java 延时的几种方法方法

一时失言乱红尘 2023-06-19 11:18 32阅读 0赞

1、 用Thread就不会iu无法终止

new Thread(new Runnable() { 
                public void run() { 
                    while (true) { 
                        test();
                        try { 
                            Thread.sleep(500);
                        } catch (InterruptedException e) { 
                            // TODO Auto-generated catch block
                            e.printStackTrace();
                        }
                    }
                }
                private void test() { 
                    // TODO Auto-generated method stub
                }
                public Runnable start() { 
                    // TODO Auto-generated method stub
                    return null;
                }
            }.start());

2、 或者用现成的

javax.swing.Timer timer = new javax.swing.Timer(500, new ActionListener() \{ public void actionPerformed(ActionEvent e) \{ repaint(); \} \}；

timer.start();  
3、下面这个方法测试过可以用 java非线程延时

import java.awt.Robot;
    import java.util.Date;
    
    public class test { 
         public   static   void   main(String[]   args)   throws   Exception{    
             Robot  r   =   new   Robot(); 
             System.out.println( "延时前:"+new Date().toString()  ); 
             r.delay(   2000   );   
             System.out.println(   "延时后:"+new Date().toString()   );   
       }   
    }

4、 用这下面的TimeTask类（指定延时）

java里面的sleep()并不能精确定时，TimeTask可以：例下面的小程序：

import java.util.*;
    
    public class test { 
        public static void main(String[] args) { 
            Timer timer = new Timer();// 实例化Timer类
            timer.schedule(new TimerTask() { 
                public void run() { 
                    System.out.println("退出");
                    this.cancel();//如果调用的方法传的参数找不到，将参数放到类里，作为类的属性就找到了。
                }
            }, 5000);// 这里百毫秒
            System.out.println("本程序存在5秒后自动退出");
        }
    }

5.用concurrent包的TimeUnit类延时sleep()方法延时

package concurrency;
    //: concurrency/SleepingTask.java
    // Calling sleep() to pause for a while.
    import java.util.concurrent.*;
    
    public class SleepingTask extends LiftOff { 
      public void run() { 
        try { 
          while(countDown-- > 0) { 
            System.out.print(status());
            // Old-style:
            // Thread.sleep(100);
            // Java SE5/6-style:
            TimeUnit.MILLISECONDS.sleep(100);//MILLISECONDS表示以毫秒为单位延时
          }
        } catch(InterruptedException e) { 
          System.err.println("Interrupted");
        }
      }
      public static void main(String[] args) { 
        ExecutorService exec = Executors.newCachedThreadPool();
        for(int i = 0; i < 5; i++)
          exec.execute(new SleepingTask());
        exec.shutdown();
      }
    } /* Output: #0(9), #1(9), #2(9), #3(9), #4(9), #0(8), #1(8), #2(8), #3(8), #4(8), #0(7), #1(7), #2(7), #3(7), #4(7), #0(6), #1(6), #2(6), #3(6), #4(6), #0(5), #1(5), #2(5), #3(5), #4(5), #0(4), #1(4), #2(4), #3(4), #4(4), #0(3), #1(3), #2(3), #3(3), #4(3), #0(2), #1(2), #2(2), #3(2), #4(2), #0(1), #1(1), #2(1), #3(1), #4(1), #0(Liftoff!), #1(Liftoff!), #2(Liftoff!), #3(Liftoff!), #4(Liftoff!), *///:~