Quartz学习--二 Hello Quartz! 和源码分析

Quartz学习--二  Hello Quartz! 和源码分析



三.  Hello Quartz!


我会跟着 第一章 6.2 的图来 进行同步代码编写

  1. 简单入门示例:

    1. 创建一个新的java普通工程 引入对应版本jar包:

      jar包 maven地址为:

         <!-- Quartz jar 包 2.2.1 版本 -->
      <dependency>
      <groupId>org.quartz-scheduler</groupId>
      <artifactId>quartz</artifactId>
      <version>2.2.1</version>
      </dependency>
      <dependency>
      <groupId>org.quartz-scheduler</groupId>
      <artifactId>quartz-jobs</artifactId>
      <version>2.2.1</version>
      </dependency>
      <!-- 若你使用的框架是SpringBoot 需要引入:
      这里只是个示例简单程序 所以只需要导入上面两个的依赖就可
      -->
      <!--<dependency>-->
      <!--<groupId>org.springframework</groupId>-->
      <!--<artifactId>spring-context-support</artifactId>-->
      <!--<version>4.1.6.RELEASE</version>-->
      <!--</dependency>-->
    2. 自创建任务 (Job)

      仅仅需要对 org.quartz.Job 接口进行实现 将来调度器会执行我们重写的execute()方法

      package com.ws.quartzdemo1001.job01_HelloWorld;

      import org.quartz.Job;
      import org.quartz.JobExecutionContext;
      import org.quartz.JobExecutionException;
      import org.slf4j.Logger;
      import org.slf4j.LoggerFactory;

      /**
      * 实现 quartz 对使用人员开放的 Job接口
      */
      public class HelloJob implements Job {

      private static Logger log = LoggerFactory.getLogger(HelloJob.class);

      @Override
      public void execute(JobExecutionContext jobExecutionContext)
      throws JobExecutionException {
      log.info("Hello Quartz - Job");
      }
      }
      
      
    3. 编写使用Quartz的代码

      package com.ws.quartzdemo1001.job01_HelloWorld;

      import org.quartz.*;
      import org.quartz.impl.StdSchedulerFactory;
      import org.slf4j.Logger;
      import org.slf4j.LoggerFactory;
      import java.util.Date;

      public class HelloQuartz {
      private static Logger logger = LoggerFactory.getLogger(HelloQuartz.class);

      public static void main(String[] args) throws SchedulerException {
      // 1 创建 Scheduler 的工厂
      SchedulerFactory schedulerFactory = new StdSchedulerFactory();
      // 2 从工厂中获取调度器 的实例
      Scheduler scheduler = schedulerFactory.getScheduler();
      // 3 创建JobDetail
      JobDetail jobDetail = JobBuilder.newJob(HelloJob.class)
      .withDescription("this is my first job01_HelloWorld ") // 设置job相关描述
      .withIdentity("hello job01_HelloWorld" ,"normal job01_HelloWorld") // 设置任务 名称和组名
      .build(); //创建 JobDetail
      // 4 创建 trigger
      CronTrigger trigger = TriggerBuilder.newTrigger()
      .withDescription("this is my first trigger") //设置 trigger 相关描述
      .withIdentity("say hello trigger", "cron trigger") //设置 当前触发其 名字 和归属组名
      .startAt(new Date()) // 设置任务启动时间
      .withSchedule(CronScheduleBuilder.cronSchedule("0/10 * * * * ?"))
      .build();
      // 5 将 job01_HelloWorld 和 trigger 绑定 并注册到 调度器
      scheduler.scheduleJob(jobDetail,trigger);
      // 6 启动 调度器
      scheduler.start();
      logger.info(new Date() +" <<<<<< 启动");
      }
      }

      主要编写了:

      • 创建了Scheduler 工厂

      • 从工厂中获取调度器的实例

      • 使用自己实现了Job接口的类 来创建 JobDetail

      • 创建触发器 并指定触发规则

      • 将JobDetail 和触发器进行绑定放入 调度器中 (或者说注册到scheduler)

      • 启动调度器

    4. 执行结果:

