Spring Boot集成ShedLock分布式定时任务的实现示例

2024-04-02 19:04:59 657人浏览薄情痞子

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摘要

目录一、ShedLock是什么？二、落地实现1.1 引入依赖包1.2 配置数据库连接信息1.3 创建Mysql数据表1.4 配置LockProvider1.5 创建定时Job1.6

一、ShedLock是什么？

官方地址：GitHub.com/lukas-kreca…

以下是ShedLock锁提供者，通过外部存储实现锁，由下图可知外部存储集成的库还是很丰富的

本篇教程我们基于JdbcTemplate存储为例来使用ShedLock锁。

二、落地实现

1.1 引入依赖包

shedlock所需依赖包：


<dependency>
    <groupId>net.javacrumbs.shedlock</groupId>
    <artifactId>shedlock-spring</artifactId>
    <version>4.23.0</version>
</dependency>
 <!--每个外部存储实例所需依赖包不一样，这里是jdbc-->
<dependency>
    <groupId>net.javacrumbs.shedlock</groupId>
    <artifactId>shedlock-provider-jdbc-template</artifactId>
    <version>4.23.0</version>
</dependency>

JdbcTemplate依赖包：


<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-jdbc</artifactId>
</dependency>
<dependency>
    <groupId>mysql</groupId>
    <artifactId>mysql-connector-java</artifactId>
    <scope>runtime</scope>
</dependency>

WEB工程依赖包：


<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-web</artifactId>
</dependency>

1.2 配置数据库连接信息


server:
  port: 9999
spring:
  datasource:
    url: jdbc:mysql://192.168.31.158:3306/testjdbc?useUnicode=true&characterEncoding=UTF-8&serverTimezone=Asia/Shanghai
    username: root
    passWord: 123456
    driver-class-name: com.mysql.cj.jdbc.Driver
    type: com.mysql.cj.jdbc.MysqlDataSource

1.3 创建Mysql数据表


# MySQL, MariaDB
CREATE TABLE shedlock(name VARCHAR(64) NOT NULL, lock_until TIMESTAMP(3) NOT NULL,
    locked_at TIMESTAMP(3) NOT NULL DEFAULT CURRENT_TIMESTAMP(3), locked_by VARCHAR(255) NOT NULL, PRIMARY KEY (name));

# Postgres
CREATE TABLE shedlock(name VARCHAR(64) NOT NULL, lock_until TIMESTAMP NOT NULL,
    locked_at TIMESTAMP NOT NULL, locked_by VARCHAR(255) NOT NULL, PRIMARY KEY (name));

# oracle
CREATE TABLE shedlock(name VARCHAR(64) NOT NULL, lock_until TIMESTAMP(3) NOT NULL,
    locked_at TIMESTAMP(3) NOT NULL, locked_by VARCHAR(255) NOT NULL, PRIMARY KEY (name));

# MS SQL
CREATE TABLE shedlock(name VARCHAR(64) NOT NULL, lock_until datetime2 NOT NULL,
    locked_at datetime2 NOT NULL, locked_by VARCHAR(255) NOT NULL, PRIMARY KEY (name));

# DB2
CREATE TABLE shedlock(name VARCHAR(64) NOT NULL PRIMARY KEY, lock_until TIMESTAMP NOT NULL,
    locked_at TIMESTAMP NOT NULL, locked_by VARCHAR(255) NOT NULL);

1.4 配置LockProvider



// 标识该类为配置类
@Configuration
// //开启定时器
@EnableScheduling
// 开启定时任务锁，指定一个默认的锁的时间30秒
@EnableSchedulerLock(defaultLockAtMostFor = "PT30S")
public class ShedlockJdbcConfig {

    
    @Bean
    public LockProvider lockProvider(DataSource dataSource) {
        return new JdbcTemplateLockProvider(
                JdbcTemplateLockProvider.Configuration.builder()
                        .withJdbcTemplate(new JdbcTemplate(dataSource))
                        .usingDbTime()
                        .build()
        );
    }
}

1.5 创建定时Job



@Component
@CommonsLog
public class TimeTaskJob {

    private static Integer count = 1;

    // @SchedulerLock的作用是保证当前定时任务的方法执行时获得锁，忽略其他相同任务的执行
    // name必须要指定，ShedLock就是根据这个name进行相同任务判定的
    // name：定时任务的名字，就是数据库中的主键(name)
    // lockAtMostFor：锁的最大时间单位为毫秒
    // lockAtLeastFor：锁的最小时间单位为毫秒

    
    @Scheduled(cron = "0/5 * * * * ? ")
    @SchedulerLock(name = "testJob1",lockAtLeastFor = "20000", lockAtMostFor = "30000")
    public void scheduledTask1() {
        log.info(Thread.currentThread().getName() + "->>>任务1执行第：" + (count++) + "次");
    }

    
    @Scheduled(cron = "0/5 * * * * ? ")
    @SchedulerLock(name = "testJob2")
    public void scheduledTask2() {
        log.info(Thread.currentThread().getName() + "->>>任务2执行第：" + (count++) + "次");
    }

}

1.6 主启动类


@SpringBootApplication
public class JdbcApplication {

    public static void main(String[] args) {
         SpringApplication.run(JdbcApplication.class, args);
    }

}