多线程案例

1.三个售票窗口同时出售20张票

    public class Demo1
    {
     
        public static void main(String[] args)
        {
            TicketOffice ticketOffice = new TicketOffice(new Object(), 20);
            new Thread(ticketOffice, "窗口1").start();
            new Thread(ticketOffice, "窗口2").start();
            new Thread(ticketOffice, "窗口3").start();
        }
    }
     
    class TicketOffice implements Runnable
    {
        private Object object;
     
        private int ticketNum;
     
        public TicketOffice(java.lang.Object object, int ticketNum)
        {
            this.object = object;
            this.ticketNum = ticketNum;
        }
     
        @Override
        public void run()
        {
            while (ticketNum > 0)
            {
                synchronized (object)
                {
                    if (ticketNum <= 0)
                    {
                        System.out.println(Thread.currentThread().getName() + "没有票了");
                    }
                    else
                    {
                        System.out.println(Thread.currentThread().getName() + "卖出了一张票，剩余" + --ticketNum + "张票");
                        try
                        {
                            Thread.sleep(1000L);
                        }
                        catch (InterruptedException e)
                        {
                            e.printStackTrace();
                        }
                    }
                }
            }
        }
    }

2.创建两个线程，其中一个输出1-52，另外一个输出A-Z。输出格式要求：12A 34B 56C 78D ...

    public class Demo2
    {
        public static void main(String[] args)
        {
            Object object = new Object();
            new Thread(new Number(object)).start();
            new Thread(new Character(object)).start();
        }
    }
     
    class Number implements Runnable
    {
        private Object object;
     
        public Number(Object object)
        {
            this.object = object;
        }
     
        @Override
        public void run()
        {
            synchronized (object)
            {
                for (int i = 1; i < 53; i++)
                {
                    if (i > 1 && i % 2 == 1)
                    {
                        System.out.print(" ");
                    }
                    System.out.print(i);
                    if (i % 2 == 0)
                    {
                        object.notifyAll();
                        try
                        {
                            object.wait();
                        }
                        catch (InterruptedException e)
                        {
                            e.printStackTrace();
                        }
                    }
                }
            }
        }
    }
     
    class Character implements Runnable
    {
        private Object object;
     
        public Character(Object object)
        {
            this.object = object;
        }
     
        @Override
        public void run()
        {
            synchronized (object)
            {
                for (char i = 'A'; i <= 'Z'; i++)
                {
                    System.out.print(i);
                    object.notifyAll();
                    if (i < 'Z')
                    {
                        try
                        {
                            object.wait();
                        }
                        catch (InterruptedException e)
                        {
                            e.printStackTrace();
                        }
                    }
                }
            }
        }
    }

3.

启动3个线程打印递增的数字, 线程1先打印1,2,3,4,5, 然后是线程2打印6,7,8,9,10, 然后是线程3打印11,12,13,14,15. 接着再由线程1打印16,17,18,19,20….以此类推, 直到打印到75. 程序的输出结果应该为:

线程1: 1
线程1: 2
线程1: 3
线程1: 4
线程1: 5

线程2: 6
线程2: 7
线程2: 8
线程2: 9
线程2: 10
…

线程3: 71
线程3: 72
线程3: 73
线程3: 74
线程3: 75

    public class Demo3
    {
     
        public static void main(String[] args)
        {
            Object object = new Object();
            new Thread(new PrintRunnable(object,1)).start();
            new Thread(new PrintRunnable(object,2)).start();
            new Thread(new PrintRunnable(object,3)).start();
        }
     
    }
     
    class PrintRunnable implements Runnable
    {
        private static volatile int printNum = 0;
     
        private Object object;
     
        private int threadId;
        
        public PrintRunnable(Object object, int threadId)
        {
            super();
            this.object = object;
            this.threadId = threadId;
        }
     
        @Override
        public void run()
        {
            while (printNum < 75)
            {
                synchronized (object)
                {
                    if (printNum / 5 % 3 + 1 == threadId)
                    {
                        for (int i = 0; i < 5; i++)
                        {
                            System.out.println("线程" + threadId + ":" + (++printNum));
                        }
                        object.notifyAll();
                    }
                    else
                    {
                        try
                        {
                            object.wait();
                        }
                        catch (InterruptedException e)
                        {
                            e.printStackTrace();
                        }
                    }
                }
            }
        }
    }