diff --git a/hadoop-mapreduce-project/CHANGES.txt b/hadoop-mapreduce-project/CHANGES.txt
index 7cd61f5bc30..879589e833d 100644
--- a/hadoop-mapreduce-project/CHANGES.txt
+++ b/hadoop-mapreduce-project/CHANGES.txt
@@ -376,6 +376,8 @@ Release 0.23.3 - UNRELEASED
 
     MAPREDUCE-4233. NPE can happen in RMNMNodeInfo. (bobby)
 
+    MAPREDUCE-4238. mavenize data_join. (tgraves)
+
 Release 0.23.2 - UNRELEASED
 
   INCOMPATIBLE CHANGES
diff --git a/hadoop-project/pom.xml b/hadoop-project/pom.xml
index 7ac4f120029..5466a88be1c 100644
--- a/hadoop-project/pom.xml
+++ b/hadoop-project/pom.xml
@@ -231,6 +231,11 @@
         <artifactId>hadoop-distcp</artifactId>
         <version>${project.version}</version>
       </dependency>
+      <dependency>
+        <groupId>org.apache.hadoop</groupId>
+        <artifactId>hadoop-datajoin</artifactId>
+        <version>${project.version}</version>
+      </dependency>
       <dependency>
         <groupId>org.apache.hadoop</groupId>
         <artifactId>hadoop-rumen</artifactId>
diff --git a/hadoop-tools/hadoop-datajoin/pom.xml b/hadoop-tools/hadoop-datajoin/pom.xml
new file mode 100644
index 00000000000..eed6d33bf66
--- /dev/null
+++ b/hadoop-tools/hadoop-datajoin/pom.xml
@@ -0,0 +1,120 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!--
+  Licensed under the Apache License, Version 2.0 (the "License");
+  you may not use this file except in compliance with the License.
+  You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+  Unless required by applicable law or agreed to in writing, software
+  distributed under the License is distributed on an "AS IS" BASIS,
+  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+  See the License for the specific language governing permissions and
+  limitations under the License. See accompanying LICENSE file.
+-->
+<project>
+  <modelVersion>4.0.0</modelVersion>
+  <parent>
+    <groupId>org.apache.hadoop</groupId>
+    <artifactId>hadoop-project</artifactId>
+    <version>2.0.0-SNAPSHOT</version>
+    <relativePath>../../hadoop-project</relativePath>
+  </parent>
+  <groupId>org.apache.hadoop</groupId>
+  <artifactId>hadoop-datajoin</artifactId>
+  <version>2.0.0-SNAPSHOT</version>
+  <description>Apache Hadoop Data Join</description>
+  <name>Apache Hadoop Data Join</name>
+  <packaging>jar</packaging>
+
+  <properties>
+    <hadoop.log.dir>${project.build.directory}/log</hadoop.log.dir>
+  </properties>
+
+  <dependencies>
+    <dependency>
+      <groupId>org.apache.hadoop</groupId>
+      <artifactId>hadoop-annotations</artifactId>
+      <scope>provided</scope>
+    </dependency>
+    <dependency>
+      <groupId>org.apache.hadoop</groupId>
+      <artifactId>hadoop-mapreduce-client-hs</artifactId>
+      <scope>provided</scope>
+    </dependency>
+    <dependency>
+      <groupId>org.apache.hadoop</groupId>
+      <artifactId>hadoop-mapreduce-client-core</artifactId>
+      <scope>provided</scope>
+    </dependency>
+    <dependency>
+      <groupId>org.apache.hadoop</groupId>
+      <artifactId>hadoop-mapreduce-client-jobclient</artifactId>
+      <scope>provided</scope>
+    </dependency>
+    <dependency>
+      <groupId>org.apache.hadoop</groupId>
+      <artifactId>hadoop-mapreduce-client-jobclient</artifactId>
+      <scope>test</scope>
+      <type>test-jar</type>
+    </dependency>
+    <dependency>
