线程中wait()和notify()整合synchronized简单使用

pom文件

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>

    <groupId>com.java</groupId>
    <artifactId>test-study</artifactId>
    <version>1.0-SNAPSHOT</version>

    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.2.1.RELEASE</version>
        <relativePath/>
    </parent>

    <dependencies>
        <!--tomcat容器-->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>
        <!--lombok依赖-->
        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
            <version>1.18.16</version>
        </dependency>
        <!--引入junit单元测试依赖-->
        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
            <version>4.12</version>
        </dependency>
        <!--判断空的用法  -->
        <dependency>
            <groupId>commons-lang</groupId>
            <artifactId>commons-lang</artifactId>
            <version>2.6</version>
        </dependency>

    </dependencies>


    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
            </plugin>
        </plugins>
        <finalName>study</finalName>
    </build>


</project>

  代码部分

package com.java.test.synchorized.wait.notify;

import org.apache.commons.lang.StringUtils;

import java.util.Random;

/**
 * @Description:
 * @Author: Yourheart
 * @Create: 2022/10/21 17:20
 */
public class ConsumerThread extends Thread {

    private final MyQueue myQueue;
    private final Random random = new Random();

    public ConsumerThread(MyQueue myQueue) {
        this.myQueue = myQueue;
    }


    @Override
    public void run() {
        while (true) {
            String result = myQueue.get();
            if (StringUtils.isNotBlank(result)){
                System.out.println("\t\t消费的数据:" + result);
            }
            try {
                Thread.sleep(random.nextInt(1000));
            } catch (InterruptedException e) {
                e.printStackTrace();
            }
        }

    }
}

  

package com.java.test.synchorized.wait.notify;

import java.util.Random;

/**
 * @Description:
 * @Author: Yourheart
 * @Create: 2022/10/21 17:17
 */
public class ProducerThread extends Thread {

    private final MyQueue myQueue;

    private final Random random = new Random();

    private int index = 0;

    public ProducerThread(MyQueue myQueue) {
        this.myQueue = myQueue;
    }


    @Override
    public void run() {
        while (true) {
            String tmp = "生产数据: " + index;
            myQueue.put(tmp);
            System.out.println(tmp);
            index++;
            try {
                Thread.sleep(random.nextInt(1000));
            } catch (InterruptedException e) {
                e.printStackTrace();
            }
        }


    }
}

  

package com.java.test.synchorized.wait.notify;

/**
 * @Description:
 * @Author: Yourheart
 * @Create: 2022/10/21 17:15
 */
public class MyQueue {


    private Object lock=new Object();

    private String[] data = new String[10];
    /**
     * 下一条要获取元素的下标
     */
    private int getIndex = 0;
    /**
     * 下一条要获取元素的下标
     */
    private int putIndex = 0;
    /**
     * data中元素的个数
     */
    private int size = 0;

    /**
     * 向数组中放置元素
     * @param element
     */
    public synchronized void put(String element) {
        if (size == data.length) {
            try {
                wait();
            } catch (InterruptedException e) {
                e.printStackTrace();
            }
        }
        data[putIndex] = element;
        notify();
        ++size;
        ++putIndex;
        if (putIndex == data.length) {
            putIndex = 0;
        }


    }

    /**
     * 从数组中获取元素
     * @return
     */
    public synchronized String get() {
        if (size == 0) {
            try {
                /**
                 * 阻塞线程
                 */
                wait();
            } catch (InterruptedException e) {
                e.printStackTrace();
            }
        }
        String result = data[getIndex];
        ++getIndex;
        if (getIndex == data.length) {
            getIndex = 0;
        }
        --size;
        /**
         * 通知生产者生产数据,因为对象锁是当前的对象,即this对象
         */
        notify();
        return result;
    }

}

  

package com.java.test.synchorized.wait.notify;

import org.junit.Test;

/**
 * @Description:
 * @Author: Yourheart
 * @Create: 2022/10/21 17:15
 */
public class Main {
    @Test
    public void test() throws InterruptedException {
        MyQueue myQueue = new MyQueue();
        ProducerThread producerThread = new ProducerThread(myQueue);
        ConsumerThread consumerThread = new ConsumerThread(myQueue);
        producerThread.start();
        consumerThread.start();
        Thread.sleep(10000);
        /**
         * 进程结束
         */
        System.exit(0);

    }
}

  引入多个线程处理数据

package com.java.test.synchorized.wait.notify;

/**
 * @Description 在MyQueue的基础上做升级
 * @Author qiuxie
 * @Date 2022/10/25 20:25
 */
public class UpgradeMyQueue  extends  MyQueue{

    private Object lock=new Object();

    private String[] data = new String[10];
    /**
     * 下一条要获取元素的下标
     */
    private int getIndex = 0;
    /**
     * 下一条要获取元素的下标
     */
    private int putIndex = 0;
    /**
     * data中元素的个数
     */
    private int size = 0;

    /**
     * 向数组中放置元素
     *
     * @param element
     */
    @Override
    public synchronized void put(String element) {
        if (size==data.length){
            try {
                wait();

            } catch (InterruptedException e) {
                e.printStackTrace();
            }
            /**
             * 利用迭代,进行第二次抢对象锁
             */
            put(element);
        }else {
            putZero(element);
        }
    }

    /**
     * 从数组中获取元素
     *
     * @return
     */
    @Override
    public synchronized String get() {
        if (size == 0) {
            try {
                /**
                 * 阻塞线程
                 */
                wait();
            } catch (InterruptedException e) {
                e.printStackTrace();
            }
            return get();
        }else {
            return getZero();
        }
    }


    private String getZero(){
        String datum = data[getIndex];
        ++getIndex;
        if (getIndex==data.length){
            getIndex=0;
        }
        /**
         * 唤醒生产者生产,因为对象锁是当前对象,this
         */
        notify();
        return datum;
    }


    private void putZero(String element){
        data[putIndex]=element;
        //唤醒等待的消费者线程
        notify();
        ++size;
        ++putIndex;
        if (putIndex==data.length){
            putIndex=0;
        }
    }
}

  

package com.java.test.synchorized.wait.notify;


import org.springframework.util.StopWatch;

/**
 * @Description
 * @Author qiuxie
 * @Date 2022/10/25 20:40
 */
public class UpgradeMain {
    public static void main(String[] args) throws InterruptedException {
        StopWatch stopWatch = new StopWatch();
        stopWatch.start();
        UpgradeMyQueue upgradeMyQueue=new UpgradeMyQueue();
        for (int i = 0; i <5 ; i++) {
            new ConsumerThread(upgradeMyQueue).start();
            new ProducerThread(upgradeMyQueue).start();
        }
        Thread.sleep(10000);

        stopWatch.stop();
        System.out.println(stopWatch.getLastTaskTimeMillis()+"毫秒");
         System.exit(0);
    }
}

  

posted @ 2022-10-25 21:24  不忘初心2021  阅读(22)  评论(0编辑  收藏  举报