if (frame == null || frame.getTopValue().isNotThis())
if (frame == null || !isThisValue(frame.getTopValue()))
	public int getDelta(Instruction ins, ThisValueFrame frame) throws DataflowAnalysisException  {		int delta = 0;		if (ins instanceof MONITORENTER) {			if (frame == null || frame.getTopValue().isNotThis())				++delta;		} else if (ins instanceof MONITOREXIT) {			if (frame == null || frame.getTopValue().isNotThis())				--delta;		}		return delta;	}