+      <groupId>org.apache.hadoop</groupId>
+      <artifactId>hadoop-common</artifactId>
+      <scope>provided</scope>
+    </dependency>
+    <dependency>
+      <groupId>org.apache.hadoop</groupId>
+      <artifactId>hadoop-hdfs</artifactId>
+      <scope>provided</scope>
+    </dependency>
+    <dependency>
+      <groupId>org.apache.hadoop</groupId>
+      <artifactId>hadoop-common</artifactId>
+      <scope>test</scope>
+      <type>test-jar</type>
+    </dependency>
+    <dependency>
+      <groupId>org.apache.hadoop</groupId>
+      <artifactId>hadoop-hdfs</artifactId>
+      <scope>test</scope>
+      <type>test-jar</type>
+    </dependency>
+    <dependency>
+      <groupId>org.apache.hadoop</groupId>
+      <artifactId>hadoop-yarn-server-tests</artifactId>
+      <type>test-jar</type>
+      <scope>test</scope>
+    </dependency>
+  </dependencies>
+
+  <build>
+    <plugins>
+      <plugin>
+        <groupId>org.apache.maven.plugins</groupId>
+        <artifactId>maven-antrun-plugin</artifactId>
+        <executions>
+          <execution>
+            <id>create-log-dir</id>
+            <phase>process-test-resources</phase>
+            <goals>
+              <goal>run</goal>
+            </goals>
+            <configuration>
+              <target>
+                <delete dir="${test.build.data}"/>
+                <mkdir dir="${test.build.data}"/>
+                <mkdir dir="${hadoop.log.dir}"/>
+              </target>
+            </configuration>
+          </execution>
+        </executions>
+      </plugin>
+      <plugin>
+        <groupId>org.apache.maven.plugins</groupId>
+        <artifactId>maven-jar-plugin</artifactId>
+       </plugin>
+    </plugins>
+  </build>
+</project>
+
diff --git a/hadoop-mapreduce-project/src/contrib/data_join/src/java/org/apache/hadoop/contrib/utils/join/ArrayListBackedIterator.java b/hadoop-tools/hadoop-datajoin/src/main/java/org/apache/hadoop/contrib/utils/join/ArrayListBackedIterator.java
similarity index 100%
rename from hadoop-mapreduce-project/src/contrib/data_join/src/java/org/apache/hadoop/contrib/utils/join/ArrayListBackedIterator.java
rename to hadoop-tools/hadoop-datajoin/src/main/java/org/apache/hadoop/contrib/utils/join/ArrayListBackedIterator.java
diff --git a/hadoop-mapreduce-project/src/contrib/data_join/src/java/org/apache/hadoop/contrib/utils/join/DataJoinJob.java b/hadoop-tools/hadoop-datajoin/src/main/java/org/apache/hadoop/contrib/utils/join/DataJoinJob.java
similarity index 100%
rename from hadoop-mapreduce-project/src/contrib/data_join/src/java/org/apache/hadoop/contrib/utils/join/DataJoinJob.java
rename to hadoop-tools/hadoop-datajoin/src/main/java/org/apache/hadoop/contrib/utils/join/DataJoinJob.java
diff --git a/hadoop-mapreduce-project/src/contrib/data_join/src/java/org/apache/hadoop/contrib/utils/join/DataJoinMapperBase.java b/hadoop-tools/hadoop-datajoin/src/main/java/org/apache/hadoop/contrib/utils/join/DataJoinMapperBase.java
similarity index 100%
rename from hadoop-mapreduce-project/src/contrib/data_join/src/java/org/apache/hadoop/contrib/utils/join/DataJoinMapperBase.java
rename to hadoop-tools/hadoop-datajoin/src/main/java/org/apache/hadoop/contrib/utils/join/DataJoinMapperBase.java
