Add methods to remove entities from Node

rcljava/src/main/java/org/ros2/rcljava/client/ClientImpl.java

@@ -131,6 +131,7 @@ public final Class<MessageDefinition> getResponseType() {
   public final void dispose() {
     Node node = this.nodeReference.get();
     if (node != null) {
+      node.removeClient(this);
       nativeDispose(node.getHandle(), this.handle);
       this.handle = 0;
     }

rcljava/src/main/java/org/ros2/rcljava/node/Node.java

@@ -122,6 +122,55 @@ <T extends ServiceDefinition> Client<T> createClient(
   <T extends ServiceDefinition> Client<T> createClient(final Class<T> serviceType,
       final String serviceName) throws NoSuchFieldException, IllegalAccessException;
 
+  /**
+   * Remove a Subscription created by this Node.
+   *
+   * Calling this method effectively invalidates the passed @{link Subscription}.
+   * If the subscription was not created by this Node, then nothing happens.
+   *
+   * @param subscription The object to remove from this node.
+   * @return true if the subscription was removed, false if the subscription was already
+   *   removed or was never created by this Node.
+   */
+  boolean removeSubscription(final Subscription subscription);
+
+  /**
+   * Remove a Publisher created by this Node.
+   *
+   * Calling this method effectively invalidates the passed @{link Publisher}.
+   * If the publisher was not created by this Node, then nothing happens.
+   *
+   * @param publisher The object to remove from this node.
+   * @return true if the publisher was removed, false if the publisher was already
+   *   removed or was never created by this Node.
+   */
+  boolean removePublisher(final Publisher publisher);
+
+  /**
+   * Remove a Service created by this Node.
+   *
+   * Calling this method effectively invalidates the passed @{link Service}.
+   * If the service was not created by this Node, then nothing happens.
+   *
+   * @param service The object to remove from this node.
+   * @return true if the service was removed, false if the service was already
+   *   removed or was never created by this Node.
+   */
+  boolean removeService(final Service service);
+
+  /**
+   * Remove a Client created by this Node.
+   *
+   * Calling this method effectively invalidates the passed @{link Client}.
+   * If the client was not created by this Node, then nothing happens.
+   *
+   * @param client The object to remove from this node.
+   * @return true if the client was removed, false if the client was already
+   *   removed or was never created by this Node.
+   */
+  boolean removeClient(final Client client);
+
+
   WallTimer createWallTimer(final long period, final TimeUnit unit, final Callback callback);
 
   String getName();

rcljava/src/main/java/org/ros2/rcljava/node/NodeImpl.java

@@ -221,6 +221,20 @@ public final <T extends MessageDefinition> Subscription<T> createSubscription(
     return this.<T>createSubscription(messageType, topic, callback, QoSProfile.DEFAULT);
   }
 
+  /**
+   * {@inheritDoc}
+   */
+  public boolean removeSubscription(final Subscription subscription) {
+    return this.subscriptions.remove(subscription);
+  }
+
+  /**
+   * {@inheritDoc}
+   */
+  public boolean removePublisher(final Publisher publisher) {
+    return this.publishers.remove(publisher);
+  }
+
   /**
    * {@inheritDoc}
    */
@@ -300,6 +314,20 @@ public <T extends ServiceDefinition> Client<T> createClient(final Class<T> servi
   private static native <T extends ServiceDefinition> long nativeCreateClientHandle(
       long handle, Class<T> cls, String serviceName, long qosProfileHandle);
 