    5. Quartz学习--二  Hello Quartz! 和源码分析

  1. 入门示例 (追根溯源)

  • 作为一个简单的应用程序 我们使用起来给我最大的感触就是 每个主要实例都有一个特定的创建方法

    比如 调度器实例就是依靠 Scheduler工厂而创建出来为我们使用

    JobDetail 和Trigger 亦是如此

  • HelloJob代码分析:

    接口: org.quartz.Job

    
    
    // Source code recreated from a .class file by IntelliJ IDEA
    // (powered by Fernflower decompiler)

    package org.quartz;

    public interface Job {
    void execute(JobExecutionContext context) throws JobExecutionException;
    }

    一个任务是一个实现Job接口的类, 且任务类必须含有空构造器

    当关联这个任务实例的触发器声明的执行时间到了的时候,调度程序Scheduler 会调用这个execute()方法来执行任务,我们的任务内容就可以在这个方法中执行

    JobExecutionContext: 工作执行的上下文 自动传入

    ​ 实际上在该方法退出之前会设置一个结果对象到 上下文中 ,

    ​ 来让JobListeners 或者TriggerListeners 获得当前任务执行的状态

    • HelloQuartz 代码分析:

       // 1 创建 Scheduler 的工厂
      SchedulerFactory schedulerFactory = new StdSchedulerFactory();

      创建一个生产调度器的工厂

      查看Scheduler 接口源码:

      // Source code recreated from a .class file by IntelliJ IDEA
      // (powered by Fernflower decompiler)

      package org.quartz;

      import java.util.Collection;

      public interface SchedulerFactory {
      Scheduler getScheduler() throws SchedulerException;

      Scheduler getScheduler(String var1) throws SchedulerException;

      Collection<Scheduler> getAllSchedulers() throws SchedulerException;
      }

      接口规范了 三个必须实现的方法:

      ​ 三个方法的作用实际上都是 来获取 调度器实例

      • getScheduler()

      • getScheduler(String schedName) // 返回指定了名字的调度器实例

      • getAllSchedulers()

      Scheduler 的实现有 两种:

      Quartz学习--二  Hello Quartz! 和源码分析Quartz学习--二  Hello Quartz! 和源码分析

      代码中创建的是 new StdSchedulerFactory() ;

      查看 DirectSchedulerFactory 中实现代码:

      
      
      public class DirectSchedulerFactory implements SchedulerFactory {
      public static final String DEFAULT_INSTANCE_ID = "SIMPLE_NON_CLUSTERED";
      public static final String DEFAULT_SCHEDULER_NAME = "SimpleQuartzScheduler";
      private static final boolean DEFAULT_JMX_EXPORT = false;
      private static final String DEFAULT_JMX_OBJECTNAME = null;
      private static final DefaultThreadExecutor DEFAULT_THREAD_EXECUTOR = new DefaultThreadExecutor();
      private static final int DEFAULT_BATCH_MAX_SIZE = 1;
      private static final long DEFAULT_BATCH_TIME_WINDOW = 0L;
      private boolean initialized = false;
      private static DirectSchedulerFactory instance = new DirectSchedulerFactory();
      private final Logger log = LoggerFactory.getLogger(this.getClass());

      protected Logger getLog() {
      return this.log;
      }

      protected DirectSchedulerFactory() {
      } ....

      仅从字面意思上理解 DirectSchedulerFactory 就是一个直接的 调度器创建工厂

      public static final String DEFAULT_INSTANCE_ID = "SIMPLE_NON_CLUSTERED";
      public static final String DEFAULT_SCHEDULER_NAME = "SimpleQuartzScheduler";

      开始两行中明确指明 这个直接的工厂 是没有实现分布式集群 而且预期返回 简单的调度器 实例

      再对比 StdSchedulerFactory的 源码:

