sentence: writeline ( sender + '' was changed '' ) ; -rcb- -rcb- class test -lcb- static void main ( ) -lcb- model m = new model ( ) ; new view1 ( m ) ; new view2 ( m ) ; m. change ( ) ; -rcb- -rcb- event handler in computer programming , an event handler is a callback subroutine that handles inputs received in a program ( called a listener in java and javascript ) .