I have extracted this from the book called
Rhomobile Beginner's Guide
Abhishek Nalwaya
Published Jul 2011
on page 18
it says:
Add JAVA_HOME
and JAVA_HOME/bin
in your environment variable, PATH.
To add this in PATH click on Environment Variables in Advanced Tab of System Property.
Select Path in System variables and add JAVA_HOME
and JAVA_HOME/bin
to textbox and click Ok.
What should be the value?
It will let you and other applications run Java tools without having to type the whole path.
I disagree about adding JAVA_HOME; I only have JAVA_HOME/bin in my PATH.
Tomcat requires that JAVA_HOME be set properly in order to operate; so do some other Java EE app servers. (I believe WebLogic needs it.)