併發編程相關類代碼示例-線程篇

1、線程初始化、中斷

public class ThreadDemo1 extends Thread {

    public ThreadDemo1(String name) {
        super(name);
    }

    @Override
    public void run() {
        // interrupted（）是檢測中斷並清除中斷狀態；isInterrupted（）只檢測中斷
        while(!interrupted()) {
            System.out.println(getName() + "線程執行了...");
            try {
                Thread.sleep(2000);
            } catch(InterruptedException e) {
                e.printStackTrace();
                break;
            }
        }
    }

    public static void main(String[] args) {
        ThreadDemo1 d1 = new ThreadDemo1("first-thread");
        ThreadDemo1 d2 = new ThreadDemo1("second-thread");

        // setDaemon(true)設置線程爲守護線程，如果沒有其他用戶線程則結束
//        d1.setDaemon(true);
//        d2.setDaemon(true);

        d1.start();
        d2.start();

        // interrupt()不會真正終止線程
        d1.interrupt();
    }

}

2、實現Runnable接口

public class ThreadDemo2 implements Runnable {

    @Override
    public void run() {
        while (true) {
            System.out.println("thread running...");
        }
    }

    public static void main(String[] args) {
        Thread thread = new Thread(new ThreadDemo2());
        thread.start();
    }
}

3、實現Callable接口

public class ThreadDemo3 implements Callable<Integer> {

    @Override
    public Integer call() throws Exception {
        System.out.println("正在進行緊張的計算...");
        Thread.sleep(2000);
        return 1;
    }

    public static void main(String[] args) throws Exception {
        FutureTask<Integer> task = new FutureTask<>(new ThreadDemo3());
        Thread thread = new Thread(task);
        thread.start();
        Integer result = task.get();
        System.out.println("線程執行結果爲：" + result);
    }
}

4、定時器（常用框架quartz）

public class ThreadDemo4 {

    public static void main(String[] args) {
        Timer timer = new Timer();
        timer.schedule(new TimerTask() {
            @Override
            public void run() {
                System.out.println("timertask is run");
            }
        }, 0, 1000);
    }
}

5、線程池

public class ThreadDemo5 {

    public static void main(String[] args) {
        ExecutorService threadPool = Executors.newFixedThreadPool(10);

        for(int i = 0; i < 11; i++) {
            threadPool.execute(new Runnable() {
                @Override
                public void run() {
                    System.out.println(Thread.currentThread().getName());
                }
            });
        }
    }
}

6、join

public class ThreadDemo6 {

    public void thread1(Thread joinThread) {
        System.out.println("線程1執行了...");
        joinThread.start();
        try {
            joinThread.join();
        } catch (InterruptedException e) {
            e.printStackTrace();
        }
        System.out.println("線程1執行完畢");
    }

    public void thread2() {
        System.out.println("加塞線程開始執行...");
        try {
            Thread.sleep(2000);
        } catch (InterruptedException e) {
            e.printStackTrace();
        }
        System.out.println("加塞線程執行完畢");
    }

    public static void main(String[] args) {
        ThreadDemo6 threadDemo6 = new ThreadDemo6();
        Thread t1 = new Thread(new Runnable() {
            @Override
            public void run() {
                threadDemo6.thread2();
            }
        });
        new Thread(new Runnable() {
            @Override
            public void run() {
                threadDemo6.thread1(t1);
            }
        }).start();
    }
}

7、ThreadLocal

public class ThreadDemo7 {

    private ThreadLocal<Integer> count = new ThreadLocal<Integer>() {
        protected Integer initialValue() {
            return new Integer(0);
        };
    };

    public int getNext() {
        Integer value = count.get();
        value++;
        count.set(value);
        return value;
    }

    public static void main(String[] args) {
        ThreadDemo7 threadDemo7 = new ThreadDemo7();
        new Thread(new Runnable() {
            @Override
            public void run() {
                while(true) {
                    System.out.println(Thread.currentThread().getName() + " " + threadDemo7.getNext());
                    try {
                        Thread.sleep(2000);
                    } catch (InterruptedException e) {
                        e.printStackTrace();
                    }
                }
            }
        }).start();
        new Thread(new Runnable() {
            @Override
            public void run() {
                while(true) {
                    System.out.println(Thread.currentThread().getName() + " " + threadDemo7.getNext());
                    try {
                        Thread.sleep(2000);
                    } catch (InterruptedException e) {
                        e.printStackTrace();
                    }
                }
            }
        }).start();
        new Thread(new Runnable() {
            @Override
            public void run() {
                while(true) {
                    System.out.println(Thread.currentThread().getName() + " " + threadDemo7.getNext());
                    try {
                        Thread.sleep(2000);
                    } catch (InterruptedException e) {
                        e.printStackTrace();
                    }
                }
            }
        }).start();
    }
}