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Java 实例 - 线程优先级设置

Java 实例 Java 实例

以下实例演示了如何通过setPriority() 方法来设置线程的优先级：

SimplePriorities.java 文件

public class SimplePriorities extends Thread {
   private int countDown = 5;
   private volatile double d = 0;
   public SimplePriorities(int priority) {
      setPriority(priority);
      start();
   }
   public String toString() {
      return super.toString() + ": " + countDown;
   }
   public void run() {
      while(true) {
         for(int i = 1; i < 100000; i++)
         d = d + (Math.PI + Math.E) / (double)i;
         System.out.println(this);
         if(--countDown == 0) return;
      }
   }
   public static void main(String[] args) {
      new SimplePriorities(Thread.MAX_PRIORITY);
      for(int i = 0; i < 5; i++)
      new SimplePriorities(Thread.MIN_PRIORITY);
   }
}

以上代码运行输出结果为：

Thread[Thread-1,1,main]: 5
Thread[Thread-2,1,main]: 5
Thread[Thread-3,1,main]: 5
Thread[Thread-0,10,main]: 5
Thread[Thread-3,1,main]: 4
Thread[Thread-0,10,main]: 4
Thread[Thread-1,1,main]: 4
Thread[Thread-5,1,main]: 5
Thread[Thread-4,1,main]: 5
Thread[Thread-2,1,main]: 4
Thread[Thread-0,10,main]: 3
Thread[Thread-1,1,main]: 3
Thread[Thread-4,1,main]: 4
Thread[Thread-2,1,main]: 3
……

Java 实例 Java 实例