Switching JDK in Ubuntu

I have two JDK installed: OpenJDK and Sun version. There is one quick method to switch between them:

$sudo update-alternatives --config java

There are 2 choices for the alternative java (providing /usr/bin/java).

Selection Path Priority Status
------------------------------------------------------------
0 /usr/lib/jvm/java-6-openjdk/jre/bin/java 1061 auto mode
1 /usr/lib/jvm/java-6-openjdk/jre/bin/java 1061 manual mode
* 2 /usr/lib/jvm/java-6-sun/jre/bin/java 63 manual mode

Press enter to keep the current choice[*], or type selection number:

After selection you can check:
$ java -version