多线程

作业1：

        编写多线程程序，模拟多个人通过一个山洞。这个山洞每次只能通过一个人，每个人通过山洞的时间为2秒(sleep)。随机生成10个人，都要通过此山洞，用随机值对应的字符串表示人名，打印输出每次通过山洞的人名。提示：利用线程同步机制，过山洞用一条输出语句表示，该输出语句打印输出当前过山洞的人名，每个人过山洞对应一个线程，哪个线程执行这条输出语句，就表示哪个人过山洞。

package one;public class Test02 {public static void main(String[] args) {        //实例化山洞        Shandong shandong = new Shandong();        //创建10个线程        Thread thread1 = new Thread(shandong, "1");        Thread thread2 = new Thread(shandong, "2");        Thread thread3 = new Thread(shandong, "3");        Thread thread4 = new Thread(shandong, "4");        Thread thread5 = new Thread(shandong, "5");        Thread thread6 = new Thread(shandong, "6");        Thread thread7 = new Thread(shandong, "7");        Thread thread8 = new Thread(shandong, "8");        Thread thread9 = new Thread(shandong, "9");        Thread thread10 = new Thread(shandong, "10");        thread1.start();        thread2.start();        thread3.start();        thread4.start();        thread5.start();        thread6.start();        thread7.start();        thread8.start();        thread9.start();        thread10.start();                         }}//山洞class Shandong extends Thread{    @Override    public void run() {    //上锁        synchronized(this){            System.out.println(Thread.currentThread().getName()+"正在通过,请等待2s");            try {                sleep(2000);            } catch (InterruptedException e) {                // TODO Auto-generated catch block                e.printStackTrace();            }        }    }

作业2：

        用两个线程玩猜数字游戏，第一个线程负责随机给出1~100之间的一个整数，第二个线程负责猜出这个数。要求每当第二个线程给出自己的猜测后，第一个线程都会提示“猜小了”、“猜大了”或“猜对了”。猜数之前，要求第二个线程要等待第一个线程设置好要猜测的数。第一个线程设置好猜测数之后，两个线程还要相互等待，其原则是：第二个线程给出自己的猜测后，等待第一个线程给出的提示；第一个线程给出提示后，等待给第二个线程给出猜测，如此进行，直到第二个线程给出正确的猜测后，两个线程进入死亡状态。

package two;import java.util.Random;public class test2 {    static Object setnumber=new Object();    static Object guess=new Object();    public static void main(String[] args) {        Question question=new Question(setnumber,guess);        Answer answer=new Answer(setnumber,guess);        new Thread(question).start();        new Thread(answer).start();    }}class Question implements Runnable{    Object setnumber;    Object guess;    int number;    public Question(Object setnumber, Object guess) {        // TODO Auto-generated constructor stub        this.setnumber=setnumber;        this.guess=guess;    }    @Override    public void run() {        // TODO Auto-generated method stub        synchronized (setnumber) {            Random rand = new Random();            number=rand.nextInt(100);            State.initialize=1;            System.out.println("我生成了数字："+number);        }//      synchronized()        while(true){            System.out.println("question:"+State.answed);            if(State.answed!=0){                try {                    Thread.sleep(100);                } catch (InterruptedException e) {                    // TODO Auto-generated catch block                    e.printStackTrace();                }            }else {                synchronized (guess) {                    System.out.println("你猜的是："+State.answednumber);                    if(State.answednumber<number){                        State.answed=-1;                        System.out.println("猜小了"+State.answed);                    }if(State.answednumber>number){                        State.answed=1;                        System.out.println("猜大了"+State.answed);                    }if(State.answednumber==number){                        State.answed=2;                        System.out.println("猜对了，就是"+State.answed);                        break;                    }                    Thread.yield();                }            }        }    }}class Answer implements Runnable{    Object setnumber;    Object guess;    int min=0;    int max=100;    Random rand = new Random();    public Answer(Object setnumber, Object guess) {        // TODO Auto-generated constructor stub        this.setnumber=setnumber;        this.guess=guess;    }    @Override    public void run() {        // TODO Auto-generated method stub        while(State.initialize==0){//如果没有运行question方法就等待。            try {                Thread.sleep(100);            } catch (InterruptedException e) {                // TODO Auto-generated catch block                e.printStackTrace();            }        }        synchronized (setnumber) {            while(true){                if(State.answed==0){                    try {                        Thread.sleep(100);                    } catch (InterruptedException e) {                        // TODO Auto-generated catch block                        e.printStackTrace();                    }                }                else {                    synchronized (guess) {                        if(State.answed==1){                            max=State.answednumber;                            State.answednumber=rand.nextInt(max-min)+min;                            System.out.println("我猜："+State.answednumber);                        }                        if(State.answed==-1){                            min=State.answednumber;                            State.answednumber=rand.nextInt(max-min)+min;                            System.out.println("我猜："+State.answednumber);                        }                        if(State.answed==2) {                            System.out.println("我特么终于猜对了～");                            break;                        }                        State.answed=0;                        Thread.yield();                    }                }            }        }    }}class State{//内部static变量充当全局变量的作用来为线程间进行通讯    static int initialize=0;//是否被初始化。    static int answed=0;//用来表示是菜大了还是猜小了    static int answednumber=100;//猜的数字}