code to mouse click a particular cordinate in JPANEL

You cannot click anything "automatically": the click is the operation on a hardware (mouse or any other device functioning like a mouse), and nothing else.

Apparently you need something different. Most likely, you just need some method with exact same effect as the physical click on mouse. If this is so, you should do exactly this. Write some function. Add a handler of the mouse click. In this handler, all you need to do is to call this function. After this is done, the call of this function will have the same effect as the click.

As simple as that.

—SA