java图形界面 计算器实现

编写程序实现一个简单计算器的基本功能，具体可以模仿Windows附件中的计算器或模拟常见的实物计算器。

package beizi;

import java.awt.EventQueue;

import javax.swing.JFrame;
import javax.script.ScriptEngine;
import javax.script.ScriptEngineManager;
import javax.swing.JButton;
import java.awt.event.ActionListener;
import java.awt.event.ActionEvent;
import javax.swing.JTextArea;
import javax.swing.JTextPane;
import javax.swing.JLabel;
import javax.swing.JOptionPane;

import java.awt.TextArea;
import java.awt.Color;
import javax.swing.JTextField;

public class cal {

	private JFrame frame;
	private JTextField textField;
	private JTextField textField_1;

	/**
	 * Launch the application.
	 */
	public static void main(String[] args) {
		EventQueue.invokeLater(new Runnable() {
			public void run() {
				try {
					cal window = new cal();
					window.frame.setVisible(true);
				} catch (Exception e) {
					e.printStackTrace();
				}
			}
		});
	}

	/**
	 * Create the application.
	 */
	public cal() {
		initialize();
//		calResult();
	}

	/**
	 * Initialize the contents of the frame.
	 */
 	private void initialize() {
		frame = new JFrame();
		frame.setBounds(100, 100, 450, 400);
		frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
		frame.getContentPane().setLayout(null);
		
		
		
		JButton btnNewButton = new JButton("1");
		btnNewButton.setBackground(Color.LIGHT_GRAY);
		btnNewButton.addActionListener(new ActionListener() {
			public void actionPerformed(ActionEvent arg0) {
				String text=textField.getText();
				textField.setText(text+"1");
			}
		});
		btnNewButton.setBounds(33, 142, 68, 38);
		frame.getContentPane().add(btnNewButton);

		JButton button = new JButton("4");
		button.addActionListener(new ActionListener() {
			public void actionPerformed(ActionEvent arg0) {
				String text=textField.getText();
				textField.setText(text+"4");
			}
		});
		button.setBackground(Color.LIGHT_GRAY);
		button.setBounds(33, 194, 68, 38);
		frame.getContentPane().add(button);

		JButton button_1 = new JButton("7");
		button_1.addActionListener(new ActionListener() {
			public void actionPerformed(ActionEvent arg0) {
				String text=textField.getText();
				textField.setText(text+"7");
			}
		});
		button_1.setBackground(Color.LIGHT_GRAY);
		button_1.setBounds(33, 242, 68, 38);
		frame.getContentPane().add(button_1);

		JButton button_2 = new JButton("2");
		button_2.addActionListener(new ActionListener() {
			public void actionPerformed(ActionEvent arg0) {
				String text=textField.getText();
				textField.setText(text+"2");
			}
		});
		button_2.setBackground(Color.LIGHT_GRAY);
		button_2.setBounds(111, 142, 68, 38);
		frame.getContentPane().add(button_2);
		
		JButton button_3 = new JButton("5");
		button_3.addActionListener(new ActionListener() {
			public void actionPerformed(ActionEvent arg0) {
				String text=textField.getText();
				textField.setText(text+"5");
			}
		});
		button_3.setBackground(Color.LIGHT_GRAY);
		button_3.setBounds(111, 194, 68, 38);
		frame.getContentPane().add(button_3);
		
		JButton button_4 = new JButton("8");
		button_4.addActionListener(new ActionListener() {
			public void actionPerformed(ActionEvent arg0) {
				String text=textField.getText();
				textField.setText(text+"8");
			}
		});
		button_4.setBackground(Color.LIGHT_GRAY);
		button_4.setBounds(111, 242, 68, 38);
		frame.getContentPane().add(button_4);
		
		JButton button_5 = new JButton("3");
		button_5.addActionListener(new ActionListener() {
			public void actionPerformed(ActionEvent arg0) {
				String text=textField.getText();
				textField.setText(text+"3");
			}
		});
		button_5.setBackground(Color.LIGHT_GRAY);
		button_5.setBounds(189, 142, 68, 38);
		frame.getContentPane().add(button_5);
		
		JButton button_6 = new JButton("6");
		button_6.addActionListener(new ActionListener() {
			public void actionPerformed(ActionEvent arg0) {
				String text=textField.getText();
				textField.setText(text+"6");
			}
		});
		button_6.setBackground(Color.LIGHT_GRAY);
		button_6.setBounds(189, 194, 68, 38);
		frame.getContentPane().add(button_6);
		
		JButton button_7 = new JButton("9");
		button_7.addActionListener(new ActionListener() {
			public void actionPerformed(ActionEvent arg0) {
				String text=textField.getText();
				textField.setText(text+"9");
			}
		});
		button_7.setBackground(Color.LIGHT_GRAY);
		button_7.setBounds(189, 242, 68, 38);
		frame.getContentPane().add(button_7);
		
		JButton button_8 = new JButton("0");
		button_8.addActionListener(new ActionListener() {
			public void actionPerformed(ActionEvent arg0) {
				String text=textField.getText();
				textField.setText(text+"0");
			}
		});
		button_8.setBackground(Color.LIGHT_GRAY);
		button_8.setBounds(111, 290, 68, 38);
		frame.getContentPane().add(button_8);
		
