CyclicBarrier简单使用

CyclicBarrier就是要实现有福同享有难同当的原理，吃饭的时候，要等室友都到了才会一起去吃食堂，吃饭食堂一起去教室

 每一阶段完成后，才会开始下一阶段

代码部分

package com.java.test.cyclicbarrier;

import lombok.extern.slf4j.Slf4j;

import java.util.Random;
import java.util.concurrent.BrokenBarrierException;
import java.util.concurrent.CyclicBarrier;

/**
 * @Description:
 * @Author: Yourheart
 * @Create: 2023/1/3 17:57
 */
@Slf4j
public class MyThread extends Thread {
    private final CyclicBarrier barrier;
    private final Random random = new Random();

    public MyThread(String name, CyclicBarrier barrier) {
        super(name);
        this.barrier = barrier;
    }

    @Override
    public void run() {
        try {
            log.info(Thread.currentThread().getName() + " - 起床");
            Thread.sleep(random.nextInt(6000));
            log.info(Thread.currentThread().getName() + " - 洗漱完毕");
            //等待其他的室友
            barrier.await();


            log.info(Thread.currentThread().getName() + " - 食堂打完菜开始吃饭");
            Thread.sleep(random.nextInt(6000));
            log.info(Thread.currentThread().getName() + " - 吃饭结束");
            //等待其他还是吃饭的室友
            barrier.await();

            log.info(Thread.currentThread().getName() + " - 准备出发去教室");
            Thread.sleep(random.nextInt(6000));
            log.info(Thread.currentThread().getName() + " - 全部到达教室");
        } catch (InterruptedException e) {
            e.printStackTrace();
        } catch (BrokenBarrierException e) {
            e.printStackTrace();
        }
    }
}

package com.java.test.cyclicbarrier;

import java.util.concurrent.CyclicBarrier;

/**
 * @Description:
 * @Author: Yourheart
 * @Create: 2023/1/3 17:56
 */
public class MainTest {
    public static void main(String[] args) {
        CyclicBarrier cyclicBarrier=new CyclicBarrier(5, new Runnable() {
            @Override
            public void run() {
                System.out.println("该阶段结束...");
            }
        });
        for (int i=0;i<5;i++){
            new MyThread("同学-" + (i + 1), cyclicBarrier).start();
        }
    }
}

　　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>

        <!-- https://mvnrepository.com/artifact/com.oracle.database.jdbc/ojdbc8 -->
        <dependency>
            <groupId>com.oracle.database.jdbc</groupId>
            <artifactId>ojdbc8</artifactId>
            <version>12.2.0.1</version>
        </dependency>
        <!--springboot整合mybatis-->
        <dependency>
            <groupId>org.mybatis.spring.boot</groupId>
            <artifactId>mybatis-spring-boot-starter</artifactId>
            <version>2.1.2</version>
        </dependency>

        <!--添加fastjson依赖-->
        <dependency>
            <groupId>com.alibaba</groupId>
            <artifactId>fastjson</artifactId>
            <version>1.2.70</version>
        </dependency>
        <!-- 热部署模块 -->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-devtools</artifactId>
            <optional>true</optional> <!-- 这个需要为 true 热部署才有效 -->
        </dependency>
        <!--ThreadFactoryBuilder的依赖包,多线程使用-->
        <dependency>
            <groupId>com.google.guava</groupId>
            <artifactId>guava</artifactId>
            <version>30.1-jre</version>
        </dependency>

        <!--Lists.partition要用的依赖-->
        <dependency>
            <groupId>com.google.guava</groupId>
            <artifactId>guava</artifactId>
            <version>21.0</version>
        </dependency>
       <!--ListUtils.partition使用的依赖-->
        <dependency>
            <groupId>org.apache.commons</groupId>
            <artifactId>commons-collections4</artifactId>
            <version>4.4</version>
        </dependency>
        <!--操作redis的依赖-->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-data-redis</artifactId>
        </dependency>
        <dependency>
            <groupId>org.apache.commons</groupId>
            <artifactId>commons-pool2</artifactId>
        </dependency>
        <dependency>
            <groupId>org.apache.commons</groupId>
            <artifactId>commons-lang3</artifactId>
            <version>3.9</version>
        </dependency>


    </dependencies>


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


</project>

 相对于CountDownLatch，CyclicBarrier可以重复使用。