Backport of HADOOP-9450. HADOOP_USER_CLASSPATH_FIRST is not honored; CLASSPATH is PREpended instead of APpended. Contributed by Chris Nauroth and Harsh J. (harsh)

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-1@1469216 13f79535-47bb-0310-9956-ffa450edef68

CHANGES.txt

@@ -8,6 +8,9 @@ Release 1.3.0 - unreleased
 
   IMPROVEMENTS
 
+    HADOOP-9450. HADOOP_USER_CLASSPATH_FIRST is not honored; CLASSPATH
+    is PREpended instead of APpended. (Chris Nauroth and harsh via harsh)
+
   BUG FIXES
 
     MAPREDUCE-5047. keep.failed.task.files=true causes job failure on 

bin/hadoop

@@ -152,9 +152,7 @@ fi
 
 # CLASSPATH initially contains $HADOOP_CONF_DIR
 CLASSPATH="${HADOOP_CONF_DIR}"
-if [ "$HADOOP_USER_CLASSPATH_FIRST" != "" ] && [ "$HADOOP_CLASSPATH" != "" ] ; then
-  CLASSPATH=${CLASSPATH}:${HADOOP_CLASSPATH}
-fi
+
 CLASSPATH=${CLASSPATH}:$JAVA_HOME/lib/tools.jar
 
 # for developers, add Hadoop classes to CLASSPATH
@@ -228,9 +226,16 @@ else
   done
 fi
 
-# add user-specified CLASSPATH last
-if [ "$HADOOP_USER_CLASSPATH_FIRST" = "" ] && [ "$HADOOP_CLASSPATH" != "" ]; then
-  CLASSPATH=${CLASSPATH}:${HADOOP_CLASSPATH}
+# Add the user-specified CLASSPATH via HADOOP_CLASSPATH
+# Add it first or last depending on if user has
+# set env-var HADOOP_USER_CLASSPATH_FIRST
+if [ "$HADOOP_CLASSPATH" != "" ]; then
+  # Prefix it if its to be preceded
+  if [ "$HADOOP_USER_CLASSPATH_FIRST" != "" ]; then
+    CLASSPATH=${HADOOP_CLASSPATH}:${CLASSPATH}
+  else
+    CLASSPATH=${CLASSPATH}:${HADOOP_CLASSPATH}
+  fi
 fi
 
 # default log directory & file