Add tests for disposing publishers, services, and clients

Signed-off-by: Jacob Perron <jacob@openrobotics.org>

Author: jacobperron

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

@@ -33,6 +33,14 @@ public final void testCreate() {
     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();
   }
 }