用Java实现下面的要求：布局计算器：1、在顶部的显示标签，将用来显示计算结果/2、一个文本字段，供用户在中间输入整数或者二倍的文本字段3、在底部有“clear”，“+”，“-”，“*”和“/”的按钮。创建一个累加器状态变量，用以跟踪计算的当前总值。1、点击“清除”按钮，将累加器值设置为0/2、点击“+”按钮，将文本字段值添加到累加器值/3、点击“-”按钮，从累加器值中减去文本字段值/4、点击“*”按钮，将累加段值乘以/5、点击“/”按钮，将累加器值除以文本字段值6、按下CLR按钮后，用新的累加器值更新显示标签，清空文本字段。

以下是用Java实现布局计算器的代码：

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

public class Calculator extends JFrame implements ActionListener {

    private JLabel resultLabel;
    private JTextField inputField;
    private JButton clearButton;
    private JButton addButton;
    private JButton minusButton;
    private JButton multiplyButton;
    private JButton divideButton;
    private int accumulator;

    public Calculator() {
        setTitle("Calculator");
        setSize(300, 200);
        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        setLayout(new BorderLayout());

        // 创建顶部的显示标签
        resultLabel = new JLabel("0", JLabel.RIGHT);
        resultLabel.setFont(new Font("Arial", Font.PLAIN, 20));
        add(resultLabel, BorderLayout.NORTH);

        // 创建中间的文本字段
        inputField = new JTextField();
        inputField.setFont(new Font("Arial", Font.PLAIN, 20));
        add(inputField, BorderLayout.CENTER);

        // 创建底部的按钮
        JPanel buttonPanel = new JPanel(new GridLayout(1, 5, 5, 5));
        clearButton = new JButton("CLR");
        addButton = new JButton("+");
        minusButton = new JButton("-");
        multiplyButton = new JButton("*");
        divideButton = new JButton("/");
        clearButton.addActionListener(this);
        addButton.addActionListener(this);
        minusButton.addActionListener(this);
        multiplyButton.addActionListener(this);
        divideButton.addActionListener(this);
        buttonPanel.add(clearButton);
        buttonPanel.add(addButton);
        buttonPanel.add(minusButton);
        buttonPanel.add(multiplyButton);
        buttonPanel.add(divideButton);
        add(buttonPanel, BorderLayout.SOUTH);

        setVisible(true);
    }

    public void actionPerformed(ActionEvent e) {
        if (e.getSource() == clearButton) {
            accumulator = 0;
            resultLabel.setText("0");
            inputField.setText("");
        } else {
            int value;
            try {
                value = Integer.parseInt(inputField.getText());
            } catch (NumberFormatException ex) {
                value = 0;
            }
            if (e.getSource() == addButton) {
                accumulator += value;
            } else if (e.getSource() == minusButton) {
                accumulator -= value;
            } else if (e.getSource() == multiplyButton) {
                accumulator *= value;
            } else if (e.getSource() == divideButton) {
                if (value == 0) {
                    JOptionPane.showMessageDialog(this, "除数不能为0！", "错误", JOptionPane.ERROR_MESSAGE);
                    return;
                }
                accumulator /= value;
            }
            resultLabel.setText(String.valueOf(accumulator));
            inputField.setText("");
        }
    }

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

运行该程序后，即可看到一个简单的布局计算器界面。用户可以在中间的文本字段中输入整数或者二进制数，然后点击底部的“+”、“-”、“*”、“/”按钮进行计算。点击“CLR”按钮可以清空输入和计算结果。