      
      
      public class StdSchedulerFactory implements SchedulerFactory {
      public static final String PROPERTIES_FILE = "org.quartz.properties";
      public static final String PROP_SCHED_INSTANCE_NAME = "org.quartz.scheduler.instanceName";
      public static final String PROP_SCHED_INSTANCE_ID = "org.quartz.scheduler.instanceId";
      public static final String PROP_SCHED_INSTANCE_ID_GENERATOR_PREFIX = "org.quartz.scheduler.instanceIdGenerator";
      public static final String PROP_SCHED_INSTANCE_ID_GENERATOR_CLASS = "org.quartz.scheduler.instanceIdGenerator.class";
      public static final String PROP_SCHED_THREAD_NAME = "org.quartz.scheduler.threadName";
      public static final String PROP_SCHED_SKIP_UPDATE_CHECK = "org.quartz.scheduler.skipUpdateCheck";
      public static final String PROP_SCHED_BATCH_TIME_WINDOW = "org.quartz.scheduler.batchTriggerAcquisitionFireAheadTimeWindow";
      public static final String PROP_SCHED_MAX_BATCH_SIZE = "org.quartz.scheduler.batchTriggerAcquisitionMaxCount";
      public static final String PROP_SCHED_JMX_EXPORT = "org.quartz.scheduler.jmx.export";
      public static final String PROP_SCHED_JMX_OBJECT_NAME = "org.quartz.scheduler.jmx.objectName";
      public static final String PROP_SCHED_JMX_PROXY = "org.quartz.scheduler.jmx.proxy";
      public static final String PROP_SCHED_JMX_PROXY_CLASS = "org.quartz.scheduler.jmx.proxy.class";
      public static final String PROP_SCHED_RMI_EXPORT = "org.quartz.scheduler.rmi.export";
      public static final String PROP_SCHED_RMI_PROXY = "org.quartz.scheduler.rmi.proxy";
      public static final String PROP_SCHED_RMI_HOST = "org.quartz.scheduler.rmi.registryHost";
      public static final String PROP_SCHED_RMI_PORT = "org.quartz.scheduler.rmi.registryPort";
      public static final String PROP_SCHED_RMI_SERVER_PORT = "org.quartz.scheduler.rmi.serverPort";
      public static final String PROP_SCHED_RMI_CREATE_REGISTRY = "org.quartz.scheduler.rmi.createRegistry";
      public static final String PROP_SCHED_RMI_BIND_NAME = "org.quartz.scheduler.rmi.bindName";
      public static final String PROP_SCHED_WRAP_JOB_IN_USER_TX = "org.quartz.scheduler.wrapJobExecutionInUserTransaction";
      public static final String PROP_SCHED_USER_TX_URL = "org.quartz.scheduler.userTransactionURL";
      public static final String PROP_SCHED_IDLE_WAIT_TIME = "org.quartz.scheduler.idleWaitTime";
      public static final String PROP_SCHED_DB_FAILURE_RETRY_INTERVAL = "org.quartz.scheduler.dbFailureRetryInterval";
      public static final String PROP_SCHED_MAKE_SCHEDULER_THREAD_DAEMON = "org.quartz.scheduler.makeSchedulerThreadDaemon";
      public static final String PROP_SCHED_SCHEDULER_THREADS_INHERIT_CONTEXT_CLASS_LOADER_OF_INITIALIZING_THREAD = "org.quartz.scheduler.threadsInheritContextClassLoaderOfInitializer";
      public static final String PROP_SCHED_CLASS_LOAD_HELPER_CLASS = "org.quartz.scheduler.classLoadHelper.class";
      public static final String PROP_SCHED_JOB_FACTORY_CLASS = "org.quartz.scheduler.jobFactory.class";
      public static final String PROP_SCHED_JOB_FACTORY_PREFIX = "org.quartz.scheduler.jobFactory";
      public static final String PROP_SCHED_INTERRUPT_JOBS_ON_SHUTDOWN = "org.quartz.scheduler.interruptJobsOnShutdown";
      public static final String PROP_SCHED_INTERRUPT_JOBS_ON_SHUTDOWN_WITH_WAIT = "org.quartz.scheduler.interruptJobsOnShutdownWithWait";
      public static final String PROP_SCHED_CONTEXT_PREFIX = "org.quartz.context.key";
      public static final String PROP_THREAD_POOL_PREFIX = "org.quartz.threadPool";
      public static final String PROP_THREAD_POOL_CLASS = "org.quartz.threadPool.class";
      public static final String PROP_JOB_STORE_PREFIX = "org.quartz.jobStore";
      public static final String PROP_JOB_STORE_LOCK_HANDLER_PREFIX = "org.quartz.jobStore.lockHandler";
      public static final String PROP_JOB_STORE_LOCK_HANDLER_CLASS = "org.quartz.jobStore.lockHandler.class";
      public static final String PROP_TABLE_PREFIX = "tablePrefix";
      public static final String PROP_SCHED_NAME = "schedName";
      public static final String PROP_JOB_STORE_CLASS = "org.quartz.jobStore.class";
      public static final String PROP_JOB_STORE_USE_PROP = "org.quartz.jobStore.useProperties";
      public static final String PROP_DATASOURCE_PREFIX = "org.quartz.dataSource";
      public static final String PROP_CONNECTION_PROVIDER_CLASS = "connectionProvider.class";
        .....
        

