calculatorpanel.java

java test大学本科java试验全部代码

package calculator;

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

public class CalculatorPanel extends JPanel implements Runnable{
   
    private JTextField timeDisplay;//显示时间
    private JTextField display;//显示计算结果
    private JPanel panel;
    private JPanel textPanel;
    
    private double result;
    private String lastCommand;
    private boolean start;
    
    private Thread showTime = null;
    	
	public CalculatorPanel()
	{
		showTime = new Thread(this);
		try
		{
			showTime.start();
		}
		catch(Exception e)
		{
			e.printStackTrace();
		}
		
		setLayout(new BorderLayout());
		
		result      = 0.0;
		lastCommand = "=";
		start       = true;
		
		//显示部分
		timeDisplay = new JTextField("");
		timeDisplay.setEditable(false);
		//add(timeDisplay,BorderLayout.NORTH);
			
		display = new JTextField("0");
		display.setEditable(false);
		//add(display,BorderLayout.CENTER);
		
		textPanel = new JPanel();
		textPanel.setLayout(new GridLayout(2,1));
		textPanel.add(timeDisplay);
		textPanel.add(display);
		add(textPanel,BorderLayout.NORTH);
		
		ActionListener insert = new InsertAction();
		ActionListener command = new CommandAction();
		
		//加按钮
		panel = new JPanel();
		panel.setLayout(new GridLayout(4,4));
		
		addButton("7",insert);
		addButton("8",insert);
		addButton("9",insert);
		addButton("/",command);
		
		addButton("4",insert);
		addButton("5",insert);
		addButton("6",insert);
		addButton("*",command);
		
		addButton("1",insert);
		addButton("2",insert);
		addButton("3",insert);
		addButton("-",command);
		
		addButton("0",insert);
		addButton(".",insert);
		addButton("=",command);
		addButton("+",command);
		
		add(panel,BorderLayout.CENTER);
		//add(panel,BorderLayout.SOUTH);
	}
	
	private void addButton(String label,ActionListener listener)
	{
		JButton button = new JButton(label);
		button.addActionListener(listener);
		panel.add(button);
	}
	
	private class InsertAction implements ActionListener
	{
		public void actionPerformed(ActionEvent event)
		{
			String input = event.getActionCommand();
			if(start)
			{
				display.setText("");
				start = false;
			}
			display.setText(display.getText()+input);
		}
	}
	
	private class CommandAction implements ActionListener
	{
		public void actionPerformed(ActionEvent event)
		{
			String command = event.getActionCommand();
			if(start)
			{
				if(command.equals("-"))
				{
					display.setText((command));
					start = false;
				}
				else{
					lastCommand = command;
				}
			}
			else
			{
				calculate(Double.parseDouble(display.getText()));
				lastCommand = command;
				start = true;
			}
		}
	}
	
	public void calculate(double x)
	{
		if(lastCommand.equals("+")) result += x;
		else if(lastCommand.equals("-")) result -=x;
		else if(lastCommand.equals("*")) result *=x;
		else if(lastCommand.equals("/")) result /=x;
		else if(lastCommand.equals("=")) result =x;
		display.setText(" "+result);
	}
	
	public void run()
	{
		while(true)
		{
			Date timeNow = new Date();
			SimpleDateFormat format = new SimpleDateFormat("yyyy年MM月Edd日HH时mm分ss秒");
			String show = format.format(timeNow);
			timeDisplay.setText(show);	
		}
	}
}