;
+import org.onosproject.net.device.DeviceService;
+import org.onosproject.net.provider.AbstractProviderService;
 import org.slf4j.Logger;
-import static com.google.common.base.Preconditions.checkNotNull;
-import static com.google.common.base.Preconditions.checkArgument;
 
-import com.google.common.collect.Multimap;
+import java.util.Collection;
+import java.util.Set;
+
+import static com.google.common.base.Preconditions.checkArgument;
+import static com.google.common.base.Preconditions.checkNotNull;
+import static org.slf4j.LoggerFactory.getLogger;
 
 /**
  * provides implementation of the label resource NB &amp; SB APIs.
@@ -46,23 +43,16 @@
 @Component(immediate = true)
 @Service
 public class LabelResourceManager
-        extends
-        AbstractProviderRegistry<LabelResourceProvider, LabelResourceProviderService>
-        implements LabelResourceService, LabelResourceAdminService,
-        LabelResourceProviderRegistry {
+        extends AbstractListenerProviderRegistry<LabelResourceEvent, LabelResourceListener,
+                                                 LabelResourceProvider, LabelResourceProviderService>
+        implements LabelResourceService, LabelResourceAdminService, LabelResourceProviderRegistry {
     private final Logger log = getLogger(getClass());
     private final LabelResourceDelegate delegate = new InternalLabelResourceDelegate();
 
-    private final ListenerRegistry<LabelResourceEvent, LabelResourceListener> listenerRegistry
-                            = new ListenerRegistry<>();
-
     @Reference(cardinality = ReferenceCardinality.MANDATORY_UNARY)
     protected LabelResourceStore store;
 
     @Reference(cardinality = ReferenceCardinality.MANDATORY_UNARY)
-    protected EventDeliveryService eventDispatcher;
-
-    @Reference(cardinality = ReferenceCardinality.MANDATORY_UNARY)
     protected DeviceService deviceService;
 
     private DeviceListener deviceListener = new InternalDeviceListener();
@@ -104,9 +94,9 @@
         checkNotNull(beginLabel, "beginLabel is not null");
         checkNotNull(endLabel, "beginLabel is not null");
         checkArgument(beginLabel.labelId() >= 0 && endLabel.labelId() >= 0,
-                "The value of beginLabel and the value of endLabel must be both positive number.");
+                      "The value of beginLabel and the value of endLabel must be both positive number.");
         checkArgument(beginLabel.labelId() <= endLabel.labelId(),
-                "The value of endLabel must be greater than the value of endLabel.");
+                      "The value of endLabel must be greater than the value of endLabel.");
         return store.createGlobalPool(beginLabel, endLabel);
     }
 
@@ -180,26 +170,7 @@
         return store.getGlobalLabelResourcePool();
     }
 
-    @Override
-    public void addListener(LabelResourceListener listener) {
-        listenerRegistry.addListener(listener);
-    }
-
-    @Override
-    public void removeListener(LabelResourceListener listener) {
-        listenerRegistry.removeListener(listener);
-
-    }
-
-    private void post(LabelResourceEvent event) {
-        if (event != null) {
-            eventDispatcher.post(event);
-        }
-    }
-
-    private class InternalLabelResourceDelegate
-            implements LabelResourceDelegate {
-
+    private class InternalLabelResourceDelegate implements LabelResourceDelegate {
         @Override
         public void notify(LabelResourceEvent event) {
             post(event);
@@ -208,7 +179,6 @@
     }
 
     private class InternalDeviceListener implements DeviceListener {
-
         @Override
         public void event(DeviceEvent event) {
             Device device = event.subject();
diff --git a/incubator/net/src/main/java/org/onosproject/incubator/net/tunnel/impl/TunnelManager.java b/incubator/net/src/main/java/org/onosproject/incubator/net/tunnel/impl/TunnelManager.java
index bb344b7..d316388 100644
--- a/incubator/net/src/main/java/org/onosproject/incubator/net/tunnel/impl/TunnelManager.java
+++ b/incubator/net/src/main/java/org/onosproject/incubator/net/tunnel/impl/TunnelManager.java
@@ -15,25 +15,17 @@
  */
 package org.onosproject.incubator.net.tunnel.impl;
 