      看起来明显区别是相对于 简单的调度器实例来说 它多出了好多常量

      从常量: PROPERTIES_FILE 中可以看出 它实际上是 对应的一个配置

      我们再返回去查看 第一章 .7 的properties 配置文件中的 可以配置的属性

      不难发现 其实我们可以设置的配置 再quartz的声明处 就在 这里

      它为我们创建了的调度器实现了各种复杂模式

      作为初始demo我现在不再深入它的具体实现

      继续进行代码分析:

      
      

      这里我们使用了 JobBulider 返回的是 JobDetail

      使用JobBulider 的newJob 方法 将 我们自实现的工作类当做参数传入

      追溯源码:

      ​public class JobBuilder {
      private JobKey key;
      private String description;
      private Class<? extends Job> jobClass;
      private boolean durability;
      private boolean shouldRecover;
      private JobDataMap jobDataMap = new JobDataMap();
      ...
      protected JobBuilder() {
      }
      public static JobBuilder newJob() {
      return new JobBuilder();
      }
      public static JobBuilder newJob(Class<? extends Job> jobClass) {
      JobBuilder b = new JobBuilder();
      b.ofType(jobClass);
      return b;
      }
      ...
      public JobBuilder ofType(Class<? extends Job> jobClazz) {
      this.jobClass = jobClazz;
      return this;
      }
      ...
      • 发现 JobBuilder 的静态方法中 实例了一个 JobBuilder的对象

      • 并调用了 ofType 将我们传入的自实现的工作类设置成这个对象的 成员属性

      • 再看 构造器 权限是 protected

      看上去感觉像是 单例模式 不能直接创建 对象~!!! 而是提供一个静态方法 返回一个当前类的一个实例

      区别就是 这个方法是个有参数的调用

      ok 我们现在就深入了解到这里 jobClass 具体什么时候使用 我们慢慢探索

      总体看起来 JobBuilder只是一个 充满 附加参数的 而且封装了Job的Pojo一样

      继续代码分析 发现:

      .withDescription("this is my first job01_HelloWorld ")  // 设置job相关描述

      没有什么可以赘述

       .withIdentity("hello job01_HelloWorld" ,"normal job01_HelloWorld") // 设置任务 名称和组名

      看一下 设置身份 它传入了两个 参数

      源码查看:

          public JobBuilder withIdentity(String name, String group) {
      this.key = new JobKey(name, group);
      return this;
      }

      翻看 JobKey 和Key<JobKey>的源码 :

      public class Key<T> implements Serializable, Comparable<Key<T>> {
      private static final long serialVersionUID = -7141167957642391350L;
      public static final String DEFAULT_GROUP = "DEFAULT";
      private final String name;
      private final String group;
      ...
      public static String createUniqueName(String group) {
      if (group == null) {
      group = "DEFAULT";
      }

      String n1 = UUID.randomUUID().toString();
      String n2 = UUID.nameUUIDFromBytes(group.getBytes()).toString();
      return String.format("%s-%s", n2.substring(24), n1);
      }

