客户端同步服务器时间

客户端同步服务器时间

 

import java.io.BufferedInputStream;   
import java.io.BufferedReader;   
import java.io.IOException;   
import java.io.InputStream;   
import java.io.InputStreamReader;   
import java.net.Socket;   
import java.net.UnknownHostException;   
import java.util.Calendar;   
import java.util.Date;   
import java.util.TimeZone;   
import java.util.logging.Level;   
import java.util.logging.Logger;   
   
/**  
 * SyncTime 获取原子钟的时间，并设置为系统时间  
 * @author Administrator  
 */   
public class SyncTime {   
   
    private static int sleepMinutes = 0;   
    private static final long EPOCH_OFFSET_MILLIS;   
    private static final String[] hostName = {"time-a.nist.gov", "time-nw.nist.gov", "time.nist.gov"};   
   
   
    static {   
        Calendar calendar = Calendar.getInstance(TimeZone.getTimeZone("GMT"));   
        // Java使用的参照标准是1970年，而时间服务器返回的秒是相当1900年的，算一下偏移    
        calendar.set(1900, Calendar.JANUARY, 1, 0, 0, 0);   
        EPOCH_OFFSET_MILLIS = Math.abs(calendar.getTime().getTime());   
    }   
   
    public static void main(String[] args) {   
        GetWebTime();   
    }   
   
    private static Date getNetDate(String hostName) {   
        Date date = null;   
        long result = 0;   
        try {   
            Socket socket = new Socket(hostName, 37);   
            BufferedInputStream bis = new BufferedInputStream(socket.getInputStream(),   
                    socket.getReceiveBufferSize());   
            int b1 = bis.read();   
            int b2 = bis.read();   
            int b3 = bis.read();   
            int b4 = bis.read();   
            if ((b1 | b2 | b3 | b3) < 0) {   
                return null;   
            }   
            result = (((long) b1) << 24) + (b2 << 16) + (b3 << 8) + b4;   
            date = new Date(result * 1000 - EPOCH_OFFSET_MILLIS);   
            socket.close();   
        } catch (UnknownHostException ex) {   
            Logger.getLogger(SyncTime.class.getName()).log(Level.SEVERE, null, ex);   
        } catch (IOException ex) {   
            Logger.getLogger(SyncTime.class.getName()).log(Level.SEVERE, null, ex);   
        }   
        return date;   
    }   
   
    /**  
     * 通过ping命令判断是否离线  
     * @return  
     */   
    public static boolean offLine() {   
        Runtime run = Runtime.getRuntime();   
        try {   
            Process process = run.exec("ping www.hao123.com");   
            InputStream s = process.getInputStream();   
            BufferedReader bis = new BufferedReader(new InputStreamReader(s));   
            String str = bis.readLine();   
            while (str != null) {   
                if (str.startsWith("Reply from")) {   
                    return false;   
                }   
                str = bis.readLine();   
            }   
            process.waitFor();   
        } catch (IOException ex) {   
            Logger.getLogger(SyncTime.class.getName()).log(Level.SEVERE, null, ex);   
        } catch (InterruptedException ex) {   
            Logger.getLogger(SyncTime.class.getName()).log(Level.SEVERE, null, ex);   
        }   
        return true;   
    }   
   
    /**  
     * 通过调用本地命令date和time修改计算机时间  
     * @param date  
     */   
    private static void setComputeDate(Date date) {   
        Calendar c = Calendar.getInstance(TimeZone.getTimeZone("GMT+8"));   
        c.setTime(date);   
        int year = c.get(Calendar.YEAR);   
        int month = c.get(Calendar.MONTH) + 1;   
        int day = c.get(Calendar.DAY_OF_MONTH);   
        int hour = c.get(Calendar.HOUR_OF_DAY);   
        int minute = c.get(Calendar.MINUTE);   
        int second = c.get(Calendar.SECOND);   
   
        c.setTime(new Date());   
        int year_c = c.get(Calendar.YEAR);   
        int month_c = c.get(Calendar.MONTH) + 1;   
        int day_c = c.get(Calendar.DAY_OF_MONTH);   
        int hour_c = c.get(Calendar.HOUR_OF_DAY);   
        int minute_c = c.get(Calendar.MINUTE);   
   
