public BindingSet match(InstructionHandle handle, ConstantPoolGen cpg,
public MatchResult match(InstructionHandle handle, ConstantPoolGen cpg,
	public BindingSet match(InstructionHandle handle, ConstantPoolGen cpg,		ValueNumberFrame before, ValueNumberFrame after, BindingSet bindingSet) throws DataflowAnalysisException {		// Instruction must be MONITORENTER.		Instruction ins = handle.getInstruction();		if (!(ins instanceof MONITORENTER))			return null;		// Ensure the object being locked matches any previous		// instructions which bound our variable name to a value.		Variable lock = new LocalVariable(before.getTopValue());		return addOrCheckDefinition(lock, bindingSet);	}