爲什麼在我調用Thread.currentThread（）之後thread.isInterrupted（）返回false中斷（）

Question

當我運行這個測試時，爲什麼sleepThread.isInterrupted()總是返回false？

（我不得不執行Thread.currentThread().interrupt()設置中斷標誌時，趕上InterruptedException）。

@Test 
public void t() { 
    Thread sleepThread = new Thread() { 
     @Override 
     public void run() { 
      try { 
       Thread.sleep(5 * 1000); 
      } catch (InterruptedException e) { 
       System.out.println("have been interruptted...."); 
       e.printStackTrace(); 

       Thread.currentThread().interrupt(); 

       // in here this.isInterrupted() will return true 
       System.out.println("now , instant interrupt flag : " 
       + this.isInterrupted()); 
      } 
     } 
    }; 
    sleepThread.start(); 

    try { 
     sleepThread.interrupt(); 
     Thread.sleep(2 * 1000); 

     // in here ,why sleepThread.isInterrupted() return false ? 
     System.out.println("sleep thread interrupt flag : " 
     + sleepThread.isInterrupted()); 
    } catch (InterruptedException e) { 
     e.printStackTrace(); 
    } 
} 

這是輸出：因爲達到

System.out.println("sleep thread interrupt flag : " + sleepThread.isInterrupted()); 

線程的最後一條語句會死的時候

have been interruptted 
now , instant interrupt flag : true 
java.lang.InterruptedException: sleep interrupted 
    at java.lang.Thread.sleep(Native Method) 
    at com.roundwith.concurrent.Interrupt_Test$1.run(Interrupt_Test.java:15) 
sleep thread interrupt flag : false 

Answer 1

它。

嘗試去除主線程中2秒鐘的睡眠並且您會看到不同（嘗試幾次運行 - 它可能仍會打印錯誤，但至少主線程有機會看到其他線程還活着）。

Answer 2

嘗試改變，

Thread.sleep(2 * 1000); 

到

//Thread.sleep(2 * 1000);