      实际上他只是为了达到 唯一的生成名称而创建的一个数据结构

      继续 再看:

      .build(); //创建 JobDetail

      源码:

      public JobDetail build() {
      JobDetailImpl job = new JobDetailImpl();
      job.setJobClass(this.jobClass);
      job.setDescription(this.description);
      if (this.key == null) {
      this.key = new JobKey(Key.createUniqueName((String)null), (String)null);
      }

      job.setKey(this.key);
      job.setDurability(this.durability);
      job.setRequestsRecovery(this.shouldRecover);
      if (!this.jobDataMap.isEmpty()) {
      job.setJobDataMap(this.jobDataMap);
      }

      return job;
      }

      创建了 JobDetail的一个子类 它的名字 (JobDetailImpl) 说明的是 JobDetail的一个实现

      他这样做的目的: 实际上 Quartz 只提供给我们 JobDetail里的一些可以用户自定义的属性设置接口 其他的Quartz负责了自动组装

      继续 分析代码:

      
      
       CronTrigger trigger = TriggerBuilder.newTrigger()
      .withDescription("this is my first trigger") //设置 trigger 相关描述
      .withIdentity("say hello trigger", "cron trigger") //设置 当前触发其 名字 和归属组名
      .startAt(new Date()) // 设置任务启动时间
      .withSchedule(CronScheduleBuilder.cronSchedule("0/10 * * * * ?"))
      .build();

      翻看后发现与Job创建大同小异 不再赘述

      继续 分析代码 scheduleJob():

       scheduler.scheduleJob(jobDetail,trigger);

      我们一直翻看 StdScheduler 的实现 跟踪主要方法:

      跟踪到了QuartzScheduler 类中

      查看QuartzScheduler所属包名: package org.quartz.core;

      ok~ 到了核心类@!@

      package org.quartz.core;
      ...
      public class QuartzScheduler implements RemotableQuartzScheduler {
      ...
      public Date scheduleJob(JobDetail jobDetail, Trigger trigger) throws SchedulerException {
      this.validateState();
      if (jobDetail == null) {
      throw new SchedulerException("JobDetail cannot be null");
      } else if (trigger == null) {
      throw new SchedulerException("Trigger cannot be null");
      } else if (jobDetail.getKey() == null) {
      throw new SchedulerException("Job's key cannot be null");
      } else if (jobDetail.getJobClass() == null) {
      throw new SchedulerException("Job's class cannot be null");
      } else {
      OperableTrigger trig = (OperableTrigger)trigger;
      if (trigger.getJobKey() == null) {
      trig.setJobKey(jobDetail.getKey());
      } else if (!trigger.getJobKey().equals(jobDetail.getKey())) {
      throw new SchedulerException("Trigger does not reference given job!");
      }

      trig.validate();//验证trigger
      Calendar cal = null;
      if (trigger.getCalendarName() != null) {
      cal = this.resources.getJobStore().retrieveCalendar(trigger.getCalendarName());
      }

      Date ft = trig.computeFirstFireTime(cal);
      if (ft == null) {
      throw new SchedulerException("Based on configured schedule, the given trigger '" + trigger.getKey() + "' will never fire.");
      } else {
      this.resources.getJobStore().storeJobAndTrigger(jobDetail, trig);
      this.notifySchedulerListenersJobAdded(jobDetail);
      this.notifySchedulerThread(trigger.getNextFireTime().getTime());
      this.notifySchedulerListenersSchduled(trigger);
      return ft;
      }
      }
      }

      一系列非空判断之后 有如下几行 :

       OperableTrigger trig = (OperableTrigger)trigger;
      trig.setJobKey(jobDetail.getKey());
      ...
      if (trigger.getCalendarName() != null) {
      cal = this.resources.getJobStore().retrieveCalendar(trigger.getCalendarName());
      }

