HADOOP-10017. Merge change r1529572 from branch-2.

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-2.1-beta@1529573 13f79535-47bb-0310-9956-ffa450edef68

hadoop-common-project/hadoop-common/CHANGES.txt

@@ -48,6 +48,9 @@ Release 2.1.2 - UNRELEASED
     HADOOP-10003. HarFileSystem.listLocatedStatus() fails.
     (Jason Dere and suresh via suresh)
 
+    HADOOP-10017. Fix NPE in DFSClient#getDelegationToken when doing Distcp 
+    from a secured cluster to an insecured cluster. (Haohui Mai via jing9)
+
 Release 2.1.1-beta - 2013-09-23
 
   INCOMPATIBLE CHANGES

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/DFSClient.java

@@ -846,10 +846,15 @@ public class DFSClient implements java.io.Closeable {
     assert dtService != null;
     Token<DelegationTokenIdentifier> token =
       namenode.getDelegationToken(renewer);
-    token.setService(this.dtService);
 
-    LOG.info("Created " + DelegationTokenIdentifier.stringifyToken(token));
+    if (token != null) {
+      token.setService(this.dtService);
+      LOG.info("Created " + DelegationTokenIdentifier.stringifyToken(token));
+    } else {
+      LOG.info("Cannot get delegation token from " + renewer);
+    }
     return token;
+
   }
 
   /**

hadoop-hdfs-project/hadoop-hdfs/src/test/java/org/apache/hadoop/hdfs/TestDistributedFileSystem.java

@@ -86,6 +86,19 @@ public class TestDistributedFileSystem {
     return conf;
   }
 
+  @Test
+  public void testEmptyDelegationToken() throws IOException {
+    Configuration conf = getTestConfiguration();
+    MiniDFSCluster cluster = null;
+    try {
+      cluster = new MiniDFSCluster.Builder(conf).numDataNodes(1).build();
+      FileSystem fileSys = cluster.getFileSystem();
+      fileSys.getDelegationToken("");
+    } finally {
+      cluster.shutdown();
+    }
+  }
+
   @Test
   public void testFileSystemCloseAll() throws Exception {
     Configuration conf = getTestConfiguration();