JUC-8-lock和Condition使用

aaarticlea/png;base64,iVBORw0KGgoAAAANSUhEUgAAANwAAADHCAYAAABySz3ZAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsMAAA7DAcdvqGQAABRESURBVHhe7Z1NzxxHEcfzefARJBAJyHY4kCA5sfNq4zw+JBIQyGM4EIWDBcKSE+QDBB5HMhYChCyZS2QJKXyC8LWGqe6t6eqa6u6ZnZne2Z3/4Sfv9HtX13+md5/p8gs3btxoAAB1eOGTTz4xMwAA80Jac4J77UdXAAALA8EBUBEIDoCKQHAAVASCA6AiEBwAFYHgAKgIBFeJO/efN//+7/+axxd3zfx9WapdsAwQ3Excu/vEOf7Du5f7ea/ebO49/drlP/vqSXP+ar/MPizVLliOoxTctbO7zb2L583jr7yz+Tv8g+b87HAOlxMcMfRJROUejxAPnnDHRVFwr79+pXnrF1eam7+90tz67KqDPlMa5Vl1loQcWwpN8uyATlcS3FDOL77G0+qEyQrujTutyD692vz4oQ3lURmr7hJce/Vu83AnNrqj3xFPtDt3HzQP70NwYN0kBUdCskRmUUt0vH0a+iSj7zjneuv5tHVmtfWkdp999by5d9aWvx+eoM/asveMbaprl8rtvj9JpODkDYKxxs5izfH4/s1QfmC7zFJ2AOMxBUdbxdyTTUNlre3lWz+72tz+Y8ufrjZvf3S1lz8G/oHAO0R58eUPChrdRvc9yCivnzbeee12ibUJbik7gP0wBUffz7SovnX5GxE6n+rINggS2o23rzTX32w//2Wq4LyTPXv6oLkzYOG7p2Fbnu/kfKd36cJBuSzhtqpt+1JYkYh24pDtujYKW8pu/JknETF2S1lqdyk7gP0wBUc/imhBES+ffdNh5VEd2QZx+9HL3ef3HtUTHN/VLce18jqnVE7L4uKnS7bdFQpuKTuA/TEFl9pO5gRHdWQbxHtfeMGR2Cx0+RzjBJd3bu/UYTvFjqbFkhScMYZ1Cm4ZO4D9WVRwjCU2wiqbItyRy9/hlhPcrl0IDuyJKbi5tpSMJTbCKpuDHGTIwneONnIrVRZceovGY5tHcOWbCjNIcDPbAeyPKbi5fjRhLLERVtkc184edD9V85d6ztN/h2MBkCNyOXKy3I8FQxxNi9699dI6LqVZbTBDBcdjedzOpbR1JkrtLmUHsB+m4Ob6swBjiY2wypZgp7CQzsOOaJajv0FJsY5wNCl6yeML/3cr2QbXT2E5cKpONIYR7S5lB7AfpuCINf7hm3FPs6dBeLQFs96l5Hcu43L9J8dYR7vW9s9/q3rWjuPh3ZudEKcKjqA/Mei/he0rOFd+ITuA8SQFR5CQck86yqstNgCOmazgCNoq0vcz+lFkDS8vA3DMFAUHAJgPCA6AikBwAFQEggOgIhAcABWB4ACoCAQHQEUgOAAqAsEBUJFOcLdu3QIALAyecABUBIIDoCIQHAAVgeAAqAgEB0BFIDgAKjJYcO9c+0Hz+/duN//88Lz58u7HDvpMaZRn1QEAxAwW3JfnHzf/+dVvTCjPqnMM+Fgkw8PSgW1T8heK/5ILVlwU3PsfnLl/LaFJZNljYojgKLgORQSjkHMIpLNtFhXcm9d/2Hz6+SP32RKZhMpQWaoj2yDm/F90loSDo0aRt8jAOwP6fDwNQZpJgjv/5Xnz8NFf3WdLZBIqQ2WpjmyDmPN/0VkSS3D0VNOh71JBVwGYJLjfffqHSHCvfful5u3vX27e+O5Lza+vXW/e+d5ld/3ns/ddGSpLdWQbxBz/i45/lIdYjSwCuc3joKecJyefqu/TnzQfvRIHTKV6Z6+823uiyScep4Hjgm+s8uuB+9rAvqKC58pw8Owv3bURaHdvwX32+Rc9wf3tgw+bf/zkI/f5Xz89b/7+wc+bd1vRURkqS3VkG8TU/0XHGegiTMIJaTdp/n7F6Y9bgbAhWYy5+tKA+gnnjRmMm0oDx0d0MxbrzgKSYkz7iy/L/kKQz80muDdefClsIVvB8efr33nRlUkJjrHERlhlLTgysLzrSANQvPx7Z60R3ITJiPHTqVS/JzjKU8bzZfA97tjxYvHrGPmAEGIoKwRZKmukSbKC01vKlOBeE4KztpSMJTbCKivxkxRbx55IDKG5cOR+4tn6vbbwhNsKvAOiG3HnG0nBDRTnFMHpH01IWCXBWT+aMJbYCKusRE/CbSOF0zuDtQbhrSVfp4wo65cFFz/NZHlOA8eJW8unT9z/U8FrzNtE9h2XJvwn9hdfNviL95+9BTfXnwUYS2yEVVbCE+HtoP+faoLTeyOoraAQSq6+FhCJ0W05d0bDr5