MAPREDUCE-4869. Fix TestMapReduceChildJVM. Contributed by Chris Nauroth.

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-trunk-win@1426397 13f79535-47bb-0310-9956-ffa450edef68

hadoop-mapreduce-project/CHANGES.branch-trunk-win.txt

@@ -8,3 +8,6 @@ branch-trunk-win changes - unreleased
 
   MAPREDUCE-4790. MapReduce build script would be more readable using abspath.
   (Chris Nauroth via suresh)
+
+  MAPREDUCE-4869. Fix TestMapReduceChildJVM. (Chris Nauroth via acmurthy)
+

hadoop-mapreduce-project/hadoop-mapreduce-client/hadoop-mapreduce-client-app/src/test/java/org/apache/hadoop/mapreduce/v2/app/job/impl/TestMapReduceChildJVM.java

@@ -30,6 +30,7 @@ import org.apache.hadoop.mapreduce.v2.app.job.Job;
 import org.apache.hadoop.mapreduce.v2.app.launcher.ContainerLauncher;
 import org.apache.hadoop.mapreduce.v2.app.launcher.ContainerLauncherEvent;
 import org.apache.hadoop.mapreduce.v2.app.launcher.ContainerRemoteLaunchEvent;
+import org.apache.hadoop.util.Shell;
 import org.apache.hadoop.yarn.api.records.ContainerLaunchContext;
 import org.junit.Test;
 
@@ -46,10 +47,10 @@ public class TestMapReduceChildJVM {
     app.verifyCompleted();
 
     Assert.assertEquals(
-      "[exec $JAVA_HOME/bin/java" +
+      "[" + envVar("JAVA_HOME") + "/bin/java" +
       " -Djava.net.preferIPv4Stack=true" +
       " -Dhadoop.metrics.log.level=WARN" +
-      "  -Xmx200m -Djava.io.tmpdir=$PWD/tmp" +
+      "  -Xmx200m -Djava.io.tmpdir=" + envVar("PWD") + "/tmp" +
       " -Dlog4j.configuration=container-log4j.properties" +
       " -Dyarn.app.mapreduce.container.log.dir=<LOG_DIR>" +
       " -Dyarn.app.mapreduce.container.log.filesize=0" +
@@ -88,4 +89,16 @@ public class TestMapReduceChildJVM {
       };
     }
   }
+
+  /**
+   * Returns platform-specific string for retrieving the value of an environment
+   * variable with the given name.  On Unix, this returns $name.  On Windows,
+   * this returns %name%.
+   * 
+   * @param name String environment variable name
+   * @return String for retrieving value of environment variable
+   */
+  private static String envVar(String name) {
+    return Shell.WINDOWS ? '%' + name + '%' : '$' + name;
+  }
 }