如何在JLabel内容变更时同步修改对应的int变量？

我正在尝试实现当JLabel内容变更时，同步修改对应的int变量。曾尝试使用AtomicInteger，但仅能实现修改n1的需求。请问如何根据选中的JLabel来修改对应的正确int变量？目前有n1至n3三个变量，未来会扩展到30个。当前代码如下：

public class GUI {
    JLabel currentEditLabel = null;
    JFrame frame;
    int n1 = 6;
    int n2 = 5;
    int n3 = 8;

    GUI() {
        frame = new JFrame();//creating instance of JFrame
        JLabel l1 = new JLabel(Integer.toString(n1));
        JLabel l2 = new JLabel(Integer.toString(n2));
        JLabel l3 = new JLabel(Integer.toString(n3));
        JTextField t = new JTextField();

        l1.setBounds(40, 50, 100, 40);
        l2.setBounds(40, 100, 100, 40);
        l3.setBounds(40, 150, 100, 40);
        t.setBounds(20, 200, 100, 40);

        frame.add(l1);
        frame.add(l2);
        frame.add(l3);
        frame.add(t);

        t.addActionListener(new ActionListener() {
            @Override
            public void actionPerformed(ActionEvent e) {
                if (currentEditLabel != null) {
                    currentEditLabel.setText(t.getText());
                    AtomicInteger level = new AtomicInteger(Integer.parseInt(currentEditLabel.getText()));
                    n1 = level.intValue();
                    currentEditLabel = null;
                }
            }
        });

        addMouseListener(l1, t);
        addMouseListener(l2, t);
        addMouseListener(l3, t);

        frame.setSize(400, 500);//400 width and 500 height
        frame.setLayout(null);//using no layout managers
        frame.setVisible(true);//making the frame visible
    }

    private void addMouseListener(JLabel label, JTextField t) {
        label.addMouseListener(new MouseAdapter() {
            @Override
            public void mouseClicked(MouseEvent e) {
                currentEditLabel = (JLabel) e.getComponent();
                t.setText(currentEditLabel.getText());
            }
        });
    }

    public static void main(String[] args) {
        new GUI();
    }
}

核心问题在于独立的int变量无法和JLabel建立动态关联，要支持未来扩展到30个变量，需要把数值存储在可索引容器中，或给每个JLabel绑定对应的数值引用。以下是两种可行方案：

方案1：使用数组存储数值，绑定JLabel索引 #

把独立int变量换成数组，给每个JLabel标记对应数组索引，修改时根据索引更新数组值，适合大量扩展场景：

import javax.swing.*;
import java.awt.event.*;

public class GUI {
    JLabel currentEditLabel = null;
    // 用数组存储所有数值，替代独立变量n1/n2/n3
    int[] nums = {6, 5, 8};
    JFrame frame;

    GUI() {
        frame = new JFrame();
        JLabel l1 = createLabel(0); // 绑定数组索引0
        JLabel l2 = createLabel(1); // 绑定数组索引1
        JLabel l3 = createLabel(2); // 绑定数组索引2
        JTextField t = new JTextField();

        l1.setBounds(40, 50, 100, 40);
        l2.setBounds(40, 100, 100, 40);
        l3.setBounds(40, 150, 100, 40);
        t.setBounds(20, 200, 100, 40);

        frame.add(l1);
        frame.add(l2);
        frame.add(l3);
        frame.add(t);

        t.addActionListener(new ActionListener() {
            @Override
            public void actionPerformed(ActionEvent e) {
                if (currentEditLabel != null) {
                    int newValue = Integer.parseInt(t.getText());
                    currentEditLabel.setText(String.valueOf(newValue));
                    // 获取Label绑定的索引，更新数组对应位置的值
                    int index = (int) currentEditLabel.getClientProperty("numIndex");
                    nums[index] = newValue;
                    currentEditLabel = null;
                }
            }
        });

        addMouseListener(l1, t);
        addMouseListener(l2, t);
        addMouseListener(l3, t);

        frame.setSize(400, 500);
        frame.setLayout(null);
        frame.setVisible(true);
    }

    // 创建带索引绑定的Label
    private JLabel createLabel(int index) {
        JLabel label = new JLabel(String.valueOf(nums[index]));
        // 用ClientProperty存储索引，关联Label和数组位置
        label.putClientProperty("numIndex", index);
        return label;
    }

    private void addMouseListener(JLabel label, JTextField t) {
        label.addMouseListener(new MouseAdapter() {
            @Override
            public void mouseClicked(MouseEvent e) {
                currentEditLabel = (JLabel) e.getComponent();
                t.setText(currentEditLabel.getText());
            }
        });
    }

    public static void main(String[] args) {
        new GUI();
    }
}

方案2：自定义数值包装类，绑定JLabel和数值引用 #

因为int是基本类型无法直接引用传递，用自定义包装类存储数值，让每个JLabel绑定对应的包装实例，修改时直接更新包装类的值，适合需要单独访问某个变量的场景：

import javax.swing.*;
import java.awt.event.*;

// 自定义可修改的int包装类
class IntHolder {
    int value;
    IntHolder(int value) {
        this.value = value;
    }
}

public class GUI {
    // 记录当前选中Label对应的数值包装类
    IntHolder currentHolder = null;
    JLabel currentEditLabel = null;
    JFrame frame;
    // 每个变量对应一个IntHolder实例
    IntHolder n1 = new IntHolder(6);
    IntHolder n2 = new IntHolder(5);
    IntHolder n3 = new IntHolder(8);

    GUI() {
        frame = new JFrame();
        JLabel l1 = createLabel(n1);
        JLabel l2 = createLabel(n2);
        JLabel l3 = createLabel(n3);
        JTextField t = new JTextField();

        l1.setBounds(40, 50, 100, 40);
        l2.setBounds(40, 100, 100, 40);
        l3.setBounds(40, 150, 100, 40);
        t.setBounds(20, 200, 100, 40);

        frame.add(l1);
        frame.add(l2);
        frame.add(l3);
        frame.add(t);

        t.addActionListener(new ActionListener() {
            @Override
            public void actionPerformed(ActionEvent e) {
                if (currentEditLabel != null && currentHolder != null) {
                    int newValue = Integer.parseInt(t.getText());
                    currentEditLabel.setText(String.valueOf(newValue));
                    // 直接更新绑定的IntHolder的值
                    currentHolder.value = newValue;
                    currentEditLabel = null;
                    currentHolder = null;
                }
            }
        });

        addMouseListener(l1, t, n1);
        addMouseListener(l2, t, n2);
        addMouseListener(l3, t, n3);

        frame.setSize(400, 500);
        frame.setLayout(null);
        frame.setVisible(true);
    }

    private JLabel createLabel(IntHolder holder) {
        return new JLabel(String.valueOf(holder.value));
    }

    private void addMouseListener(JLabel label, JTextField t, IntHolder holder) {
        label.addMouseListener(new MouseAdapter() {
            @Override
            public void mouseClicked(MouseEvent e) {
                currentEditLabel = (JLabel) e.getComponent();
                currentHolder = holder;
                t.setText(currentEditLabel.getText());
            }
        });
    }

    public static void main(String[] args) {
        new GUI();
    }
}

方案对比 #

• 方案1适合未来大量扩展（如30个变量），只需扩展数组长度，循环创建Label即可，代码简洁易维护。
• 方案2保留了类似n1/n2的变量命名，适合需要单独访问某个变量的场景，但扩展到30个时会产生大量重复代码。

内容的提问来源于stack exchange，提问作者John Carlton