HADOOP-6570. RPC#stopProxy throws NPE if getProxyEngine(proxy) returns null. Contributed by Hairong Kuang.

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/trunk@911134 13f79535-47bb-0310-9956-ffa450edef68

CHANGES.txt

@@ -207,6 +207,9 @@ Trunk (unreleased changes)
     HADOOP-6549. TestDoAsEffectiveUser should use ip address of the host
      for superuser ip check(jnp via boryas)
 
+    HADOOP-6570. RPC#stopProxy throws NPE if getProxyEngine(proxy) returns
+    null. (hairong)
+
 Release 0.21.0 - Unreleased
 
   INCOMPATIBLE CHANGES

src/java/org/apache/hadoop/ipc/RPC.java

@@ -244,8 +244,9 @@ public class RPC {
    * @param proxy the proxy to be stopped
    */
   public static void stopProxy(Object proxy) {
-    if (proxy!=null) {
-      getProxyEngine(proxy).stopProxy(proxy);
+    RpcEngine rpcEngine;
+    if (proxy!=null && (rpcEngine = getProxyEngine(proxy)) != null) {
+      rpcEngine.stopProxy(proxy);
     }
   }
 

src/test/core/org/apache/hadoop/ipc/TestRPC.java

@@ -39,6 +39,8 @@ import org.apache.hadoop.security.authorize.PolicyProvider;
 import org.apache.hadoop.security.authorize.Service;
 import org.apache.hadoop.security.authorize.ServiceAuthorizationManager;
 
+import static org.mockito.Mockito.*;
+
 /** Unit tests for RPC. */
 public class TestRPC extends TestCase {
   private static final String ADDRESS = "0.0.0.0";
@@ -392,6 +394,14 @@ public class TestRPC extends TestCase {
     conf.setBoolean("ipc.client.ping", false);
     new TestRPC("testnoPings").testCalls(conf);
   }
+
+  /**
+   * Test stopping a non-registered proxy
+   * @throws Exception
+   */
+  public void testStopNonRegisteredProxy() throws Exception {
+    RPC.stopProxy(mock(TestProtocol.class));
+  }
   
   public static void main(String[] args) throws Exception {