From 2b7ae8dd5d9718b76d7ac98e0808c99a9ac677cc Mon Sep 17 00:00:00 2001
From: Jason Darrell Lowe <jlowe@apache.org>
Date: Thu, 26 Sep 2013 21:21:34 +0000
Subject: [PATCH] svn merge -c 1526688 FIXES: MAPREDUCE-5513.
 ConcurrentModificationException in JobControl. Contributed by Robert Parker

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-2@1526702 13f79535-47bb-0310-9956-ffa450edef68
---
 hadoop-mapreduce-project/CHANGES.txt                      | 6 ++++++
 .../hadoop/mapreduce/lib/jobcontrol/JobControl.java       | 8 +++-----
 2 files changed, 9 insertions(+), 5 deletions(-)

diff --git a/hadoop-mapreduce-project/CHANGES.txt b/hadoop-mapreduce-project/CHANGES.txt
index eb4cee8ff62..38d16ca66f4 100644
--- a/hadoop-mapreduce-project/CHANGES.txt
+++ b/hadoop-mapreduce-project/CHANGES.txt
@@ -90,6 +90,9 @@ Release 2.1.2 - UNRELEASED
     MAPREDUCE-5525. Increase timeout of TestDFSIO.testAppend and
     TestMRJobsWithHistoryService.testJobHistoryData. (Chuan Liu via cnauroth)
 
+    MAPREDUCE-5513. ConcurrentModificationException in JobControl (Robert
+    Parker via jlowe)
+
 Release 2.1.1-beta - 2013-09-23
 
   INCOMPATIBLE CHANGES
@@ -1284,6 +1287,9 @@ Release 0.23.10 - UNRELEASED
     MAPREDUCE-5504. mapred queue -info inconsistent with types (Kousuke Saruta
     via tgraves)
 
+    MAPREDUCE-5513. ConcurrentModificationException in JobControl (Robert
+    Parker via jlowe)
+
 Release 0.23.9 - 2013-07-08
 
   INCOMPATIBLE CHANGES
diff --git a/hadoop-mapreduce-project/hadoop-mapreduce-client/hadoop-mapreduce-client-core/src/main/java/org/apache/hadoop/mapreduce/lib/jobcontrol/JobControl.java b/hadoop-mapreduce-project/hadoop-mapreduce-client/hadoop-mapreduce-client-core/src/main/java/org/apache/hadoop/mapreduce/lib/jobcontrol/JobControl.java
index a76e36f349c..59e3331875b 100644
--- a/hadoop-mapreduce-project/hadoop-mapreduce-client/hadoop-mapreduce-client-core/src/main/java/org/apache/hadoop/mapreduce/lib/jobcontrol/JobControl.java
+++ b/hadoop-mapreduce-project/hadoop-mapreduce-client/hadoop-mapreduce-client-core/src/main/java/org/apache/hadoop/mapreduce/lib/jobcontrol/JobControl.java
@@ -77,13 +77,11 @@ public JobControl(String groupName) {
     this.runnerState = ThreadState.READY;
   }
 	
-  private static List<ControlledJob> toList(
+  synchronized private static List<ControlledJob> toList(
                    LinkedList<ControlledJob> jobs) {
     ArrayList<ControlledJob> retv = new ArrayList<ControlledJob>();
-    synchronized (jobs) {
-      for (ControlledJob job : jobs) {
-        retv.add(job);
-      }
+    for (ControlledJob job : jobs) {
+      retv.add(job);
     }
     return retv;
   }