interrupt和interrupted和isInterrupted的區別

原創轉載請注明出處：https://www.cnblogs.com/agilestyle/p/11413917.html

 

interrupt

Code Demo

package org.fool.thread;

public class InterruptTest1 {
    public static void main(String[] args) {
        Thread thread = new Thread(new Runnable() {
            @Override
            public void run() {
                for (int i = 0; i < 100000; i++) {
                    System.out.println(Thread.currentThread().getName() + " i = " + i);
                }
            }
        });

        thread.start();

        thread.interrupt();
    }
} 

Note：

從運行結果來看，調用interrupt方法並沒有停止線程

 

interrupted

Code Demo

package org.fool.thread;

public class InterruptTest2 {
    public static void main(String[] args) {
        Thread thread = new Thread(() -> {
            for (int i = 0; i < 10; i++) {
                System.out.println(Thread.currentThread().getName() + " i = " + i);

                if (i == 5) {
                    Thread.currentThread().interrupt();

                    System.out.println("interrupted 1: " + Thread.interrupted());

                    System.out.println("interrupted 2: " + Thread.interrupted());
                }
            }
        });

        thread.start();

    }
}

Console Output

Note：

控制台第一次打印的結果是true，第二次為false；Java Doc中給出的解釋是：測試當前線程是否已經中斷，線程的中斷狀態由該方法清除。即如果連續兩次調用該方法，則第二次調用將返回false（在第一次調用已清除flag后以及第二次調用檢查中斷狀態之前，當前線程再次中斷的情況除外）

所以，interrupted()方法具有清除狀態flag的功能 

 

isInterrupted

Code Demo

package org.fool.thread;

public class InterruptTest3 {
    public static void main(String[] args) {
        Thread thread = new Thread(() -> {
            for (int i = 0; i < 10; i++) {
                System.out.println(Thread.currentThread().getName() + " i = " + i);
            }
        });

        thread.start();

        // main thread interrupt
        Thread.currentThread().interrupt();

        System.out.println(thread.getName() + ":" + thread.isInterrupted());
        System.out.println(thread.getName() + ":" + thread.isInterrupted());
        System.out.println(Thread.currentThread().getName() + ":" + Thread.currentThread().isInterrupted());
        System.out.println(Thread.currentThread().getName() + ":" + Thread.currentThread().isInterrupted());

        // thread interrupt
        thread.interrupt();

        System.out.println(thread.getName() + ":" + thread.isInterrupted());
        System.out.println(thread.getName() + ":" + thread.isInterrupted());
    }
}

Console Output

 

Summary

調用interrupt()方法僅僅是在當前線程中打了一個停止的標記，並不是真正的停止線程

interrupted()測試當前線程是否已經是中斷狀態，執行后具有清除中斷狀態flag的功能

isInterrupted()測試線程Thread對象是否已經是中斷狀態，但不清除中斷狀態flag