采用Java Swing开发的一个定时关机的小工具源码

import java.awt.*;  import java.awt.event.*;  import java.io.IOException;  import java.util.Calendar;  import javax.swing.*;    public class CloseComputer extends JFrame implements ActionListener{   //创建成员变量   //创建实现BorderLayout布局的面板对象panelmain,用于放panelSubnorth面板和panelSubcenter面板   private JPanel panelMain;   //创建实现FlowLayout布局的面板对象panelSubnorth,用于放tag提示标签   private JPanel panelSubnorth;   //创建实现FlowLayout布局的面板对象panelSubcenter,用于放3个按钮   private JPanel panelSubcenter;     //创建三个按钮   private Button countdown;   private Button time;   private Button cancel;   private String key;   //创建一个提示标签   private JLabel tag;       public CloseComputer(){    initComponents();   }     /**    * 初始化组件信息    */   public void initComponents() {      panelMain=new JPanel(new BorderLayout(5, 10));      panelSubnorth=new JPanel(new FlowLayout(3));    panelSubcenter=new JPanel(new FlowLayout(1,5,5));      countdown=new Button("倒计时关机");    time=new Button("定时关机");    cancel=new Button("取消关机");      tag=new JLabel("请选择关机方式");      //将panelMain添加到窗体中    this.getContentPane().add(panelMain);    //添加对象panelSubnorth到对象panelMain窗口里    panelMain.add(panelSubnorth, BorderLayout.NORTH);    //添加对象panelSubcenter到对象panelMain窗口里    panelMain.add(panelSubcenter, BorderLayout.CENTER);      //添加标签对象tag到对象panelSubnorth窗口里    panelSubnorth.add(tag);      //添加3个按钮到对象panelSubcenter里    panelSubcenter.add(countdown);    panelSubcenter.add(time);    panelSubcenter.add(cancel);      //为3个按钮注册事件监听器    countdown.addActionListener(this);    time.addActionListener(this);    cancel.addActionListener(this);      this.setDefaultCloseOperation(EXIT_ON_CLOSE);    this.setResizable(false);    this.setLocation(350, 350);    this.setSize(400, 400);    this.setTitle("关机工具");      this.pack();   }     /**    * 倒计时关机    */   public void countdown() {    //创建字符串面板对象    key=JOptionPane.showInputDialog(this,"请输入倒计时关机剩余的时间(秒)","输入框",1);    try {     Runtime.getRuntime().exec("shutdown -s -t "+key);    } catch (IOException e) {     // TODO Auto-generated catch block     e.printStackTrace();    }   }   /**    * 定时关机    */   public void time(){    //获取当前系统的时间    Calendar calendar=Calendar.getInstance();    int h=calendar.get(Calendar.HOUR);  //获取小时    System.out.println(h);    int m=calendar.get(Calendar.MINUTE); //获取分钟    int s=calendar.get(Calendar.SECOND); //获取秒    String hourtmp,minutetmp,secordtmp;  //保存输入的时间    int hour,minute,secord;     //保存转换后的时间    //输入时间    hourtmp=JOptionPane.showInputDialog(this,"请输入关机的小时(12小时制)","输入",1);    minutetmp=JOptionPane.showInputDialog(this,"请输入关机的分钟","输入",1);    secordtmp=JOptionPane.showInputDialog(this,"请输入关机的秒钟","输入",1);    //转换时间    hour=Integer.parseInt(hourtmp);    minute=Integer.parseInt(minutetmp);    secord=Integer.parseInt(secordtmp);      long setTime=timeSum(hour, minute, secord); //计算输入时间的总和    long currentlyTime=timeSum(h, m, s);  //计算当前系统时间的总和    long discrepancyTime=setTime-currentlyTime; //获取时间差    if (discrepancyTime<0) {     try {      Runtime.getRuntime().exec("shutdown -s");     } catch (IOException e) {      // TODO Auto-generated catch block      e.printStackTrace();     }    }else {     try {      Runtime.getRuntime().exec("shutdown -s  -t "+discrepancyTime);     } catch (IOException e) {      // TODO Auto-generated catch block      e.printStackTrace();     }     JOptionPane.showMessageDialog(this, "恭喜你,设置成功!", "确认", 2);    }   }   /**    * 计算出时间总和,并返回    * @param h    * @param m    * @param s    * @return    */   public int timeSum(int h,int m,int s) {    int sum=h*3600+m*60+s;    return sum;   }     /**    * 取消关机    */   public void cancel() {    JOptionPane.showMessageDialog(this, "你已经成功取消了关机操作!", "消息", 2);    try {     Runtime.getRuntime().exec("shutdown -a");    } catch (IOException e) {     // TODO Auto-generated catch block     e.printStackTrace();    }   }     public static void main(String[] args) {    java.awt.EventQueue.invokeLater(new Runnable() {       @Override     public void run() {      // TODO Auto-generated method stub      new CloseComputer().setVisible(true);     }    });       }      @Override   public void actionPerformed(ActionEvent e) {    // TODO Auto-generated method stub    if (e.getSource() == countdown) {     countdown();    }    if (e.getSource() == time) {     time();    }    if (e.getSource() == cancel) {     cancel();    }   }  }