question: public synchronized void update ( ) { if ( frames . size ( ) > 1 ) { animTime += 1 ; if ( animTime >= totalDuration ) { animTime = animTime % totalDuration ; currFrameIndex = 0 ; } while ( animTime > getFrame ( currFrameIndex ) . endTime ) { currFrameIndex ++ ; } } }
target:  Updates this animation's current image (frame), if necessary.