-import static com.google.common.base.Preconditions.checkNotNull;
-import static org.slf4j.LoggerFactory.getLogger;
-
-import java.util.Collection;
-import java.util.Collections;
-import java.util.Set;
-
 import org.apache.felix.scr.annotations.Activate;
 import org.apache.felix.scr.annotations.Component;
 import org.apache.felix.scr.annotations.Deactivate;
 import org.apache.felix.scr.annotations.Reference;
 import org.apache.felix.scr.annotations.ReferenceCardinality;
 import org.apache.felix.scr.annotations.Service;
+import org.onosproject.net.provider.AbstractListenerProviderRegistry;
 import org.onosproject.core.ApplicationId;
-import org.onosproject.event.EventDeliveryService;
-import org.onosproject.event.ListenerRegistry;
 import org.onosproject.incubator.net.tunnel.DefaultTunnel;
-import org.onosproject.incubator.net.tunnel.Tunnel.Type;
 import org.onosproject.incubator.net.tunnel.Tunnel;
+import org.onosproject.incubator.net.tunnel.Tunnel.Type;
 import org.onosproject.incubator.net.tunnel.TunnelAdminService;
 import org.onosproject.incubator.net.tunnel.TunnelDescription;
 import org.onosproject.incubator.net.tunnel.TunnelEndPoint;
@@ -51,35 +43,36 @@
 import org.onosproject.net.Annotations;
 import org.onosproject.net.DeviceId;
 import org.onosproject.net.Path;
-import org.onosproject.net.provider.AbstractProviderRegistry;
 import org.onosproject.net.provider.AbstractProviderService;
 import org.onosproject.net.provider.ProviderId;
 import org.slf4j.Logger;
 
+import java.util.Collection;
+import java.util.Collections;
+import java.util.Set;
+
+import static com.google.common.base.Preconditions.checkNotNull;
+import static org.slf4j.LoggerFactory.getLogger;
+
 /**
  * Provides implementation of the tunnel NB/SB APIs.
  */
 @Component(immediate = true, enabled = true)
 @Service
 public class TunnelManager
-        extends AbstractProviderRegistry<TunnelProvider, TunnelProviderService>
+        extends AbstractListenerProviderRegistry<TunnelEvent, TunnelListener,
+                                                 TunnelProvider, TunnelProviderService>
         implements TunnelService, TunnelAdminService, TunnelProviderRegistry {
 
     private static final String TUNNNEL_ID_NULL = "Tunnel ID cannot be null";
 
     private final Logger log = getLogger(getClass());
 
-    protected final ListenerRegistry<TunnelEvent, TunnelListener>
-            listenerRegistry = new ListenerRegistry<>();
-
     private final TunnelStoreDelegate delegate = new InternalStoreDelegate();
 
-
     @Reference(cardinality = ReferenceCardinality.MANDATORY_UNARY)
     protected TunnelStore store;
 
-    @Reference(cardinality = ReferenceCardinality.MANDATORY_UNARY)
-    protected EventDeliveryService eventDispatcher;
 
     @Activate
     public void activate() {
@@ -294,16 +287,6 @@
         return new InternalTunnelProviderService(provider);
     }
 
-    @Override
-    public void addListener(TunnelListener listener) {
-        listenerRegistry.addListener(listener);
-    }
-
-    @Override
-    public void removeListener(TunnelListener listener) {
-        listenerRegistry.removeListener(listener);
-    }
-
     private class InternalTunnelProviderService
             extends AbstractProviderService<TunnelProvider>
             implements TunnelProviderService {
@@ -370,7 +353,7 @@
         @Override
         public void notify(TunnelEvent event) {
             if (event != null) {
-                eventDispatcher.post(event);
+                post(event);
             }
         }
     }