rhomobile – Add JAVA_HOME and JAVA_HOME/bin in your environment variable
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.)
The value should be the install directory for your JRE or JDK,
Browse your program files folder for a java folder, should look something like:
There will be a directory called bin inside it.