When you have got multiple versions of Java installed, you can choose which one you want to use by running the update-alternatives command.
Running this command shows a list of installed Java JDKs and JREs allowing one to be selected as the default that is used when java needs to be executed.
$ 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-7-openjdk-amd64/jre/bin/java 1051 manual mode Press enter to keep the current choice[*], or type selection number: 2
To choose a default javac compiler, run the following command.
$ sudo update-alternatives --config javac
If you prefer to use a gui instead of the command line, you can execute galternatives instead and define the default versions of software with the following dialog.
$ sudo galternatives
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