Change Maven JDK

Sometimes you want Maven to compile your code with a different JDK than is the one assigned to your JAVA_HOME. For instance, I have code in a project that I'm working on that only compiles on Java 1.5. My JAVA_HOME, however, is 1.6. So, how do we specify the JDK for Maven?

Go to the pom.xml for the module or submodule that needs a specific JDK version for compilation, and insert such a goody:

<project>
   <build>
      <plugins>
         <plugin>
         <artifactId>maven-compiler-plugin</artifactId>
            <configuration>
               <source>1.5</source>
               <target>1.5</target>
               <compilerVersion>1.5</compilerVersion>               
               <executable>/usr/lib/jvm/java-1.5.0-sun/bin/javac</executable>
            </configuration>
         </plugin>
      </plugins>
   </build>
</project>

Note: My code parser/colorer is removing camelcase, which is important. (ie, artifactId, compilerVersion)

Notice that the executable for javac is hardcoded in the pom.xml. That's not the most awesome thing to do, so you can use a property for the absolute path that can be specified on a per-user basis. For more details, see the Apache documentation.

Now mvn compile, etc, and JDK 1.5 will be used where you have specified.