SnSycQtZ4sJPYXeXPX/kL+EMq1Pnd/whOOOPU/fJdwBua7m1ug+IkHwBiKgmNO9dWuIbgtaHsXlH+CAGAfBgsOLy8DMJ3BggMATAeCA6AiEBwAFYHgAKgIBAdARSA4ACoCwQFQEQgOgIpAcABUZLDg8KYJANMZLDiEyRvPkm3XRM6D37CXJyiisid+XrC0pvoomKYouC2HybPOw7l0qpMxKgPB9fMlx/hS+KKC23qYvKmCG0rJiWuTG89cgpM29G0e/42JmCS4rYfJg+D645lLcKd6sHeS4BAmryy4TpT3w8nfbjy7tsn5UuV4zJzWjVelhzmyw/t8P04K56fSboe++2OJ2+A+yCbWeGRbubp+fJRO9vRjkltFXo9Dhx/kOcixue3trv+eDRJ29G3FZV35zDyygkOYPDLmEMGFY/q+PV8nbjtTrtCvzOfPkRNYaaJvfW2WlzbR4xlVl8a++0zpwvn4qSbLULprw0hbEjk2OV9ep96NgudkrCnbiaA5zia4zYXJcwaN23DpVCcSnBaHv+4vTqKc7rddYB6npLt5iLKhLZUm+tbXpTZ64xlVl+bZn3OULuwXtxHsszTR2OT81E3ClxXzK5U10iRZwSFMXnzNSKNmhRS1nSmn+80smjUmM030ra9LbfTGM6puEBbl0U2O7B7tRFSZVNrS8A6Ix0hpacEZazq34LYeJk+XdW05xxDizQkpajtTTvXLfchxnF+kx2imub5Df9Gcd+XZXqn8bjyGjdJ1Y+G4umYounDdlRP1apAem7Gl3PlPbIt4nTrb7Cs4hMnzaXQn5LquvlwM5Ty+L3/dXxy7HF3rfnlO3Kde1EhcRhrBbboxyzlz+TaN8+VNRdal8Zg/miTq+nnGbVnfa/j7HF87pxYirgHPRffLQjLnp/yFxh3KteuJMHlAkxLoUvDWTaY5x+WbixtPuPmcMkXBMVsOk3dq1BScfiJI3Fa0fbpYgjxVBgsOLy+fDrUEx1vxWk/SY2Cw4AAA04HgAKgIBAdARSA4ACoCwQFQEQgOgIpAcABUBIIDoCIQHAAVGSw4vGkCwHQGCw5h8taL9YY+SHNIexUFt+0webvjG0a+PmN3CPjl31oOdCovGa9WcAiTt7u+6Ivr0IKLj7fUcSBvj+M/RrNawSFMHl/7f1OngDmtJvIAZ00HOsRB0blZreAQJo/Dz4X6VtuhHaN9N6b2qWCE0Qv5ol/lCPLUdghjED9ptAPl2hwzHusEs5vnAW80c1DTXpqs4BAmL752fXFZKeZc+7sF6cbo+vNi4bxoARNj43xXxtUL6fK62OaA8ej5R4JTfR8jNe2lGSW47YXJs6/J+FJw2fbdooRx+DZ2C2a0IfvsFlvUd2VozAkRDGtzxHhUmizPZY6NmvbSZAWHMHnxtRyL/CEl2/7YBRP5cVoQnnQYnz/EgWTdEeNRabrvY6SmvTRZwW09TJ6+ZvhJxm1m288tmMsztjPcbju2e8ZY+m0KByq1OWA8ev5ybtJe3P6xUdNemqzgth4mT/5oQnmMNmy2/cyC+Wu/aFxX3kgIjgvi8nY3FE4PC01tCHtk2iyOZ2dLX69N1z+akDOKcRwjNe2lyQqOQJi8deIWOrOwcxHf7WNnA32kvaz8ouAYhMlbH27rOuPTxguqf+fn7Zb8Ewwo28tisODw8vI2kFskAgLLM9ZegwUHAJgOBAdARSA4ACoCwQFQEQgOgIpAcABUBIIDoCIQHAAVgeAAqMhgweFNEwCmM1hwCJPH78qFd+fWxpi51GLKmPy7iv3TGnNxiPUsCm7LYfIYfkl4DYKTx3UkbnwLCM7Pud+m62vAaYXcmEovQ29OcFsPk+fShGOt6QlXayxTBSfR9vXX6RvE5gS39TB5RO6g5yE5BcG5tMyB1s0JDmHy6MR3cDa9QNxfV6eX19adKbyaRo/Fpe3mQmld/xTbZdcPzZlsUhqPzOvayQiuK2PMNWffbl0S8w6Ci+tKAepx6xPzuXyfp6/7NnB5bh79MeTmbpEVHMLkWQvCZf3iRIsi293ld2Nz/XjH5bzQj+93fsGJMBA7ocXjkWWDqKQddF7UVyS4xFyjfmL7urLGPELezi4i37JxaQ3y+fJzygbt5z3CIHKfklGC21yYPMoTIogWiIyuBBIvkrWA/tqsa6TlkGPp0qK56P7T19Q320Xib1Zxvaiv3Xj7bYu5Zuyry3JanGeV39m4tAaD1iisZ8oGXNf0n8zcuZ4kKziEyQsLoq/Ti+mNnXVCq66RlkOPzaVFc9H9p69zfWubdOmiTnauGfv6sv15hDyrfEgrrkEpX/SdtUHOfzJzl20wWcEhTJ42plgg99nYruz6yS0E1w39+H5TC24hx9Kl7Ss4NR7i/CK0