c.dispose();
vFile close() {    if (a == null) {	return this;		// already closed    }    c.f.dispose();		// dispose frame    c.i.flush();		// dispose backing image    a.dispose();		// dispose graphics contexts    b.dispose();    Vector v = c.wlist;		// list of windows sharing the canvas    for (int j = 0; j < v.size(); j++) {	vWindow win = (vWindow) v.elementAt(j);	win.a = null;		// mark each as closed	win.b = null;	win.c = null;    }    v.removeAllElements();    return this;}