Java classpath - Linux

Question

I am trying to understand how classpath really works. After searching around the web this is where I have reached so far:

I have added

export CLASSP         


        

Answer 1

When you remove

export CLASSPATH="/home/foo:/home/foo/Java_code/my_code"

line and then source ... it wouldn't remove the CLASSPATH because it has already been set. It doesn't clear the variables which have already been defined.