HADOOP-365. Fix a ClassCastException introduced by HADOOP-354. Patch contributed by Owen.

git-svn-id: https://svn.apache.org/repos/asf/lucene/hadoop/trunk@423019 13f79535-47bb-0310-9956-ffa450edef68

src/java/org/apache/hadoop/dfs/DataNode.java

@@ -904,7 +904,7 @@ public class DataNode implements FSConstants, Runnable {
 
     //  Wait for sub threads to exit
     for (Iterator iterator = subDataNodeList.entrySet().iterator(); iterator.hasNext();) {
-      Thread threadDataNode = (Thread) iterator.next();
+      Thread threadDataNode = (Thread) ((Map.Entry) iterator.next()).getValue();
       try {
         threadDataNode.join();
       } catch (InterruptedException e) {