		JButton button_9 = new JButton("(");
		button_9.setBackground(Color.ORANGE);
		button_9.addActionListener(new ActionListener() {
			public void actionPerformed(ActionEvent arg0) {
				String text=textField.getText();
				textField.setText(text+"(");
			}
		});
		button_9.setBounds(33, 93, 68, 38);
		frame.getContentPane().add(button_9);
		
		JButton button_10 = new JButton(")");
		button_10.setBackground(Color.ORANGE);
		button_10.addActionListener(new ActionListener() {
			public void actionPerformed(ActionEvent arg0) {
				String text=textField.getText();
				textField.setText(text+")");
			}
		});
		button_10.setBounds(109, 94, 70, 38);
		frame.getContentPane().add(button_10);
		
		JButton button_11 = new JButton("+");
		button_11.setBackground(Color.ORANGE);
		button_11.addActionListener(new ActionListener() {
			public void actionPerformed(ActionEvent arg0) {
				String text=textField.getText();
				textField.setText(text+"+");
			}
		});
		button_11.setBounds(267, 142, 44, 38);
		frame.getContentPane().add(button_11);
		
		JButton button_12 = new JButton("-");
		button_12.setBackground(Color.ORANGE);
		button_12.addActionListener(new ActionListener() {
			public void actionPerformed(ActionEvent arg0) {
				String text=textField.getText();
				textField.setText(text+"-");
			}
		});
		button_12.setBounds(267, 194, 44, 38);
		frame.getContentPane().add(button_12);
		
		JButton button_13 = new JButton("*");
		button_13.setBackground(Color.ORANGE);
		button_13.addActionListener(new ActionListener() {
			public void actionPerformed(ActionEvent arg0) {
				String text=textField.getText();
				textField.setText(text+"*");
			}
		});
		button_13.setBounds(267, 242, 44, 38);
		frame.getContentPane().add(button_13);
		
		JButton button_14 = new JButton("/");
		button_14.setBackground(Color.ORANGE);
		button_14.addActionListener(new ActionListener() {
			public void actionPerformed(ActionEvent arg0) {
				String text=textField.getText();
				textField.setText(text+"/");
			}
		});
		button_14.setBounds(267, 290, 44, 38);
		frame.getContentPane().add(button_14);
		
		JButton button_15 = new JButton("=");
		button_15.setBackground(Color.GREEN);
		button_15.addActionListener(new ActionListener() {
			public void actionPerformed(ActionEvent arg0) {
				ScriptEngine js = new ScriptEngineManager().getEngineByName("JavaScript");//将字符串公式转换为计算公式
				String formula=textField.getText();
				try {
					textField_1.setText(js.eval(formula).toString());
//					textField_1.set
				}catch(Exception e) {
					
				}
			}
		});
		button_15.setBounds(334, 252, 44, 76);
		frame.getContentPane().add(button_15);

		textField = new JTextField();
		textField.setBounds(33, 21, 345, 37);
		frame.getContentPane().add(textField);
		textField.setColumns(10);

		textField_1 = new JTextField();
		textField_1.setBackground(Color.WHITE);
		textField_1.setBounds(189, 94, 189, 37);
		frame.getContentPane().add(textField_1);
		textField_1.setColumns(10);
		
		JButton button_16 = new JButton("C");
		button_16.setBackground(Color.MAGENTA);
		button_16.addActionListener(new ActionListener() {
			public void actionPerformed(ActionEvent arg0) {
				String text=textField.getText();
				int t=text.length()-1;
				if(t<0) {
					JOptionPane.showMessageDialog(null, "已经没有了((");
					
				}
				else {
					text=text.substring(0, t);
					textField.setText(text);
				}

			}
		});
		button_16.setBounds(334, 142, 44, 38);
		frame.getContentPane().add(button_16);
		
		JButton button_17 = new JButton("X");
		button_17.setBackground(Color.RED);
		button_17.addActionListener(new ActionListener() {
			public void actionPerformed(ActionEvent arg0) {
				textField.setText("");
				textField_1.setText("");
			}
		});
		button_17.setBounds(334, 202, 44, 38);
		frame.getContentPane().add(button_17);
		
		JButton button_18 = new JButton(".");
		button_18.addActionListener(new ActionListener() {
			public void actionPerformed(ActionEvent arg0) {
				String text=textField.getText();
				textField.setText(text+".");
			}
		});
		button_18.setBackground(Color.ORANGE);
		button_18.setBounds(33, 290, 68, 38);
		frame.getContentPane().add(button_18);
		
		JButton button_19 = new JButton("%");
		button_19.addActionListener(new ActionListener() {
			public void actionPerformed(ActionEvent arg0) {
				String text=textField.getText();
				textField.setText(text+"%");
			}
		});
		button_19.setBackground(Color.ORANGE);
		button_19.setBounds(189, 290, 68, 38);
		frame.getContentPane().add(button_19);
		
	}
}

大概的效果，Java初学者，，代码重复严重，以后改，，，