在Java中使用具有相同标签的多个JButton

我的项目中有两个带有 +标签的按钮。调用actionPerformed（）方法时，它将基于标签调用特定的方法。如何区分带有相同标签的两个JButton？

I have two buttons in my project that both have a "+" label. When the actionPerformed() method is called, it calls a specific method based on the label. How can I distiguish between two JButtons with the same label? Is there a better way to do this then how I've done it?

这是按钮的定义：

JButton keypadPlus1 = new JButton(" + ");
JButton keypadMinus1 = new JButton(" - ");
JButton keypadPlus2 = new JButton("+");
JButton keypadMinus2 = new JButton("-");

为按钮添加ActionListener：

Adding the ActionListeners for the buttons:

keypadPlus1.addActionListener(backEnd);
keypadPlus2.addActionListener(backEnd);
keypadMinus1.addActionListener(backEnd);
keypadMinus2.addActionListener(backEnd);

该操作在后端执行@Override：

The actionPerformed @Override in the backEnd:

public void actionPerformed (ActionEvent event) {
        String command = event.getActionCommand();
        if (command.equals("+")) {
            calcLifePoints(command);
        }
        if (command.equals("-")) {
            calcLifePoints(command);
        }
        if (command.equals(" + ")) {
            calcLifePoints(command);
        }
        if (command.equals(" - ")) {
            calcLifePoints(command);
        }

    }