      Date ft = trig.computeFirstFireTime(cal);
      this.resources.getJobStore().storeJobAndTrigger(jobDetail, trig);
      this.notifySchedulerListenersJobAdded(jobDetail);
      this.notifySchedulerThread(trigger.getNextFireTime().getTime());
      this.notifySchedulerListenersSchduled(trigger);
      return ft;
      • 第一步 对一个触发器 设置了 JobKey 实际上就绑定了 trigger和job之间的关系

      • 第二步 获取jobStore 翻看源码时 翻看 RAMJobStore 的retrieveCalendar()方法实现

      其实这里还没涉及到多个calendar 它的作用就是获取指定名称的日历

      • 第三步 获取第一次触发的时间

        在触发器首次添加到调度程序时由调度程序调用,以便让触发器基于任何关联的日历计算其第一次触发时间。调用此方法后,getNextFireTime() 应返回有效的答案。

      • 第四步 "存储" 注册到JobStore

        通知调度器ListenersJob 添加 Job

      通知调度器线程 下次调用时间

      通知调度器工作安排

      ok ~ 其实 我们可以简单理解 主要作用就是将 trgger和job绑定 然后 quartz又通知了它的各个核心组件

      源码中:

      
      
      this.resources.getJobStore().storeJobAndTrigger(jobDetail, trig);

      追溯到JobStore 发现他有几个实现:Quartz学习--二  Hello Quartz! 和源码分析

    • Quartz学习--二  Hello Quartz! 和源码分析

      "存储" 注册到JobStore的 方式区别也就在这里托盘而出:

      因为我们是RAMJobStore 我们查看源代码:

      public class RAMJobStore implements JobStore {
      ...
      public void storeJob(JobDetail newJob, boolean replaceExisting) throws ObjectAlreadyExistsException {
      JobWrapper jw = new JobWrapper((JobDetail)newJob.clone());
      boolean repl = false;
      Object var5 = this.lock;
      synchronized(this.lock) {
      if (this.jobsByKey.get(jw.key) != null) {
      if (!replaceExisting) {
      throw new ObjectAlreadyExistsException(newJob);
      }

      repl = true;
      }

      if (!repl) {
      HashMap<JobKey, JobWrapper> grpMap = (HashMap)this.jobsByGroup.get(newJob.getKey().getGroup());
      if (grpMap == null) {
      grpMap = new HashMap(100);
      this.jobsByGroup.put(newJob.getKey().getGroup(), grpMap);
      }

      grpMap.put(newJob.getKey(), jw);
      this.jobsByKey.put(jw.key, jw);
      } else {
      JobWrapper orig = (JobWrapper)this.jobsByKey.get(jw.key);
      orig.jobDetail = jw.jobDetail;
      }

      }
      }
      
      

      它的实现是把内容放在了 一个Map中维护了 所以说再重启之后 这个map 并没有持久化到硬盘中 它的生命周期就在jvm关闭时丢失了

      再看一个不完全实现:

      public abstract class JobStoreSupport implements JobStore, Constants {
      ...
      public void storeJobAndTrigger(final JobDetail newJob, final OperableTrigger newTrigger) throws JobPersistenceException {
      this.executeInLock(this.isLockOnInsert() ? "TRIGGER_ACCESS" : null, new JobStoreSupport.VoidTransactionCallback() {
      public void executeVoid(Connection conn) throws JobPersistenceException {
      JobStoreSupport.this.storeJob(conn, newJob, false);
      JobStoreSupport.this.storeTrigger(conn, newTrigger, newJob, false, "WAITING", false, false);
      }
      });
      }
      ...
      protected void storeJob(Connection conn, JobDetail newJob, boolean replaceExisting) throws JobPersistenceException {
      boolean existingJob = this.jobExists(conn, newJob.getKey());

      try {
      if (existingJob) {
      if (!replaceExisting) {
      throw new ObjectAlreadyExistsException(newJob);
      }

      this.getDelegate().updateJobDetail(conn, newJob);
      } else {
      this.getDelegate().insertJobDetail(conn, newJob);
      }

