Java多线程 原子性操作类的使用

public class AtomicTest {
    

    public static void main(String[] args) {

        final AtomicTicket ticket = new AtomicTicket();
        for (int i = 0; i < 3; i++) {
            new Thread(new Runnable() {
                @Override
                public void run() {
                    while (ticket.getCount() > 0) {
                        System.out.println(Thread.currentThread().getName() + " count: " + ticket.decrement());
                    }
                }
            }).start();
        }
    }
}


class AtomicTicket {

    public AtomicInteger count = new AtomicInteger(100);

    public int decrement() {

        return count.getAndDecrement();
    }

    public int getCount() {
        return count.get();

    }
}

public class AtomicIntegerArrayTest {

    
    private final static AtomicIntegerArray ATOMIC_INTEGER_ARRAY = new AtomicIntegerArray(new int[]{1,2,3,4,5,6,7,8,9,10});

    public static void main(String []args) throws InterruptedException {
        Thread []threads = new Thread[10];
        for(int i = 0 ; i < 10 ; i++) {
            final int index = i;
            threads[i] = new Thread() {
                public void run() {
                    int original =  ATOMIC_INTEGER_ARRAY.get(index);
                    int result = ATOMIC_INTEGER_ARRAY.addAndGet(index, index + 1);
                    System.out.println("currentThread：" + Thread.currentThread().getName() + " , 原始值为：" + original + "，增加后的结果为：" + result);
                }
            };
            threads[i].start();
        }
        for(Thread thread : threads) {
            thread.join();
        }
        System.out.println("=========================>\n执行已经完成，结果列表：");
        for(int i = 0 ; i < ATOMIC_INTEGER_ARRAY.length() ; i++) {
            System.out.println(ATOMIC_INTEGER_ARRAY.get(i));
        }
    }
}

public class AtomicReferenceTest {

    public static void main(String[] args) {
        People people1 =new People("Bom", 0);
        People people2 =new People("Tom",10);

        //先初始化一个值，如果不初始化则默认值为null
        AtomicReference<People> reference = new AtomicReference<>(people1);
        People people3 = reference.get();
        if (people3.equals(people1)) {
            System.out.println("people3:" + people3);
        } else {
            System.out.println("else:" + people3);
        }

        
        boolean b = reference.compareAndSet(null, people2);
        System.out.println("myClass.main-"+b+"--"+reference.get());

        boolean b1 = reference.compareAndSet(people1, people2);
        System.out.println("myClass.main-"+b1+"--"+reference.get());


        new Thread(new Runnable() {
            @Override
            public void run() {
                System.out.println(Thread.currentThread().getName());

                People people = reference.get();
                people.setName("Tom"+Thread.currentThread().getName());
                people.setAge(people.getAge()+1);
                reference.getAndSet(people);
                System.out.println(Thread.currentThread().getName()+reference.get().toString());
            }
        }).start();

        new Thread(new Runnable() {
            @Override
            public void run() {
                System.out.println(Thread.currentThread().getName());

                People people = reference.get();
                people.setName("Tom"+Thread.currentThread().getName());
                people.setAge(people.getAge()+4);
                reference.getAndSet(people);
                System.out.println(Thread.currentThread().getName()+reference.get().toString());
            }
        }).start();

    }

}

 class People {
    private String name;
    private int age;

    public People(String name, int age) {
        this.name = name;
        this.age = age;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public int getAge() {
        return age;
    }

    public void setAge(int age) {
        this.age = age;
    }

    @Override
    public String toString() {
        return "People{" +
                "name='" + name + ''' +
                ", age=" + age +
                '}';
    }
}

public class AtomicIntegerFieldUpdaterTest {

    
    public final static AtomicIntegerFieldUpdater<A> ATOMIC_INTEGER_UPDATER = AtomicIntegerFieldUpdater.newUpdater(A.class, "intValue");

    public static void main(String[] args) {
        final A a = new A();
        for (int i = 0; i < 10; i++) {

            new Thread() {
                public void run() {
                    System.out.println(
                            Thread.currentThread().getName() + " " + ATOMIC_INTEGER_UPDATER.get(a));
                    ATOMIC_INTEGER_UPDATER.addAndGet(a, 11);
                    System.out.println(
                            Thread.currentThread().getName() + " " + ATOMIC_INTEGER_UPDATER.get(a));
                    if (ATOMIC_INTEGER_UPDATER.compareAndSet(a, ATOMIC_INTEGER_UPDATER.get(a), 120)) {
                        System.out.println(Thread.currentThread().getName() + " 对应的值做了修改！");
                    }
                    System.out.println(
                            Thread.currentThread().getName() + " " + ATOMIC_INTEGER_UPDATER.get(a));
                }
            }.start();
        }
    }

    static class A {
        volatile int intValue = 100;
    }
}