java 写一个计算机程序 java计算机程序代码

1.加法器（该java源文件的名称是Adder.java）

import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
 
public class Adder implements ActionListener
{
       JFrame AdderFrame;
       JTextField TOprand1;
       JTextField TOprand2;
       JLabel LAdd,LSum;
       JButton BAdd,BClear;
       JPanel JP1,JP2;
       public Adder()
       {
              AdderFrame=new JFrame("AdderFrame");
              TOprand1=new JTextField("0.0");
              TOprand2=new JTextField("0.0");
              LAdd=new JLabel("+");
              LSum=new JLabel("=   ");
              BAdd=new JButton("Add");
              BClear=new JButton("Clear");
              JP1=new JPanel();
              JP2=new JPanel();
              BAdd.addActionListener(this);
              BClear.addActionListener(new ActionListener()
              {
                     public void actionPerformed(ActionEvent event)
                     {
                            TOprand1.setText("0.0");
                            TOprand2.setText("0.0");
                            LSum.setText("=");      
                     }
              });
              AdderFrame.add(JP1);
              JP1.add(TOprand1);
              JP1.add(LAdd);
              JP1.add(TOprand2);
              JP1.add(LSum);
             
             
              AdderFrame.add(JP2);
              JP2.add(BAdd);
              JP2.add(BClear);
              AdderFrame.getContentPane().setLayout(new BorderLayout());
              AdderFrame.getContentPane().add(JP1,BorderLayout.NORTH);
              AdderFrame.getContentPane().add(JP2,BorderLayout.SOUTH);
             
              AdderFrame.addWindowListener(new WindowAdapter()
              {
                     public void windowClosing(WindowEvent event)
                     {
                            System.exit(0);
                     }
              });
              AdderFrame.pack();
              AdderFrame.setVisible(true);
              AdderFrame.setResizable(false);
              AdderFrame.setSize(250,100);
       }
       public void actionPerformed(ActionEvent event)
       {
                    
              double sum=(double)(Double.valueOf(TOprand1.getText()).doubleValue()+Double.valueOf(TOprand2.getText()).doubleValue());
              LSum.setText("="+sum);
       }
      
       public static void main(String[] args)
       {
              Adder adder=new Adder();
       }
}

 

 

2.小型记事本（该java源文件由两个类构成，名称为Notepad.java）

import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import java.io.*;
 
class mynotepad extends JFrame
{
    File file=null;
     Color color=Color.red;
     mynotepad()
     {
           initTextContent();
            initMenu();
            initAboutDialog();
     }
    
     void initTextContent()
     {
            getContentPane().add(new JScrollPane(content));
     }
   
    JTextPane content=new JTextPane();
    JFileChooser openfile=new JFileChooser();
    JColorChooser opencolor=new JColorChooser();
    JDialog about=new JDialog(this);
    JMenuBar menu=new JMenuBar();
     //菜单栏的各个菜单项
       JMenu[] menus=new JMenu[]{new JMenu("文件"),new JMenu("编辑"),new JMenu("关于")};
   
    //"文件"菜单项的四个下拉菜单
    //编辑菜单的四个下拉菜单
   
       JMenuItem optionofmenu[][]=new JMenuItem[][]{{new JMenuItem("新建"),new JMenuItem("打开"),new JMenuItem("保存"),new JMenuItem("退出")},
                                                                  {new JMenuItem("复制"),new JMenuItem("剪切"),new JMenuItem("粘贴"),new JMenuItem("颜色")},
                                                                               {new JMenuItem("关于")}
                                                                                };
     void initMenu()
    {
          for(int i=0;i<menus.length;i++)
          {
                menu.add(menus[i]);
                for(int j=0;j<optionofmenu[i].length;j++)
                {
                       menus[i].add(optionofmenu[i][j]);
                       optionofmenu[i][j].addActionListener( action );
                }
          }
          this.setJMenuBar(menu);
    }
   
    ActionListener action=new ActionListener()
    {                   //添加事件监听
           public void actionPerformed(ActionEvent e)
           {
                 String name = e.getActionCommand();
                     JMenuItem MI=(JMenuItem)e.getSource();
                     if("新建".equals(name))
                     {
                            content.setText("");
                            file=null;
                     }
                     else if("打开".equals(name))
                     {
                   if(file !=null)
                          openfile.setSelectedFile(file);
                int returnVal=openfile.showOpenDialog(mynotepad.this);
                if(returnVal==JFileChooser.APPROVE_OPTION)
                {
                                   file=openfile.getSelectedFile();
                    unfold();
                }
 
                 }
                 else if("保存".equals(name))
                 {
                        if(file!=null) openfile.setSelectedFile(file);
                     int returnVal=openfile.showSaveDialog(mynotepad.this);
                if(returnVal==JFileChooser.APPROVE_OPTION)
                {
                       file=openfile.getSelectedFile();
                      saving();
                }
          
            }
            else if("退出".equals(name))
            {
                   mynotepad f=new mynotepad();
                   int s=JOptionPane.showConfirmDialog(f,"退出？","退出",JOptionPane.YES_NO_OPTION);
                if(s==JOptionPane.YES_OPTION)
                System.exit(0);
            }
            else if("剪切".equals(name))
            {
                   content.cut();
            }
            else if("复制".equals(name))
            {
                   content.copy();
            }
            else if("粘贴".equals(name))
            {
                   content.paste();
            }
            else if("颜色".equals(name))
            {
                   color=JColorChooser.showDialog(mynotepad.this,"",color);
                content.setForeground(color);
                
                  }
                  else if("关于".equals(name))
                  {
              about.setSize(300,150);
              about.show();
                 }
   
            }
      };
     
      void saving()
      {
           try
           {
               FileWriter Writef=new FileWriter(file);
               Writef.write(content.getText());
               Writef.close();
        }
           catch(Exception e)
           {
                  e.printStackTrace();
           }
 
    }               
     
      void unfold()
      {
           try
           {
               FileReader Readf=new FileReader(file);
              int len=(int)file.length();
             char []buffer=new char[len];
              Readf.read(buffer,0,len);
            Readf.close();
            content.setText(new String(buffer));
        }
        catch(Exception e)
        {
               e.printStackTrace();
        }
       }
 
      void initAboutDialog()
      {
          about.setLayout(new GridLayout(3,1));
          about.getContentPane().setBackground(Color.white);
          about.getContentPane().add(new JLabel("我的记事本程序"));//对话框内容
          about.getContentPane().add(new JLabel("制作者：Fwx"));
          about.getContentPane().add(new JLabel("2007年12月"));
          about.setModal(true);                        //设置对话框前端显示
          about.setSize(100,100);                       
          about.setLocation(250,170);                  //设置对话框显示位置
    };
}  
 
public class Notepad
{
       public static void main(String args[])
       {                          //入口main函数
              mynotepad noted=new mynotepad();
        noted.addWindowListener(new WindowAdapter()
        {
       
        });
        noted.setTitle("我的记事本程序");           //记事本标题
              noted.setSize(640,320);                  //设置记事本大小
              noted.show();                        
              noted.setLocation(150,100);              //设置记事本显示位置
       }

}