+  /**
+   * {@inheritDoc}
+   */
+  public boolean removeService(final Service service) {
+    return this.services.remove(service);
+  }
+
+  /**
+   * {@inheritDoc}
+   */
+  public boolean removeClient(final Client client) {
+    return this.clients.remove(client);
+  }
+
   /**
    * {@inheritDoc}
    */

rcljava/src/main/java/org/ros2/rcljava/publisher/PublisherImpl.java

@@ -117,6 +117,7 @@ public final WeakReference<Node> getNodeReference() {
   public final void dispose() {
     Node node = this.nodeReference.get();
     if (node != null) {
+      node.removePublisher(this);
       nativeDispose(node.getHandle(), this.handle);
       this.handle = 0;
     }

rcljava/src/main/java/org/ros2/rcljava/service/ServiceImpl.java

@@ -85,6 +85,7 @@ public final Class<MessageDefinition> getResponseType() {
   public final void dispose() {
     Node node = this.nodeReference.get();
     if (node != null) {
+      node.removeService(this);
       nativeDispose(node.getHandle(), this.handle);
       this.handle = 0;
     }

rcljava/src/main/java/org/ros2/rcljava/subscription/SubscriptionImpl.java

@@ -129,6 +129,7 @@ public final WeakReference<Node> getNodeReference() {
   public final void dispose() {
     Node node = this.nodeReference.get();
     if (node != null) {
+      node.removeSubscription(this);
       nativeDispose(node.getHandle(), this.handle);
       this.handle = 0;
     }

rcljava/src/test/java/org/ros2/rcljava/client/ClientTest.java

@@ -111,10 +111,16 @@ public final void testAdd() throws Exception {
     // Check the contents of the response
     assertEquals(5, response.getSum());
 
-    // Cleanup
+    assertEquals(1, node.getClients().size());
+    assertEquals(1, node.getServices().size());
+
+    // We expect that calling dispose should result in a zero handle
+    // and the reference is dropped from the Node
     client.dispose();
     assertEquals(0, client.getHandle());
+    assertEquals(0, node.getClients().size());
     service.dispose();
     assertEquals(0, service.getHandle());
+    assertEquals(0, node.getServices().size());
   }
 }

rcljava/src/test/java/org/ros2/rcljava/publisher/PublisherTest.java

@@ -25,14 +25,22 @@
 
 public class PublisherTest {
   @Test
-  public final void testCreate() {
+  public final void testCreateAndDispose() {
     RCLJava.rclJavaInit();
     Node node = RCLJava.createNode("test_node");
     Publisher<std_msgs.msg.String> publisher =
         node.<std_msgs.msg.String>createPublisher(std_msgs.msg.String.class, "test_topic");
     assertEquals(node.getHandle(), publisher.getNodeReference().get().getHandle());
     assertNotEquals(0, publisher.getNodeReference().get().getHandle());
     assertNotEquals(0, publisher.getHandle());
+    assertEquals(1, node.getPublishers().size());
+
+    // We expect that calling dispose should result in a zero handle
+    // and the reference is dropped from the Node
+    publisher.dispose();
+    assertEquals(0, publisher.getHandle());
+    assertEquals(0, node.getPublishers().size());
+
     RCLJava.shutdown();
   }
 }

rcljava/src/test/java/org/ros2/rcljava/subscription/SubscriptionTest.java

@@ -26,7 +26,7 @@
 
 public class SubscriptionTest {
   @Test
-  public final void testCreate() {
+  public final void testCreateAndDispose() {
     RCLJava.rclJavaInit();
     Node node = RCLJava.createNode("test_node");
     Subscription<std_msgs.msg.String> subscription = node.<std_msgs.msg.String>createSubscription(
@@ -36,6 +36,14 @@ public void accept(final std_msgs.msg.String msg) {}
     assertEquals(node.getHandle(), subscription.getNodeReference().get().getHandle());
     assertNotEquals(0, subscription.getNodeReference().get().getHandle());
     assertNotEquals(0, subscription.getHandle());
+    assertEquals(1, node.getSubscriptions().size());
+
+    // We expect that calling dispose should result in a zero handle
+    // and the reference is dropped from the Node
+    subscription.dispose();
+    assertEquals(0, subscription.getHandle());
+    assertEquals(0, node.getSubscriptions().size());
+
     RCLJava.shutdown();
   }
 }