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diff --git a/ecomp-sdk-app/src/main/java/org/openecomp/policy/admin/PAPNotificationBroadcaster.java b/ecomp-sdk-app/src/main/java/org/openecomp/policy/admin/PAPNotificationBroadcaster.java
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+++ b/ecomp-sdk-app/src/main/java/org/openecomp/policy/admin/PAPNotificationBroadcaster.java
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+/*-
+ * ============LICENSE_START=======================================================
+ * ECOMP Policy Engine
+ * ================================================================================
+ * Copyright (C) 2017 AT&T Intellectual Property. All rights reserved.
+ * ================================================================================
+ * Licensed under the Apache License, Version 2.0 (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.apache.org/licenses/LICENSE-2.0
+ * 
+ * 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.
+ * ============LICENSE_END=========================================================
+ */
+
+package org.openecomp.policy.admin;
+
+
+import java.io.Serializable;
+import java.util.LinkedList;
+import java.util.concurrent.ExecutorService;
+import java.util.concurrent.Executors;
+
+
+import org.openecomp.policy.common.logging.flexlogger.FlexLogger; 
+import org.openecomp.policy.common.logging.flexlogger.Logger;
+
+/**
+ * Handle Notifications from the PAP that the PDP Groups have been changed.
+ * We need a Server Push Broadcaster because there may be multiple Vaadin instances (i.e. Users) that need to be told when a change occurs.
+ * 
+ * Initially we only update the entire set of PDPGroups in one shot.
+ * 
+ * (Code copied from Book of Vaadin chapter on Server Push
+ *
+ */
+public class PAPNotificationBroadcaster implements Serializable {
+	/**
+	 * 
+	 */
+	private static final long serialVersionUID = -2539940306348821754L;
+
+
+	private static Logger logger	= FlexLogger.getLogger(PAPNotificationBroadcaster.class);
+
+	
+    static ExecutorService executorService = Executors.newSingleThreadExecutor();
+
+    /**
+     * Interface used by all classes that need to be notified when PAP sends an update message.
+     * 
+     *
+     */
+    public interface PAPNotificationBroadcastListener {
+        void updateAllGroups();
+    }
+    
+    
+    
+    /*
+     * list of registered listeners
+     */
+    private static LinkedList<PAPNotificationBroadcastListener> listeners =
+        new LinkedList<PAPNotificationBroadcastListener>();
+    
+    /**
+     * Listener registers to hear about updates.
+     * @param listener
+     */
+    public static synchronized void register(
+    		PAPNotificationBroadcastListener listener) {
+        listeners.add(listener);
+    }
+    
+    
+    /**
+     * Listener is going away.
+     * 
+     * @param listener
+     */
+    public static synchronized void unregister(
+    		PAPNotificationBroadcastListener listener) {
+        listeners.remove(listener);
+    }
+    
+    
+    
+    /**
+     * Tell all listeners about an update.
+     * 
+     * @param message
+     */
+    public static synchronized void updateAllGroups() {
+        for (final PAPNotificationBroadcastListener listener: listeners) {
+  // Original code copied from example:
+  //          executorService.execute(new Runnable() {
+  //              @Override
+  //              public void run() {
+  // The problem with this is that the execute starts a new Thread, but the thing we are calling (the listener.updateAllGroups)
+  // happens in this case to ALSO create a new thread, and it locks up because the shared threadpool queue is already locked by this method.
+  // On application shutdown that left us with a blocked thread, so the process never goes away.
+  // Since the listener.updateAllGroups does ALL of its work inside a new Runnable thread, there should be no need for this method to also create a thread.
+  
+        	/*
+        	 * IMPORTANT:
+        	 * All listeners MUST either execute with no possibility of blocking
+        	 * OR must start their own threads to handle blocking and concurrent operations.
+        	 */
+        	if (logger.isDebugEnabled()) {
+        		logger.debug("updateAllGroups");
+        	}
+            listener.updateAllGroups();
+        }
+    }
+}