collector.foundNullDeref(new Location(exceptionThrowerHandle, basicBlock), valueNumber, refValue);
collector.foundNullDeref(new Location(exceptionThrowerHandle, basicBlock), valueNumber, refValue, vnaFrame);
	private void analyzeNullCheck(ClassContext classContext, Method method, IsNullValueDataflow invDataflow,            BasicBlock basicBlock)		throws DataflowAnalysisException, CFGBuilderException {		// Look for null checks where the value checked is definitely		// null or null on some path.				InstructionHandle exceptionThrowerHandle = basicBlock.getExceptionThrower();		Instruction exceptionThrower = exceptionThrowerHandle.getInstruction();				// Get the stack values at entry to the null check.		IsNullValueFrame frame = invDataflow.getStartFact(basicBlock);		if (!frame.isValid())			return;				// Could the reference be null?		IsNullValue refValue = frame.getInstance(exceptionThrower, classContext.getConstantPoolGen());		if (!refValue.mightBeNull())			return;				// Get the value number		ValueNumberFrame vnaFrame = classContext.getValueNumberDataflow(method).getStartFact(basicBlock);		if (!vnaFrame.isValid())			return;		ValueNumber valueNumber = vnaFrame.getInstance(exceptionThrower, classContext.getConstantPoolGen());				// Issue a warning		collector.foundNullDeref(new Location(exceptionThrowerHandle, basicBlock), valueNumber, refValue);	}