Java 實例– 查看線程是否存活

Java實例

以下實例演示瞭如何通過繼承Thread類並使用currentThread()方法來檢測一個線程是否存活：

/*
 author by w3cschool.cc
 TwoThreadAlive.java
 */

public class TwoThreadAlive extends Thread {
   public void run() {
      for (int i = 0; i < 10; i++) {
         printMsg();
      }
   }

   public void printMsg() {
      Thread t = Thread.currentThread();
      String name = t.getName();
      System.out.println("name=" + name);
   }

   public static void main(String[] args) {
      TwoThreadAlive tt = new TwoThreadAlive();
      tt.setName("Thread");
      System.out.println("before start(), tt.isAlive()=" + tt.isAlive());
      tt.start();
      System.out.println("just after start(), tt.isAlive()=" + tt.isAlive());
      for (int i = 0; i < 10; i++) {
         tt.printMsg();
      }
      System.out.println("The end of main(), tt.isAlive()=" + tt.isAlive());
   }
}

以上代碼運行輸出結果為：

before start(), tt.isAlive()=false
just after start(), tt.isAlive()=true
name=main
name=Thread
name=main
name=main
name=main
name=main
name=main
name=main
name=main
name=main
name=main
name=Thread
name=Thread
name=Thread
name=Thread
name=Thread
The end of main(), tt.isAlive()=true
name=Thread
name=Thread
name=Thread
name=Thread

Java實例