JAVA_HOME variable under OSX... what is it exactly?

I've been trying to build evaldictator on OSX. Unfortunately I have litt开发者_如何学运维le to no idea of what ant or scons actually do.

My main question is when I do something like

export JAVA_HOME='/lab/speech/java/jdk1.5.0_06'

what am I doing.

Thanks in advance

You are telling ANT to use java executable at $JAVA_HOME/bin/java. This allows you to have many versions of JAVA installed in your system and you can pick a specific version.