      } catch (IOException var6) {
      throw new JobPersistenceException("Couldn't store job: " + var6.getMessage(), var6);
      } catch (SQLException var7) {
      throw new JobPersistenceException("Couldn't store job: " + var7.getMessage(), var7);
      }
      }
      ...
      protected void storeTrigger(Connection conn, OperableTrigger newTrigger, JobDetail job, boolean replaceExisting, String state, boolean forceState, boolean recovering) throws JobPersistenceException {
      boolean existingTrigger = this.triggerExists(conn, newTrigger.getKey());
      if (existingTrigger && !replaceExisting) {
      throw new ObjectAlreadyExistsException(newTrigger);
      } else {
      try {
      if (!forceState) {
      boolean shouldBepaused = this.getDelegate().isTriggerGroupPaused(conn, newTrigger.getKey().getGroup());
      if (!shouldBepaused) {
      shouldBepaused = this.getDelegate().isTriggerGroupPaused(conn, "_$_ALL_GROUPS_PAUSED_$_");
      if (shouldBepaused) {
      this.getDelegate().insertPausedTriggerGroup(conn, newTrigger.getKey().getGroup());
      }
      }

      if (shouldBepaused && (state.equals("WAITING") || state.equals("ACQUIRED"))) {
      state = "PAUSED";
      }
      }

      if (job == null) {
      job = this.getDelegate().selectJobDetail(conn, newTrigger.getJobKey(), this.getClassLoadHelper());
      }

      if (job == null) {
      throw new JobPersistenceException("The job (" + newTrigger.getJobKey() + ") referenced by the trigger does not exist.");
      } else {
      if (job.isConcurrentExectionDisallowed() && !recovering) {
      state = this.checkBlockedState(conn, job.getKey(), state);
      }

      if (existingTrigger) {
      this.getDelegate().updateTrigger(conn, newTrigger, state, job);
      } else {
      this.getDelegate().insertTrigger(conn, newTrigger, state, job);
      }

      }
      } catch (Exception var10) {
      throw new JobPersistenceException("Couldn't store trigger '" + newTrigger.getKey() + "' for '" + newTrigger.getJobKey() + "' job:" + var10.getMessage(), var10);
      }
      }
      }

      其中的updateJobDetail 翻看源码实际上是将内容存储到了 数据库中

      这其实就是jdbc 方式的原理

      现在话题拉回来

      继续 分析代码:

      我们完成了所有的创建注册绑定操作 万事俱备只欠东风了

      启动:

      // 6 启动 调度器
      scheduler.start();

      源码:

      public void start() throws SchedulerException {
      if (!this.shuttingDown && !this.closed) {
      this.notifySchedulerListenersStarting();
      if (this.initialStart == null) {
      this.initialStart = new Date();
      this.resources.getJobStore().schedulerStarted();
      this.startPlugins();
      } else {
      this.resources.getJobStore().schedulerResumed();
      }

      this.schedThread.togglePause(false);//设置 不暂停
      this.getLog().info("Scheduler " + this.resources.getUniqueIdentifier() + " started.");
      this.notifySchedulerListenersStarted();// 提醒 调度器的监听 启动
      } else {
      throw new SchedulerException("The Scheduler cannot be restarted after shutdown() has been called.");
      }
      }

      初始化JobStore源码分析:

              // 判断初始化标识    保证jobStore
      if (this.initialStart == null) { // 没有初始化过: 进行初始化
      this.initialStart = new Date();
      this.resources.getJobStore().schedulerStarted();
      this.startPlugins();
      } else { // 已经初始化过 进行 恢复
      this.resources.getJobStore().schedulerResumed();
      }
      public abstract class JobStoreSupport implements JobStore, Constants {
      ...
      public void schedulerStarted() throws SchedulerException {
      if (this.isClustered()) {//判断是否是是集群
      this.clusterManagementThread = new JobStoreSupport.ClusterManager();
      if (this.initializersLoader != null) {
      this.clusterManagementThread.setContextClassLoader(this.initializersLoader);
      }

      this.clusterManagementThread.initialize();
      } else { // 不是集群的话
      try {
      this.recoverJobs();// 恢复 工作
      } catch (SchedulerException var2) {
      throw new SchedulerConfigException("Failure occured during job recovery.", var2);
      }
      }

