Well you are going to have a heck of a time getting ANY answer unless you give us some hint about WHAT CLASS you want to know about the toString() method of. There are about 4 zillion classes that have that method, and the answer changes depending on the class.
However as an example:
int i = 1232354345;
String s = Integer.toString(i);
Now s has a string representation of the integer value.
So what class did YOU want to know about?