diff --git a/hadoop-mapreduce-project/src/contrib/data_join/src/java/org/apache/hadoop/contrib/utils/join/DataJoinReducerBase.java b/hadoop-tools/hadoop-datajoin/src/main/java/org/apache/hadoop/contrib/utils/join/DataJoinReducerBase.java
similarity index 100%
rename from hadoop-mapreduce-project/src/contrib/data_join/src/java/org/apache/hadoop/contrib/utils/join/DataJoinReducerBase.java
rename to hadoop-tools/hadoop-datajoin/src/main/java/org/apache/hadoop/contrib/utils/join/DataJoinReducerBase.java
diff --git a/hadoop-mapreduce-project/src/contrib/data_join/src/java/org/apache/hadoop/contrib/utils/join/JobBase.java b/hadoop-tools/hadoop-datajoin/src/main/java/org/apache/hadoop/contrib/utils/join/JobBase.java
similarity index 97%
rename from hadoop-mapreduce-project/src/contrib/data_join/src/java/org/apache/hadoop/contrib/utils/join/JobBase.java
rename to hadoop-tools/hadoop-datajoin/src/main/java/org/apache/hadoop/contrib/utils/join/JobBase.java
index dd34a4bb566..9ef21b3085e 100644
--- a/hadoop-mapreduce-project/src/contrib/data_join/src/java/org/apache/hadoop/contrib/utils/join/JobBase.java
+++ b/hadoop-tools/hadoop-datajoin/src/main/java/org/apache/hadoop/contrib/utils/join/JobBase.java
@@ -51,7 +51,7 @@ public abstract class JobBase implements Mapper, Reducer {
    *          the value for the counter
    */
   protected void setLongValue(Object name, long value) {
-    this.longCounters.put(name, new Long(value));
+    this.longCounters.put(name, Long.valueOf(value));
   }
 
   /**
@@ -100,9 +100,9 @@ public abstract class JobBase implements Mapper, Reducer {
     Long val = this.longCounters.get(name);
     Long retv = null;
     if (val == null) {
-      retv = new Long(inc);
+      retv = Long.valueOf(inc);
     } else {
-      retv = new Long(val.longValue() + inc);
+      retv = Long.valueOf(val.longValue() + inc);
     }
     this.longCounters.put(name, retv);
     return retv;
diff --git a/hadoop-mapreduce-project/src/contrib/data_join/src/java/org/apache/hadoop/contrib/utils/join/ResetableIterator.java b/hadoop-tools/hadoop-datajoin/src/main/java/org/apache/hadoop/contrib/utils/join/ResetableIterator.java
similarity index 100%
rename from hadoop-mapreduce-project/src/contrib/data_join/src/java/org/apache/hadoop/contrib/utils/join/ResetableIterator.java
rename to hadoop-tools/hadoop-datajoin/src/main/java/org/apache/hadoop/contrib/utils/join/ResetableIterator.java
diff --git a/hadoop-mapreduce-project/src/contrib/data_join/src/java/org/apache/hadoop/contrib/utils/join/TaggedMapOutput.java b/hadoop-tools/hadoop-datajoin/src/main/java/org/apache/hadoop/contrib/utils/join/TaggedMapOutput.java
similarity index 100%
rename from hadoop-mapreduce-project/src/contrib/data_join/src/java/org/apache/hadoop/contrib/utils/join/TaggedMapOutput.java
rename to hadoop-tools/hadoop-datajoin/src/main/java/org/apache/hadoop/contrib/utils/join/TaggedMapOutput.java
diff --git a/hadoop-mapreduce-project/src/contrib/data_join/src/examples/org/apache/hadoop/contrib/utils/join/README.txt b/hadoop-tools/hadoop-datajoin/src/test/java/README.txt
similarity index 100%
rename from hadoop-mapreduce-project/src/contrib/data_join/src/examples/org/apache/hadoop/contrib/utils/join/README.txt
rename to hadoop-tools/hadoop-datajoin/src/test/java/README.txt
diff --git a/hadoop-mapreduce-project/src/contrib/data_join/src/examples/org/apache/hadoop/contrib/utils/join/SampleDataJoinMapper.java b/hadoop-tools/hadoop-datajoin/src/test/java/SampleDataJoinMapper.java