re3N5Tv79toWcy0JTuRzWpfHdtmtKxGtnRqHq9Nbg1J+3JZlg6z/ZObO7Uiygtt6mDwycO5XSl4kbrfvlOmF4DH7em26+NEk54SMHotLE/X6/ReuxXgI6XgE2YHziMiJM3Mt2dc5sxCUhNeNgu5yv9LGvgz1ba9BKd/nieuEDbL+k5k7XWuygiO2HibPLYK4uy1FdOfNOOEpUXLOU6QoOGbLYfLcFmJGAXhH03fasPWh/vQT5hSRf9LZCoMFh5eX50VvX7bmeFtlsOAAANOB4ACoCAQHQEUgOAAqAsEBUBEIDoCKQHAAVASCA6AiEBwAFRksOLxpAsB0BgsOYfKmI/vSb6qDPt1pgYXeKz3EGhQFt+UwefroRZe+5wmCkuD4JWl9HITQx07mYs0vEG9OcFsPkzdVcDmH0Yst27Tq0ZEdEt4Q5xvjqL6sfcM5NGPmsQ+rE9zWw+TVFFx80NWu55+QZQcZ66hrPX+3OcEhTF5ZcJ0oVZg0HkvU3u0gGLnY3rFCP0nBqXRrTla/YZwhXW4j5Xw4bQ2E+cZjl3bpzVcJKJcv18Aq27ORMQZfp7/+XE+TFRzC5O2MWRRcIkScKRDuKyy2/OzKqXqMTM/OqTAPOz/0vxZ4nJFIonl620fCGJ0vP9s2ytva92GtP/cpGSW4zYXJU4vAuDqR4PRC+eteeynBifZCG6EeI9vmNHNOut/WQbiMhB3RancNWHaQac7x1ZN5VL5cg4KNCNvW6fXnepKs4BAmL75m5ELOIjjxObRR6Dc3J92v4XgS3f9asOwg09KC2tm/lC/XIGOjvK3T6y/bYLKC23qYPF3WteUMLIyfMbhur79Q8rNuQzkazUGWyc1J97sbs2xPhsGT4+L8NcDzkD/oxPOM18LVEXYZlh+3Zdkob2uqZ68/tyPJCg5h8nwafRfkuq6+XMCCwWV7qR9NuI8gkHi8XJ/HY5XRNtHzYBtxeelYzqGEU68FniPC5BnIsmA8brGVqGpQchAwL0XBMVsOk1cLt1Wp/KSRf1YByzNYcHh5GYDpDBYcAGA6EBwAFYHgAKgIBAdARSA4ACoCwQFQEQgOgIpAcABUBIIDoCKDBYc3TQCYzmDBrfFdSn0qYAn0G+Vg25R8Th/l0RQFt+bTAocSHL9kjBd/t8eigttamDwL88wUnzHD0RagmCS4rYXJs9CCkwdFXf5KD2+CwzBJcGsKk8cnmInueLt7vIunjxOHP5nrwhHcD5P3eT6tO7krT267tqzTvkFw1hNNPvE4DawbPsEt1999TYh8JXFKPONzXfl9BbeaMHlqklY6T1wfi9dG5KeRr+vF48pmw6D1P3djMNLA+pFPIvYV8h32k+hmLP0h43ME7YBmE9yhwuTxxGQQHZcuJ288ymOjUhuhvvW0Mp+iQlCuP92H0Q5YP9Ifin4kBTnC5zhNkhXcWsLkMTxxFt5cgvPthLta1K4UnPjc9WGkgeOAf2WmG2239knBjfc5TpNkBbeaMHntJO+prWLvbuMcv7SlTAhOGcnt5w2R6TZcO2IMnAaOA7d2T580D8UOhf2ot6VkPxrhc1xfkhXcWsLkEXQ36rZ70few4Oz+uvCjiSW4naG4/X4YtNAHfqU8HTqBqPVjIXX+1vMxcd2ufygX+5xsk8kKjjjmMHmlx/s++LsiiziI1ioLgKYoOGbtYfK884s7j7E1mAu35WzvivwdwCoDgMVgwR3Dy8tyS0lADGBtDBYcAGA6EBwAFYHgAKgIBAdARSA4ACoCwQFQEQgOgIpAcABUBIIDoCKDBYcweQBMZ7DgECav3IcsO6YeOB5KPld6Yb4oOITJ6wsnf6wjLTi89Hz8LCo4hMlLCI6M/vR5a3gtxLTgfB0c6zl1JgkOYfJswfGR/N5h1IzgcHB1G0wSHMLkxSLy1+HppI2bEpz1RJNPPE4DdeCvBHL93XY/8pWBJ75VWVd+X8EhTB7XEwYWIvN5QUiybOozldNlOQ3UI15H7yvkO35djJgmvJYZnyNoJzOb4LYeJo/K6B885LUsG32mceqxGf2Dekh/KPqRFOQIn+M0SVZwCJPH9eTnePuQEmfqczc2Iw3UhW+W/J2c0tKCG+9znCbJCg5h8rieMLASiew3Ktv7HPp29cTYOQ3Uxa0BwuTZ0N2oe6JE38OC0/prX26JMHluf278ssjpsqz8zGV4YQi3iPiV8qB0AlHrwELq/K3nY+K6XcdQLvY52SaTFRyBMHnz4O+mLP4gdqssOF2KgmMQJm86bqva3k35u4NVBpw2gwWHMHkATGew4AAA04HgAKhIJ7gbN24AABbGCc7KAAAswwuXLl1qAAA1uNT8H+LjmdeWz8fGAAAAAElFTkSuQmCC" alt="" />

