Problem about JAVA_HOME setting tip

Dear all!
Recently , I have read your paper I-TASSER .
Firstly ,congratulation to you for your distinguish work :I-TASSER ,then there are a problem when I try to installation the software I-TASSER.
Since you have recommended us the JAVA_HOME setting tip,when I enter the command "which java", I get /usr/bin/java. Then can I set the path /usr , it is OK? Should I have to use this kind of path /usr/java/latest
You know,in a Linux system,when we enter the command "which java",we usually get the execution path /usr/bin/java; then I have a question why the path you get is /usr/java/latest/bin/java in your machine.
Thanks!
wliu