HDFS-7780. Update use of Iterator to Iterable in DataXceiverServer and SnapshotDiffInfo. Contributed by Ray Chiang.

hadoop-hdfs-project/hadoop-hdfs/CHANGES.txt

@@ -647,6 +647,9 @@ Release 2.7.0 - UNRELEASED
     HDFS-7795. Show warning if not all favored nodes were chosen by namenode
     (kihwal)
 
+    HDFS-7780. Update use of Iterator to Iterable in DataXceiverServer and
+    SnapshotDiffInfo. (Ray Chiang via aajisaka)
+
   OPTIMIZATIONS
 
     HDFS-7454. Reduce memory footprint for AclEntries in NameNode.

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/datanode/DataXceiverServer.java

@@ -252,9 +252,9 @@ class DataXceiverServer implements Runnable {
   // be set true before calling this method.
   synchronized void restartNotifyPeers() {
     assert (datanode.shouldRun == true && datanode.shutdownForUpgrade);
-    for (Peer p : peers.keySet()) {
+    for (Thread t : peers.values()) {
       // interrupt each and every DataXceiver thread.
-      peers.get(p).interrupt();
+      t.interrupt();
     }
   }
 

hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/namenode/snapshot/SnapshotDiffInfo.java

@@ -187,12 +187,13 @@ class SnapshotDiffInfo {
    */
   public SnapshotDiffReport generateReport() {
     List<DiffReportEntry> diffReportList = new ArrayList<DiffReportEntry>();
-    for (INode node : diffMap.keySet()) {
-      diffReportList.add(new DiffReportEntry(DiffType.MODIFY, diffMap
-          .get(node), null));
+    for (Map.Entry<INode,byte[][]> drEntry : diffMap.entrySet()) {
+      INode node = drEntry.getKey();
+      byte[][] path = drEntry.getValue();
+      diffReportList.add(new DiffReportEntry(DiffType.MODIFY, path, null));
       if (node.isDirectory()) {
         List<DiffReportEntry> subList = generateReport(dirDiffMap.get(node),
-            diffMap.get(node), isFromEarlier(), renameMap);
+            path, isFromEarlier(), renameMap);
         diffReportList.addAll(subList);
       }
     }