Java For 循环无法访问的代码

Question

我的代码中有一个 for 循环，它在整个循环本身上给出错误，说它是 "unreachable code"。我完全不确定是什么导致了这个循环：

public ArrayList<Double> Update(ArrayList<Double> addInputs) 
{
// stores the resultant outputs from each layer

ArrayList<Double> outputs = null;

int cWeight = 0;

// first check that we have the correct amount of inputs

if (addInputs.size() != numInputs);
{
    // just return an empty vector if incorrect
    return outputs;
}

// For each layer....


for (int i = 0; i < numHiddenLayers + 1; ++i)
{
    if (i > 0)
    {
        addInputs = outputs;
    }

    outputs.clear();

    cWeight = 0;

    // for each neuron sum the (inputs * corresponding weights) .Throw

    // the total at our sigmoid function to get the output.

    for (int j = 0; j < neuronLayers.get(i).numNeurons; ++j)
    {
        double netinput = 0;

        int numberInputs = neuronLayers.get(i).listNeurons.get(j).numInputs;

    // for each weight

    for (int k = 0; k < numberInputs - 1; ++k)
    {
        // sum the weights x inputs

        netinput += neuronLayers.get(i).listNeurons.get(j).weights.get(k) *
                addInputs.get(cWeight++);
    }

    // add in the bias

    netinput += neuronLayers.get(i).listNeurons.get(j).weights.get(numberInputs - 1)
            *  dBias;

    // we can store the outputs from each layer as we generate them.

    // the combined activation is first filtered through the sigmoid

    //function

    outputs.add(sigmoid(netinput,dActivationResponse));
    }
}

它在

之后声明了整个for循环

// For each layer....

是无法访问的代码。任何帮助将不胜感激。

Answer 1

这里有一个分号，所以方法总是返回 outputs。删除它

if (addInputs.size() != numInputs); // <---- this one
{
    // just return an empty vector if incorrect
    return outputs;
}

Answer 2

你的 if:

末尾有一个分号

... != numInputs);

意味着它下面的 return 将总是发生，使得它下面的代码无法访问。

删除分号。

Answer 3

意思是因为if condition因为分号

而终止

因此 return 将始终执行哪个将控制权转移给调用者函数，从而跳过其余代码

Java For 循环无法访问的代码

Java For Loop Unreachable Code

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