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editor/tools/plugins/com.google.dart.tools.core/src/com/google/dart/tools/core/pub/PubManager.java

Index: editor/tools/plugins/com.google.dart.tools.core/src/com/google/dart/tools/core/pub/PubManager.java
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--- editor/tools/plugins/com.google.dart.tools.core/src/com/google/dart/tools/core/pub/PubManager.java	(revision 0)
+++ editor/tools/plugins/com.google.dart.tools.core/src/com/google/dart/tools/core/pub/PubManager.java	(revision 0)
@@ -0,0 +1,47 @@
+/*
+ * Copyright (c) 2012, the Dart project authors.
+ * 
+ * Licensed under the Eclipse Public License v1.0 (the "License"); you may not use this file except
+ * in compliance with the License. You may obtain a copy of the License at
+ * 
+ * http://www.eclipse.org/legal/epl-v10.html
+ * 
+ * Unless required by applicable law or agreed to in writing, software distributed under the License
+ * is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express
+ * or implied. See the License for the specific language governing permissions and limitations under
+ * the License.
+ */
+package com.google.dart.tools.core.pub;
+
+import org.eclipse.core.resources.IContainer;
+import org.eclipse.core.runtime.ListenerList;
+
+/**
+ * The unique instance of the class <code>PubManager</code> is used to manage the listeners for pub
+ * updates.
+ */
+public class PubManager {
+
+  private static final PubManager INSTANCE = new PubManager();
+
+  public synchronized static PubManager getInstance() {
+    return INSTANCE;
+  }
+
+  private final ListenerList listeners = new ListenerList();
+
+  public void addListener(IPubUpdateListener listener) {
+    listeners.add(listener);
+  }
+
+  public void notifyListeners(IContainer container) {
+    for (Object listener : listeners.getListeners()) {
+      ((IPubUpdateListener) listener).packagesUpdated(container);
+    }
+  }
+
+  public void removeListener(IPubUpdateListener listener) {
+    listeners.remove(listener);
+  }
+
+}