在 Condition 对象中，与 wait、notify 和 notifyAll 方法对应的分别是

                                       await、signal 和 signalAll。

Condition 实例实质上被绑定到一个锁上。

要为特定 Lock 实例获得 Condition 实例，请使用其 newCondition() 方法。

package com.wf.zhang.juc;

import java.util.concurrent.locks.Condition;
import java.util.concurrent.locks.Lock;
import java.util.concurrent.locks.ReentrantLock;

/*
 * 生产者消费者案例：
 */
public class TestProductorAndConsumerForLock {

    public static void main(String[] args) {
        Clerk clerk = new Clerk();

        Productor pro = new Productor(clerk);
        Consumer con = new Consumer(clerk);

        new Thread(pro, "生产者 A").start();
        new Thread(con, "消费者 B").start();

//         new Thread(pro, "生产者 C").start();
//         new Thread(con, "消费者 D").start();
    }

}

class Clerk {
    private int product = 0;

    private Lock lock = new ReentrantLock();
    private Condition condition = lock.newCondition();

    // 进货
    public void get() {
        lock.lock();

        try {
            if (product >= 1) { // 为了避免虚假唤醒，应该总是使用在循环中。
                System.out.println("产品已满！");

                try {
                    condition.await();
                } catch (InterruptedException e) {
                }

            }
            System.out.println(Thread.currentThread().getName() + " : "
                    + ++product);

            condition.signalAll();
        } finally {
            lock.unlock();
        }

    }

    // 卖货
    public void sale() {
        lock.lock();

        try {
            if (product <= 0) {
                System.out.println("缺货！");

                try {
                    condition.await();
                } catch (InterruptedException e) {
                }
            }

            System.out.println(Thread.currentThread().getName() + " : "
                    + --product);

            condition.signalAll();

        } finally {
            lock.unlock();
        }
    }
}

// 生产者
class Productor implements Runnable {

    private Clerk clerk;

    public Productor(Clerk clerk) {
        this.clerk = clerk;
    }

    @Override
    public void run() {
        for (int i = 0; i < 20; i++) {
            try {
                Thread.sleep(200);
            } catch (InterruptedException e) {
                e.printStackTrace();
            }

            clerk.get();
        }
    }
}

// 消费者
class Consumer implements Runnable {

    private Clerk clerk;

    public Consumer(Clerk clerk) {
        this.clerk = clerk;
    }

    @Override
    public void run() {
        for (int i = 0; i < 20; i++) {
            clerk.sale();
        }
    }

}