question: public void exit ( Object monitor ) { if ( monitor == null ) { throw new NullPointerException ( ) ; } ListIterator it = monitors . listIterator ( monitors . size ( ) ) ; while ( it . hasPrevious ( ) ) { Object prev = it . previous ( ) ; if ( monitor == prev ) { it . remove ( ) ; return ; } } throw new IllegalArgumentException ( ) ; }
target:  Do not use -- for internal use only. <p> Should be called after a MONITOREXIT instruction has been executed. Untracks the object that MONITOREXIT was used on.