        String ymd = year + "-" + month + "-" + day;   
        String time = hour + ":" + minute + ":" + second;   
        try {   
            // 日期不一致就修改一下日期    
            if (year != year_c || month != month_c || day != day_c) {   
                String cmd = "cmd /c date " + ymd;   
                Process process = Runtime.getRuntime().exec(cmd);   
                process.waitFor();   
            }   
   
            // 时间不一致就修改一下时间    
            if (hour != hour_c || minute != minute_c) {   
                String cmd = "cmd  /c  time " + time;   
                Process process = Runtime.getRuntime().exec(cmd);   
                process.waitFor();   
            }   
        } catch (IOException ex) {   
            Logger.getLogger(SyncTime.class.getName()).log(Level.SEVERE, null, ex);   
        } catch (InterruptedException ex) {   
            Logger.getLogger(SyncTime.class.getName()).log(Level.SEVERE, null, ex);   
        }   
    }   
       
    public static void GetWebTime()   
    {   
        // 检测电脑是否在线    
        while (offLine() && sleepMinutes < 30) {   
            try {   
                Thread.sleep(120000);   
                sleepMinutes += 2;   
            } catch (InterruptedException ex) {   
                Logger.getLogger(SyncTime.class.getName()).log(Level.SEVERE, null, ex);   
            }   
        }   
   
        // 30分钟还没有联线，表示就不上网了，退出吧    
        if (sleepMinutes >= 30)   
        {   
            System.exit(0);   
        }   
   
        // 从网络上获取时间    
        Date date = null;   
        for (int i = 0; i < hostName.length; i++) {   
            date = getNetDate(hostName[i]);   
            if (date != null) {   
                break;   
            }   
        }   
   
        // 修改本机时间    
        if (date != null) {   
            System.out.println("原子钟时间："+date);   
            setComputeDate(date);   
        }   
    }   
}  

 

 

import java.io.IOException;
import java.util.Calendar;
import java.util.Date;
import java.util.TimeZone;

public class ServerHostTime {

 /**
  * lance
  * 
  * @param args
  */
 public static void main(String[] args) {
  // TODO Auto-generated method stub

 }

 /**
  * 通过调用本地命令date和time修改计算机时间
  * 
  * @param date
  */
 @SuppressWarnings("unused")
 private static void setComputeDate(Date date) {
  Calendar c = Calendar.getInstance(TimeZone.getTimeZone("GMT+8"));
  c.setTime(date);
  int year = c.get(Calendar.YEAR);
  int month = c.get(Calendar.MONTH) + 1;
  int day = c.get(Calendar.DAY_OF_MONTH);
  int hour = c.get(Calendar.HOUR_OF_DAY);
  int minute = c.get(Calendar.MINUTE);
  int second = c.get(Calendar.SECOND);

  c.setTime(new Date());
  int year_c = c.get(Calendar.YEAR);
  int month_c = c.get(Calendar.MONTH) + 1;
  int day_c = c.get(Calendar.DAY_OF_MONTH);
  int hour_c = c.get(Calendar.HOUR_OF_DAY);
  int minute_c = c.get(Calendar.MINUTE);

  String ymd = year + "-" + month + "-" + day;
  String time = hour + ":" + minute + ":" + second;
  try {
   // 日期不一致就修改一下日期
   if (year != year_c || month != month_c || day != day_c) {
    String cmd = "cmd /c date " + ymd;
    Process process = Runtime.getRuntime().exec(cmd);
    process.waitFor();
   }

   // 时间不一致就修改一下时间
   if (hour != hour_c || minute != minute_c) {
    String cmd = "cmd  /c  time " + time;
    Process process = Runtime.getRuntime().exec(cmd);
    process.waitFor();
   }
  } catch (IOException ex) {
   ex.getStackTrace();
  } catch (InterruptedException ex) {
   ex.getStackTrace();
  }

 }
}