BUG-1120: introduce NotificationListenerMap

[controller.git] / opendaylight / md-sal / sal-binding-broker / src / main / java / org / opendaylight / controller / sal / binding / impl / NotificationListenerMap.java

diff --git a/opendaylight/md-sal/sal-binding-broker/src/main/java/org/opendaylight/controller/sal/binding/impl/NotificationListenerMap.java b/opendaylight/md-sal/sal-binding-broker/src/main/java/org/opendaylight/controller/sal/binding/impl/NotificationListenerMap.java
new file mode 100644 (file)
index 0000000..d3039fe
--- /dev/null
+++ b/opendaylight/md-sal/sal-binding-broker/src/main/java/org/opendaylight/controller/sal/binding/impl/NotificationListenerMap.java
@@ -0,0 +1,70 @@
+/**
+ * Copyright (c) 2013 Cisco Systems, Inc. and others.  All rights reserved.
+ *
+ * This program and the accompanying materials are made available under the
+ * terms of the Eclipse Public License v1.0 which accompanies this distribution,
+ * and is available at http://www.eclipse.org/legal/epl-v10.html
+ */
+package org.opendaylight.controller.sal.binding.impl;
+
+import java.util.Arrays;
+import java.util.Collection;
+import java.util.HashSet;
+import java.util.Set;
+
+import org.opendaylight.yangtools.yang.binding.Notification;
+
+import com.google.common.base.Predicate;
+import com.google.common.collect.HashMultimap;
+import com.google.common.collect.ImmutableList;
+import com.google.common.collect.Iterables;
+import com.google.common.collect.Multimap;
+import com.google.common.collect.Multimaps;
+
+final class NotificationListenerMap {
+    private final Multimap<Class<? extends Notification>, NotificationListenerRegistration<?>> listeners =
+            Multimaps.synchronizedSetMultimap(HashMultimap.<Class<? extends Notification>, NotificationListenerRegistration<?>>create());
+
+    private static Iterable<Class<?>> getNotificationTypes(final Notification notification) {
+        final Class<?>[] ifaces = notification.getClass().getInterfaces();
+        return Iterables.filter(Arrays.asList(ifaces), new Predicate<Class<?>>() {
+            @Override
+            public boolean apply(final Class<?> input) {
+                if (Notification.class.equals(input)) {
+                    return false;
+                }
+                return Notification.class.isAssignableFrom(input);
+            }
+        });
+    }
+
+    Iterable<NotificationListenerRegistration<?>> listenersFor(final Notification notification) {
+        final Set<NotificationListenerRegistration<?>> toNotify = new HashSet<>();
+
+        for (final Class<?> type : getNotificationTypes(notification)) {
+            final Collection<NotificationListenerRegistration<?>> l = listeners.get((Class<? extends Notification>) type);
+            if (l != null) {
+                toNotify.addAll(l);
+            }
+        }
+
+        return toNotify;
+    }
+
+    Iterable<Class<? extends Notification>> getKnownTypes() {
+        return ImmutableList.copyOf(listeners.keySet());
+    }
+
+    void addRegistrations(final NotificationListenerRegistration<?>... registrations) {
+        for (NotificationListenerRegistration<?> reg : registrations) {
+            listeners.put(reg.getType(), reg);
+        }
+    }
+
+    void removeRegistrations(final NotificationListenerRegistration<?>... registrations) {
+        for (NotificationListenerRegistration<?> reg : registrations) {
+            listeners.remove(reg.getType(), reg);
+        }
+    }
+
+}