mycalculator.java

JAVA计算机器源代码！我的呕心沥血之作！

//MyCalculator.java

import java.awt.*; //包含用于创建用户界面和绘制图形图像的所有类
import java.awt.event.*; //提供处理由 AWT 组件所激发的各类事件的接口和类
import javax.swing.*;

//ActionListener用于接收操作事件的侦听器接口
public class MyCalculator extends JFrame implements ActionListener {
	MyCalculator frame;

	JTextField answer = new JTextField("0.");

	JPanel panel = new JPanel();

	JPanel pane2 = new JPanel();

	String left = "";

	String right = "";

	String mid = "";

	char flag = '\0';

	boolean pit = true;

	Container container = getContentPane();

	// pane2上的控制按钮
	JButton clear = new JButton("清零");

	JButton button0 = new JButton("0");

	JButton button1 = new JButton("1");

	JButton button2 = new JButton("2");

	JButton button3 = new JButton("3");

	JButton button4 = new JButton("4");

	JButton button5 = new JButton("5");

	JButton button6 = new JButton("6");

	JButton button7 = new JButton("7");

	JButton button8 = new JButton("8");

	JButton button9 = new JButton("9");

	JButton sum = new JButton("+");

	JButton sub = new JButton("-");

	JButton mul = new JButton("×");

	JButton div = new JButton("÷");

	JButton point = new JButton(".");

	JButton equal = new JButton("=");

	JButton cos = new JButton("cos()");

	JButton sin = new JButton("sin()");

	JButton sqr = new JButton("sqrt");

	JButton back = new JButton("退格");

	public MyCalculator() { // 构造函数
		super("简易计算器");

		panel.setLayout(new BorderLayout()); // panel 的布局方式
		pane2.setLayout(new GridLayout(5, 4,3,3)); // pane2 的布局方式

		clear.addActionListener(this);
		button1.addActionListener(this);
		button2.addActionListener(this);
		button3.addActionListener(this);
		button4.addActionListener(this);
		button5.addActionListener(this);
		button6.addActionListener(this);
		button7.addActionListener(this);
		button8.addActionListener(this);
		button9.addActionListener(this);
		button0.addActionListener(this);
		sum.addActionListener(this);
		sub.addActionListener(this);
		point.addActionListener(this);
		equal.addActionListener(this);
		cos.addActionListener(this);
		sin.addActionListener(this);
		div.addActionListener(this);
		mul.addActionListener(this);
		back.addActionListener(this);
		sqr.addActionListener(this);

		pane2.add(cos);
		pane2.add(sin);
		pane2.add(sqr);
		pane2.add(back);
		pane2.add(button1);
		pane2.add(button2);
		pane2.add(button3);
		pane2.add(sum);
		pane2.add(button4);
		pane2.add(button5);
		pane2.add(button6);
		pane2.add(sub);
		pane2.add(button7);
		pane2.add(button8);
		pane2.add(button9);
		pane2.add(mul);
		pane2.add(button0);
		pane2.add(point);
		pane2.add(equal);
		pane2.add(div);

		answer.setHorizontalAlignment(JTextField.RIGHT); // 设置文本的水平对齐方式
		answer.setColumns(2); // 设置此 TextField 中的列数，然后验证布局
		// 设置指定的 boolean 变量，以指示此 TextComponent 是否应该为可编辑
		answer.setEditable(false);
		answer.setBackground(Color.LIGHT_GRAY);

		Font ft = new Font(null, Font.PLAIN, 20); //根据指定名称、样式和磅值大小，创建一个新 Font
		answer.setFont(ft);   // 设置当前字体

		panel.add(clear, BorderLayout.NORTH);
		panel.add(pane2, BorderLayout.CENTER);
		
		container.add(answer, BorderLayout.NORTH);
		container.add(panel, BorderLayout.CENTER);
		
		WindowListener wl = new WindowAdapter() {
			public void windowClosing(WindowEvent e) {
				MyCalculator.this.dispose();
				System.exit(0);
			}
		};
		
		this.addWindowListener(wl);

		this.setSize(300, 280);
		//this.setBackground(Color.red);
		this.setVisible(true);
	}

