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Java???4??????????

?Java???????????????????????????????????????????????????????????????????????????????????????

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public class ZiYuan {
    private Object object[] = new Object[1];
    private int num = 1;
    private static final Object loc = new Object();
    public void add() {
        synchronized (loc) {
            while (object[0] != null) {
                loc.wait();
            }
            object[0] = "?" + num;
            System.out.println(Thread.currentThread().getName() + "????????" + object[0]);
            num++;
            loc.notifyAll();
        }
    }
    public void delete() {
        synchronized (loc) {
            while (object[0] == null) {
                loc.wait();
            }
            System.out.println(Thread.currentThread().getName() + "??????" + object[0]);
            object[0] = null;
            loc.notifyAll();
        }
    }
}

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public class ShengChan implements Runnable {
    private ZiYuan ziyuan;
    public ShengChan(ZiYuan ziYuan) {
        this.ziyuan = ziYuan;
    }
    @Override
    public void run() {
        while (true) {
            try {
                ziYuan.add();
            } catch (InterruptedException e) {
                e.printStackTrace();
            }
        }
    }
}

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public class XiaoFei implements Runnable {
    private ZiYuan ziyuan;
    public XiaoFei(ZiYuan ziYuan) {
        this.ziyuan = ziYuan;
    }
    @Override
    public void run() {
        while (true) {
            try {
                ziYuan.delete();
            } catch (InterruptedException e) {
                e.printStackTrace();
            }
        }
    }
}

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public class TestMain {
    public static void main(String[] args) {
        ZiYuan yuan = new ZiYuan();
        ShengChan sc = new ShengChan(yuan);
        XiaoFei xf = new XiaoFei(yuan);
        Thread scThread = new Thread(sc);
        scThread.setName("?????");
        Thread xfThread = new Thread(xf);
        xfThread.setName("?????");
        scThread.start();
        xfThread.start();
    }
}

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?????????????Java??Lock???Condition?????????????????/?????

Lock???Condition??

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import java.util.concurrent.locks.Lock;
import java.util.concurrent.locks.ReentrantLock;
import java.util.concurrent.locks.Condition;
public class ZiYuan {
    private Object object[] = new Object[1];
    private int num = 1;
    private static final Lock lock = new ReentrantLock();
    private static final Condition sCondition = lock.newCondition();
    private static final Condition xfCondition = lock.newCondition();
    public void add() {
        try {
            lock.lock();
            try {
                while (object[0] != null) {
                    sCondition.await();
                }
                object[0] = "?" + num;
                System.out.println(Thread.currentThread().getName() + "????????" + object[0]);
                num++;
                xfCondition.signal();
            } catch (InterruptedException e) {
                e.printStackTrace();
            } finally {
                lock.unlock();
            }
        } catch (InterruptedException e) {
            e.printStackTrace();
        }
    }
    public void delete() {
        try {
            lock.lock();
            try {
                while (object[0] == null) {
                    xfCondition.await();
                }
                System.out.println(Thread.currentThread().getName() + "??????" + object[0]);
                object[0] = null;
                sCondition.signal();
            } catch (InterruptedException e) {
                e.printStackTrace();
            } finally {
                lock.unlock();
            }
        } catch (InterruptedException e) {
            e.printStackTrace();
        }
    }
}

?????????

public class ShengChan implements Runnable {
    private ZiYuan ziyuan;
    public ShengChan(ZiYuan ziYuan) {
        this.ziyuan = ziYuan;
    }
    @Override
    public void run() {
        while (true) {
            try {
                ziyuan.add();
            } catch (InterruptedException e) {
                e.printStackTrace();
            }
        }
    }
}

?????????

public class XiaoFei implements Runnable {
    private ZiYuan ziyuan;
    public XiaoFei(ZiYuan ziYuan) {
        this.ziyuan = ziYuan;
    }
    @Override
    public void run() {
        while (true) {
            try {
                ziyuan.delete();
            } catch (InterruptedException e) {
                e.printStackTrace();
            }
        }
    }
}

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public class TestMain {
    public static void main(String[] args) {
        ZiYuan yuan = new ZiYuan();
        ShengChan sc = new ShengChan(yuan);
        XiaoFei xf = new XiaoFei(yuan);
        Thread scThread = new Thread(sc);
        scThread.setName("?????");
        Thread xfThread = new Thread(xf);
        xfThread.setName("?????");
        scThread.start();
        xfThread.start();
    }
}

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????Lock?Condition???????????????????????????????????????????????????????