如何用Java实现精确到毫秒的倒计时器

怎么用Java实现精确到毫秒的倒计时器
现在要用Java实现一个倒计时器，我采用的办法是：先获得总的毫秒数matchTime，然后用Timer，每隔一毫秒就让matchTime减1，然后再把matchTime转换成时间的格式。但是这样做出来的时间走的比现实时间要慢得多，如果改成每100秒减100次，就和现实时间差不多了，这也就是说精确到了0.1秒。但是有没有办法精确到毫秒呢？

[解决办法]
看起来是timer的精度不够
[解决办法]
getMilliseconds（），返回毫秒数。
[解决办法]
System.nanoTime()
[解决办法]
windows系统的计时精确度在15毫秒左右。
[解决办法]

Java code

import java.util.Date;import java.io.PrintWriter;import java.io.StringWriter;import java.awt.Font;import java.awt.BorderLayout;import java.awt.event.MouseEvent;import java.awt.event.MouseAdapter;import javax.swing.JFrame;import javax.swing.JLabel;import javax.swing.SwingConstants;/** * TimerFrame - 倒计时窗口 * @author SageZk * @version 1.0 */@SuppressWarnings("serial")public class TimerFrame extends JFrame {    private long time = (long) (1.2 * 60 * 1000L);  //倒计时时间（单位毫秒）    private JLabel lblTime;    private Thread runner;    public TimerFrame() {        super("TimerFrame");        this.lblTime = new JLabel("单击开始");        this.lblTime.setFont(new Font("Monospaced", Font.BOLD, 60));        this.lblTime.setHorizontalAlignment(SwingConstants.CENTER);        this.lblTime.addMouseListener(new MouseAdapter() {            public void mouseClicked(MouseEvent e) {                if (runner != null) runner.start();            }        });        this.runner = new Thread(new Runnable() {            public void run() {                Date t = new Date();                StringWriter sw = new StringWriter();                StringBuffer sb = sw.getBuffer();                PrintWriter pw = new PrintWriter(sw);                long cur = 0L, end = System.currentTimeMillis() + time;                while ((cur = end - System.currentTimeMillis()) &gt; 0) {                    t.setTime(cur);                    pw.format("%1$tM:%1$tS.%tL", t);                    pw.flush();                    lblTime.setText(sb.toString());                    sb.setLength(0);                    try {                        Thread.sleep(6L);                    } catch (InterruptedException e) {                    }                }                lblTime.setText("00:00.000");                try {                    Thread.sleep(1200L);                } catch (InterruptedException e) {                }                lblTime.setText("Bomb!!!");            }        });        this.runner.setDaemon(true);        getContentPane().add(this.lblTime, BorderLayout.CENTER);        setResizable(false);        setBounds(0, 0, 460, 330);        setLocationRelativeTo(null);        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);    }    public static void main(String[] args) {        new TimerFrame().setVisible(true);    }}
[解决办法]
顶楼上的.
[解决办法]
import java.util.Date;
import java.io.PrintWriter;
import java.awt.Font;
import java.swing.JFrame;
  public TimerFrame() {
       super("TimerFrame");
       this.lblTime = new JLabel("单击开始");
       this.lblTime.setFont(new Font("Monospaced", Font.BOLD, 60));
       this.lblTime.setHorizontalAlignment(SwingConstants.CENTER);
       this.lblTime.addMouseListener(new MouseAdapter() {
           public void mouseClicked(MouseEvent e) {
               if (runner != null) runner.start(); 
 
           }
       });
this.runner = new Thread(new Runnable() {
           public void run() {
               Date t = new Date();
               StringWriter sw = new StringWriter();
               StringBuffer sb = sw.getBuffer();
               PrintWriter pw = new PrintWriter(sw);
               long cur = 0L, end = System.currentTimeMillis() + time;
               while ((cur = end - System.currentTimeMillis()) &gt; 0) {
                   t.setTime(cur);
                   pw.format("%1$tM:%1$tS.%tL", t);
                   pw.flush();
                   lblTime.setText(sb.toString());
                   sb.setLength(0);
                   try {
                       Thread.sleep(6L);
                   } catch (InterruptedException e) {
                   }
               }
               lblTime.setText("00:00.000");
               try {
                   Thread.sleep(1200L);
               } catch (InterruptedException e) {
               }
               lblTime.setText("Bomb!!!");
           }
       });
       this.runner.setDaemon(true);
       getContentPane().add(this.lblTime, BorderLayout.CENTER);
       setResizable(false);
       setBounds(0, 0, 460, 330);
       setLocationRelativeTo(null);
       setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
   }

   public static void main(String[] args) {
       new TimerFrame().setVisible(true);
   }

}

[解决办法]
8楼的 Copy 我代码也不贴全，你那能通过编译吗？
[解决办法]
用Timer 不就行了，quartz 也可以。
[解决办法]
看见线程我就头疼  
怎么学那玩意？
[解决办法]
this.runner = new Thread(new Runnable() {  
           public void run() {  
               Date t = new Date();  
               StringWriter sw = new StringWriter();  
               StringBuffer sb = sw.getBuffer();  
               PrintWriter pw = new PrintWriter(sw);  
               long cur = 0L, end = System.currentTimeMillis() + time;  
               while ((cur = end - System.currentTimeMillis()) &gt; 0) {  
                   t.setTime(cur);  
                   pw.format("%1$tM:%1$tS.%tL", t);  
                   pw.flush();  
                   lblTime.setText(sb.toString());  
                   sb.setLength(0);  
                   try {  
                       Thread.sleep(6L);  
                   } catch (InterruptedException e) {  
                   }  
               }  
               lblTime.setText("00:00.000");  
               try {  
                   Thread.sleep(1200L);  
               } catch (InterruptedException e) {  
               }  
               lblTime.setText("Bomb!!!");  
           }  
       });  
       this.runner.setDaemon(true);
[解决办法]
估计毫秒级，应该不好实现。我的机器，所有线程轮一圈，大概10毫秒。
所以，一旦程序中出现sleep，那么下次执行的毫秒数很有可能会滞后（每次最多10毫秒）。

JDK1.5当中的Timer类。楼主可以去看看。如果应用简单的话。应该能够达到要求。

如何用Java实现精确到毫秒的倒计时器

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