Enhancments to rosjava/rosjava_core#237 fix. This moves shutdown...

Enhancments to rosjava/rosjava_core#237 fix. This moves shutdown responsibility to the topicParticipantManager.

rosjava/src/main/java/org/ros/internal/node/DefaultNode.java

@@ -405,14 +405,7 @@ public class DefaultNode implements ConnectedNode {
     // NOTE(damonkohler): We don't want to raise potentially spurious
     // exceptions during shutdown that would interrupt the process. This is
     // simply best effort cleanup.
-    for (DefaultPublisher<?> publisher : topicParticipantManager.getPublishers()) {
-      publisher.shutdown();
-      topicParticipantManager.removePublisher(publisher);
-    }
-    for (DefaultSubscriber<?> subscriber : topicParticipantManager.getSubscribers()) {
-      subscriber.shutdown();
-      topicParticipantManager.removeSubscriber(subscriber);
-    }
+    topicParticipantManager.shutdown();
     for (ServiceServer<?, ?> serviceServer : serviceManager.getServers()) {
       try {
         Response<Integer> response =

rosjava/src/main/java/org/ros/internal/node/topic/TopicParticipantManager.java

@@ -136,6 +136,19 @@ public class TopicParticipantManager {
     publisherConnections.remove(publisher, subscriberIdentifier);
   }
 
+  public void shutdown(){
+    for(DefaultPublisher<?> publisher : publishers.values()){
+      publisher.shutdown();
+      removePublisher(publisher);
+    }
+    subscriberConnections.clear();
+    for(DefaultSubscriber<?> subscriber : subscribers.values()){
+      subscriber.shutdown();
+      removeSubscriber(subscriber);
+    }
+    publisherConnections.clear();
+  }
+
   public Collection<DefaultSubscriber<?>> getSubscribers() {
     return ImmutableList.copyOf(subscribers.values());
   }