	// 进行算术的运算
	public void actionPerformed(ActionEvent e) {

		if (e.getSource() == button1) { // getSource()返回最初发生 Event 的对象
			mid = mid + "1";
			answer.setText(mid); // setText()将此 TextComponent 文本设置为指定文本
		}
		if (e.getSource() == button2) {
			mid = mid + "2";
			answer.setText(mid);
		}
		if (e.getSource() == button3) {
			mid = mid + "3";
			answer.setText(mid);
		}
		if (e.getSource() == button4) {
			mid = mid + "4";
			answer.setText(mid);
		}
		if (e.getSource() == button5) {
			mid = mid + "5";
			answer.setText(mid);
		}
		if (e.getSource() == button6) {
			mid = mid + "6";
			answer.setText(mid);
		}
		if (e.getSource() == button7) {
			mid = mid + "7";
			answer.setText(mid);
		}
		if (e.getSource() == button8) {
			mid = mid + "8";
			answer.setText(mid);
		}
		if (e.getSource() == button9) {
			mid = mid + "9";
			answer.setText(mid);
		}
		if (e.getSource() == button0) {
			mid = mid + "0";
			answer.setText(mid);
		}
		if (e.getSource() == point) { // 实现 “.”
			String chk = answer.getText();
			if (!chk.equals("0.")) {
				if (pit && answer.getText().length() != 0) {
					mid = mid + ".";
					answer.setText(mid);
					pit = false;
				}
			}
		}
		if (e.getSource() == back) { //
			if (answer.getText().length() != 0) {
				int len = answer.getText().length();
				mid = answer.getText().substring(0, len - 1);
				answer.setText(mid);
			}
			int g = mid.indexOf(".");
			if (g == -1) {
				pit = true;
			}
		}
		if (e.getSource() == clear) {
			mid = "";
			answer.setText("0.");
		}
		if (e.getSource() == sum) {
			flag = '+';
			pit = true;
			left = answer.getText();
			mid = "";
			answer.setText("");
		}
		if (e.getSource() == sub) {
			String chk = answer.getText().trim();
			if (chk.equals("") || chk.equals("0.")) {
				mid = mid + "-";
				answer.setText(mid);
			} else {
				flag = '-';
				pit = true;
				left = answer.getText();
				mid = "";
				answer.setText("");
			}
		}
		if (e.getSource() == mul) {
			flag = '×';
			pit = true;
			left = answer.getText();
			mid = "";
			answer.setText("");
		}
		if (e.getSource() == div) {
			flag = '÷';
			pit = true;
			left = answer.getText();
			mid = "";
			answer.setText("");
		}
		try {
			if (e.getSource() == sqr) {
				double res1 = 0;
				if (!answer.getText().equals("")) {
					double sq = Double.parseDouble(answer.getText());
					if (sq >= 0) {
						res1 = Math.sqrt(sq);
						answer.setText(String.valueOf(res1));
					} else {
						answer.setText("0");
					}
				}
			}
			if (e.getSource() == cos) {
				if (!answer.getText().equals("")) {
					double res2 = Math
							.cos(Double.parseDouble(answer.getText()));
					answer.setText(String.valueOf(res2));
				}
			}
			if (e.getSource() == sin) {
				if (!answer.getText().equals("")) {
					double res2 = Math
							.sin(Double.parseDouble(answer.getText()));
					answer.setText(String.valueOf(res2));
				}
			}
		} catch (NumberFormatException ex) {
			System.out.println("出现了对非数字计算问题!");
		}
		if (e.getSource() == equal) {
			double res = 0;
			mid = "";
			if (!left.equals("") && !answer.getText().equals("")) {
				try {
					switch (flag) {
					case '+':
						right = answer.getText();
						res = Double.parseDouble(left)
								+ Double.parseDouble(right);
						answer.setText(String.valueOf(res));
						break;
					case '-':
						right = answer.getText();
						res = Double.parseDouble(left)
								- Double.parseDouble(right);
						answer.setText(String.valueOf(res));
						break;
					case '×':
						right = answer.getText();
						res = Double.parseDouble(left)
								* Double.parseDouble(right);
						answer.setText(String.valueOf(res));
						break;
					case '÷':
						right = answer.getText();
						if (Double.parseDouble(right) != 0) {
							res = Double.parseDouble(left)
									/ Double.parseDouble(right);
							answer.setText(String.valueOf(res));
						} else {
							JOptionPane.showMessageDialog(null, "除数不能为零,请改正!",
									"错误提示", JOptionPane.INFORMATION_MESSAGE);
							left = "";
						}
						break;
					}
				} catch (NumberFormatException ex) {
					System.out.println("出现了输入的异常");
				} catch (RuntimeException ex) {
					System.out.println("运行过程中出现异常");
				}
			}
		}
	}

	public static void main(String args[]) {
		MyCalculator application = new MyCalculator();

		application.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
	}
}