Java多線程-線程狀態(tài)

線程狀態(tài)

6個(gè)狀態(tài)定義：java.lang.Thread.State

1. New: 尚未啟動(dòng)的線程的線程狀態(tài)。
2. Runnable: 可運(yùn)行線程的線程狀態(tài)，等待CPU調(diào)度。
3. Blocked: 線程阻塞等待監(jiān)視器鎖定的線程狀態(tài)。處于synchronized同步代碼塊或方法中被阻塞。
4. Waiting: 等待線程的線程狀態(tài)。下列不帶超時(shí)的方式：Object.wait、Thread.join、LockSupport.park
5. Timed Waiting: 具有指定等待時(shí)間的等待線程的線程狀態(tài)。下列超時(shí)的方式：Thread.sleep、Object.wait、Thread.join、LockSupport.parkNanos、LockSupport.parkUntil

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常見線程狀態(tài)切換

新建->運(yùn)行->終止

Thread thread1 = new Thread(new Runnable() {
            @Override
            public void run() {
                System.out.println("thread1當(dāng)前狀態(tài)：" + Thread.currentThread().getState().toString());
                System.out.println("thread1 執(zhí)行了");
            }
        });
System.out.println("沒調(diào)用start方法，thread1當(dāng)前狀態(tài)：" + thread1.getState().toString());
thread1.start();
Thread.sleep(2000L); // 等待thread1執(zhí)行結(jié)束，再看狀態(tài)
System.out.println("等待兩秒，再看thread1當(dāng)前狀態(tài)：" + thread1.getState().toString());

新建->運(yùn)行->等待->運(yùn)行->終止

Thread thread2 = new Thread(new Runnable() {
            @Override
            public void run() {
                try {// 將線程2移動(dòng)到等待狀態(tài)，1500后自動(dòng)喚醒
                    Thread.sleep(1500);
                } catch (InterruptedException e) {
                    e.printStackTrace();
                }
                System.out.println("thread2當(dāng)前狀態(tài)：" + Thread.currentThread().getState().toString());
                System.out.println("thread2 執(zhí)行了");
            }
        });
System.out.println("沒調(diào)用start方法，thread2當(dāng)前狀態(tài)：" + thread2.getState().toString());
thread2.start();
System.out.println("調(diào)用start方法，thread2當(dāng)前狀態(tài)：" + thread2.getState().toString());
Thread.sleep(200L); // 等待200毫秒，再看狀態(tài)
System.out.println("等待200毫秒，再看thread2當(dāng)前狀態(tài)：" + thread2.getState().toString());
Thread.sleep(3000L); // 再等待3秒，讓thread2執(zhí)行完畢，再看狀態(tài)
System.out.println("等待3秒，再看thread2當(dāng)前狀態(tài)：" + thread2.getState().toString());

新建->運(yùn)行->阻塞->運(yùn)行->終止

Thread thread3 = new Thread(new Runnable() {
            @Override
            public void run() {
                synchronized (Demo2.class) {
                    System.out.println("thread3當(dāng)前狀態(tài)：" + Thread.currentThread().getState().toString());
                    System.out.println("thread3 執(zhí)行了");
                }
            }
        });
synchronized (Demo2.class) {
    System.out.println("沒調(diào)用start方法，thread3當(dāng)前狀態(tài)：" + thread3.getState().toString());
    thread3.start();
    System.out.println("調(diào)用start方法，thread3當(dāng)前狀態(tài)：" + thread3.getState().toString());
    Thread.sleep(200L); // 等待200毫秒，再看狀態(tài)
    System.out.println("等待200毫秒，再看thread3當(dāng)前狀態(tài)：" + thread3.getState().toString());
}
Thread.sleep(3000L); // 再等待3秒，讓thread3執(zhí)行完畢，再看狀態(tài)
System.out.println("等待3秒，讓thread3搶到鎖，再看thread3當(dāng)前狀態(tài)：" + thread3.getState().toString());