      this.misfireHandler = new JobStoreSupport.MisfireHandler();
      if (this.initializersLoader != null) {
      this.misfireHandler.setContextClassLoader(this.initializersLoader);
      }

      this.misfireHandler.initialize();
      this.schedulerRunning = true;
      this.getLog().debug("JobStore background threads started (as scheduler was started).");
      }
      ...
      // 恢复 工作:
      // 将恢复任何失败的工作和丢失了触发的工作,并根据需要清理数据存储
      protected void recoverJobs() throws JobPersistenceException {
      this.executeInNonManagedTXLock("TRIGGER_ACCESS", new JobStoreSupport.VoidTransactionCallback() {
      public void executeVoid(Connection conn) throws JobPersistenceException {
      JobStoreSupport.this....(conn);//恢复job
      }
      }, (JobStoreSupport.TransactionValidator)null);
      }
      ... protected void recoverJobs(Connection conn) throws JobPersistenceException {
      try {
      int rows = this.getDelegate().updateTriggerStatesFromOtherStates(conn, "WAITING", "ACQUIRED", "BLOCKED");
      rows += this.getDelegate().updateTriggerStatesFromOtherStates(conn, "PAUSED", "PAUSED_BLOCKED", "PAUSED_BLOCKED");
      this.getLog().info("Freed " + rows + " triggers from 'acquired' / 'blocked' state.");
      this.recoverMisfiredJobs(conn, true);
      List<OperableTrigger> recoveringJobTriggers = this.getDelegate().selectTriggersForRecoveringJobs(conn);
      this.getLog().info("Recovering " + recoveringJobTriggers.size() + " jobs that were in-progress at the time of the last shut-down.");
      Iterator i$ = recoveringJobTriggers.iterator();

      while(i$.hasNext()) {
      OperableTrigger recoveringJobTrigger = (OperableTrigger)i$.next();
      if (this.jobExists(conn, recoveringJobTrigger.getJobKey())) {
      recoveringJobTrigger.computeFirstFireTime((Calendar)null);
      this.storeTrigger(conn, recoveringJobTrigger, (JobDetail)null, false, "WAITING", false, true);
      }
      }

      this.getLog().info("Recovery complete.");
      List<TriggerKey> cts = this.getDelegate().selectTriggersInState(conn, "COMPLETE");
      Iterator i$ = cts.iterator();

      while(i$.hasNext()) {
      TriggerKey ct = (TriggerKey)i$.next();
      this.removeTrigger(conn, ct);
      }

      this.getLog().info("Removed " + cts.size() + " 'complete' triggers.");
      int n = this.getDelegate().deleteFiredTriggers(conn);
      this.getLog().info("Removed " + n + " stale fired job entries.");
      } catch (JobPersistenceException var7) {
      throw var7;
      } catch (Exception var8) {
      throw new JobPersistenceException("Couldn't recover jobs: " + var8.getMessage(), var8);
      }
      }
        

      初始JobStore时 恢复相关: 将 失败标识的 或者 丢失触发的 工作 进行一个找回 并设置到 调度器触发工作日程中

      分析:

        this.schedThread.togglePause(false);

      探索:

       // 设置主处理循环在下一个可能的点暂停。
      void togglePause(boolean pause) {
      Object var2 = this.sigLock;
      synchronized(this.sigLock) {
      this.paused = pause;
      if (this.paused) {
      this.signalSchedulingChange(0L);
      } else {
      this.sigLock.notifyAll(); // 唤醒所有等待线程
      }

      }
      }
      ...
      //通知主要处理循环,已经进行了调度的改变
      public void signalSchedulingChange(long candidateNewNextFireTime) {
      Object var3 = this.sigLock;
      synchronized(this.sigLock) {
      this.signaled = true;
      this.signaledNextFireTime = candidateNewNextFireTime;
      this.sigLock.notifyAll();//中断在等待时间到达时可能发生的任何睡眠线程
      }
      }
上一篇:隐藏tabControl的标签


下一篇:[转]Dll注入经典方法完整版