similarity index 100%
rename from hadoop-mapreduce-project/src/contrib/data_join/src/examples/org/apache/hadoop/contrib/utils/join/SampleDataJoinMapper.java
rename to hadoop-tools/hadoop-datajoin/src/test/java/SampleDataJoinMapper.java
diff --git a/hadoop-mapreduce-project/src/contrib/data_join/src/examples/org/apache/hadoop/contrib/utils/join/SampleDataJoinReducer.java b/hadoop-tools/hadoop-datajoin/src/test/java/SampleDataJoinReducer.java
similarity index 100%
rename from hadoop-mapreduce-project/src/contrib/data_join/src/examples/org/apache/hadoop/contrib/utils/join/SampleDataJoinReducer.java
rename to hadoop-tools/hadoop-datajoin/src/test/java/SampleDataJoinReducer.java
diff --git a/hadoop-mapreduce-project/src/contrib/data_join/src/examples/org/apache/hadoop/contrib/utils/join/SampleTaggedMapOutput.java b/hadoop-tools/hadoop-datajoin/src/test/java/SampleTaggedMapOutput.java
similarity index 100%
rename from hadoop-mapreduce-project/src/contrib/data_join/src/examples/org/apache/hadoop/contrib/utils/join/SampleTaggedMapOutput.java
rename to hadoop-tools/hadoop-datajoin/src/test/java/SampleTaggedMapOutput.java
diff --git a/hadoop-mapreduce-project/src/contrib/data_join/src/test/org/apache/hadoop/contrib/utils/join/TestDataJoin.java b/hadoop-tools/hadoop-datajoin/src/test/java/org/apache/hadoop/contrib/utils/join/TestDataJoin.java
similarity index 98%
rename from hadoop-mapreduce-project/src/contrib/data_join/src/test/org/apache/hadoop/contrib/utils/join/TestDataJoin.java
rename to hadoop-tools/hadoop-datajoin/src/test/java/org/apache/hadoop/contrib/utils/join/TestDataJoin.java
index 1eab9593df8..37df5b002e6 100644
--- a/hadoop-mapreduce-project/src/contrib/data_join/src/test/org/apache/hadoop/contrib/utils/join/TestDataJoin.java
+++ b/hadoop-tools/hadoop-datajoin/src/test/java/org/apache/hadoop/contrib/utils/join/TestDataJoin.java
@@ -57,6 +57,7 @@ public class TestDataJoin extends TestCase {
   public void testDataJoin() throws Exception {
     final int srcs = 4;
     JobConf job = new JobConf();
+    job.setBoolean("mapreduce.fileoutputcommitter.marksuccessfuljobs", false);
     Path base = cluster.getFileSystem().makeQualified(new Path("/inner"));
     Path[] src = writeSimpleSrc(base, job, srcs);
     job.setInputFormat(SequenceFileInputFormat.class);
diff --git a/hadoop-tools/hadoop-tools-dist/pom.xml b/hadoop-tools/hadoop-tools-dist/pom.xml
index 43edf485a93..595e86344ae 100644
--- a/hadoop-tools/hadoop-tools-dist/pom.xml
+++ b/hadoop-tools/hadoop-tools-dist/pom.xml
@@ -52,6 +52,11 @@
       <artifactId>hadoop-rumen</artifactId>
       <scope>compile</scope>
     </dependency>
+    <dependency>
+      <groupId>org.apache.hadoop</groupId>
+      <artifactId>hadoop-datajoin</artifactId>
+      <scope>compile</scope>
+    </dependency>
     <dependency>
       <groupId>org.apache.hadoop</groupId>
       <artifactId>hadoop-extras</artifactId>
diff --git a/hadoop-tools/pom.xml b/hadoop-tools/pom.xml
index 28cf27feb8c..dbf08e18136 100644
--- a/hadoop-tools/pom.xml
+++ b/hadoop-tools/pom.xml
@@ -32,6 +32,7 @@
     <module>hadoop-distcp</module>
     <module>hadoop-archives</module>
     <module>hadoop-rumen</module>
+    <module>hadoop-datajoin</module>
     <module>hadoop-tools-dist</module>
     <module>hadoop-extras</module>
   </modules>