版本：3.1.0-SNAPSHOT

git地址： https://github.com/apache/shardingsphere-elasticjob

 

Maven 坐标

<dependency>
    <groupId>org.apache.shardingsphere.elasticjob</groupId>
    <artifactId>elasticjob-lite-spring-boot-starter</artifactId>
    <version>${latest.version}</version>
</dependency>

 

Spring.factories配置

org.springframework.boot.autoconfigure.EnableAutoConfiguration=\
  org.apache.shardingsphere.elasticjob.lite.spring.boot.job.ElasticJobLiteAutoConfiguration

在添加elasticjob-lite-spring-boot-starter启动类的时候，会自动加载ElasticJobLiteAutoConfiguration，接下来看下ElasticJobLiteAutoConfiguration中所做的处理。

 

ElasticJobLiteAutoConfiguration.java

/**
 * ElasticJob-Lite auto configuration.
 */
@Configuration(proxyBeanMethods = false)
@AutoConfigureAfter(DataSourceAutoConfiguration.class)


/**
 * elastic job 开关
 * elasticjob.enabled.ture默认为true
 */
@ConditionalOnProperty(name = "elasticjob.enabled", havingValue = "true", matchIfMissing = true)


/**
 * 导入
 * ElasticJobRegistryCenterConfiguration.class 注册中心配置
 * ElasticJobTracingConfiguration.class job事件追踪配置
 * ElasticJobSnapshotServiceConfiguration.class 快照配置
 */
@Import({ElasticJobRegistryCenterConfiguration.class, ElasticJobTracingConfiguration.class, ElasticJobSnapshotServiceConfiguration.class})


/**
 * job相关配置信息
 */
@EnableConfigurationProperties(ElasticJobProperties.class)
public class ElasticJobLiteAutoConfiguration {
    
    @Configuration(proxyBeanMethods = false)
    /**
     * ElasticJobBootstrapConfiguration.class  创建job beans 注入spring容器
     * ScheduleJobBootstrapStartupRunner.class  执行类型为ScheduleJobBootstrap.class 的job开始运行
     */
    @Import({ElasticJobBootstrapConfiguration.class, ScheduleJobBootstrapStartupRunner.class})
    protected static class ElasticJobConfiguration {
    }
}

Elastic-job 是利用zookeeper 实现分布式job的功能，所以在自动装配的时候，需要有zookeeper注册中心的配置。

自动装配主要做了4件事事

1.配置zookeeper 客户端信息，启动连接zookeeper.

2.配置事件追踪数据库，用于保存job运行记录

3.解析所有job配置文件，将所有job的bean放置在spring 单例bean中

4.识别job类型，在zookeeper节点上处理job节点数据，运行定时任务job.

 

第一件事：配置zookeeper 客户端信息，启动连接zookeeper.

ZookeeperRegistryCenter.class

public void init() {
    log.debug("Elastic job: zookeeper registry center init, server lists is: {}.", zkConfig.getServerLists());
    CuratorFrameworkFactory.Builder builder = CuratorFrameworkFactory.builder()
            //设置zookeeper 服务器地址
            .connectString(zkConfig.getServerLists())
            //设置重试机制
            .retryPolicy(new ExponentialBackoffRetry(zkConfig.getBaseSleepTimeMilliseconds(), zkConfig.getMaxRetries(), zkConfig.getMaxSleepTimeMilliseconds()))
            //设置命名空间，zookeeper节点名称
            .namespace(zkConfig.getNamespace());
    //设置session超时时间
    if (0 != zkConfig.getSessionTimeoutMilliseconds()) {
        builder.sessionTimeoutMs(zkConfig.getSessionTimeoutMilliseconds());
    }
    //设置连接超时时间
    if (0 != zkConfig.getConnectionTimeoutMilliseconds()) {
        builder.connectionTimeoutMs(zkConfig.getConnectionTimeoutMilliseconds());
    }
    if (!Strings.isNullOrEmpty(zkConfig.getDigest())) {
        builder.authorization("digest", zkConfig.getDigest().getBytes(StandardCharsets.UTF_8))
                .aclProvider(new ACLProvider() {
                
                    @O