java - Can you hook into an interface-less jar? -

is possible run function upon function call in interface-less import?if i'm importing library, example, possible each time function foo called, function, bar, called well? thanks

if can edit code , class foo resides in non-final, can override class's foo call bar well:

class myfooclass extends fooclass{     @override     void foo(){         bar(); //not sure if want bar static or not, or if want bar first or last.         super.foo();      } } 

then use myfooclass instead of fooclass throughout code.