calling Java code from Firefox extension

Hi all,

I'm new to firefox extension. I want to calling Java code from within a
Firefox extension,

I can using liveconnect and xpconnect to do it ,

I'm just want to know what's different about it and JAVAXPCOM.

If I using javaxpcom , am I need to via JNI to complete ?

 

Again, any help here would be seriously appreciated.  Even if it's

just a little insight.