SpringBoot2.0.3之quartz集成，不是你想的那样哦！

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作者：青石路

cnblogs.com/youzhibing/p/10024558.html

java定时任务调度的实现方式　

Timer

这个相信大家都有用过，我也用过，但用的不多；

特点是：简单易用，但由于所有任务都是由同一个线程来调度，因此所有任务都是串行执行的，同一时间只能有一个任务在执行，前一个任务的延迟或异常都将会影响到之后的任务；能实现简单的定时任务，稍微复杂点（或要求高一些）的定时任务却不好实现。

ScheduledExecutor

这个我相信大家也都用过，而且用的比Timer多；正是鉴于Timer的缺陷，Java 5推出了基于线程池设计的ScheduledExecutor；

特点：每一个被调度的任务都会由线程池中一个线程去执行，因此任务是并发执行的，相互之间不会受到干扰。需要注意的是，只有当任务的执行时间到来时，ScheduedExecutor 才会真正启动一个线程，其余时间 ScheduledExecutor 都是在轮询任务的状态。

虽然用ScheduledExecutor和Calendar能够实现复杂任务调度，但实现起来还是比较麻烦，对开发还是不够友善。

Spring Scheduler

spring对任务调度的实现支持，可以指定任务的执行时间，但对任务队列和线程池的管控较弱；一般集成于项目中，小任务很方便。

JCronTab

JCronTab则是一款完全按照crontab语法编写的java任务调度工具。

特点：

可指定任务的执行时间；
提供完全按照Unix的UNIX-POSIX crontab的格式来规定时间；
支持多种任务调度的持久化方法，包括普通文件、数据库以及 XML 文件进行持久化；
JCronTab内置了发邮件功能，可以将任务执行结果方便地发送给需要被通知的人；
设计和部署是高性能并可扩展。

Quartz

本文主角，请往下看

当然还有XXL-JOB、Elastic-Job、Saturn等等

quartz相关概念

Scheduler：调度器，进行任务调度；quartz的大脑
Job：业务job，亦可称业务组件；定时任务的具体执行业务需要实现此接口，调度器会调用此接口的execute方法完成我们的定时业务
JobDetail：用来定义业务Job的实例，我们可以称之为quartz job，很多时候我们谈到的job指的是JobDetail
Trigger：触发器，用来定义一个指定的Job何时被执行
JobBuilder：Job构建器，用来定义或创建JobDetail的实例；JobDetail限定了只能是Job的实例
TriggerBuilder：触发器构建器，用来定义或创建触发器的实例

具体为什么要分这么细，大家可以去查阅下相关资料，你会发现很多东西。

工程实现

pom.xml

<?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.lee</groupId><artifactId>spring-boot-quartz</artifactId><version>1.0-SNAPSHOT</version><properties><java.version>1.8</java.version><maven.compiler.source>1.8</maven.compiler.source><maven.compiler.target>1.8</maven.compiler.target><druid.version>1.1.10</druid.version><pagehelper.version>1.2.5</pagehelper.version><druid.version>1.1.10</druid.version></properties><parent><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-parent</artifactId><version>2.0.3.RELEASE</version></parent><dependencies><dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-web</artifactId></dependency><dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-thymeleaf</artifactId></dependency><dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-quartz</artifactId></dependency><dependency><groupId>com.alibaba</groupId><artifactId>druid-spring-boot-starter</artifactId><version>${druid.version}</version></dependency><dependency><groupId>mysql</groupId><artifactId>mysql-connector-java</artifactId></dependency><dependency><groupId>com.github.pagehelper</groupId><artifactId>pagehelper-spring-boot-starter</artifactId><version>${pagehelper.version}</version></dependency><!-- 日志 --><dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-logging</artifactId><exclusions>            <!-- 排除spring-boot-starter-logging中的全部依赖 --><exclusion><groupId>*</groupId><artifactId>*</artifactId></exclusion></exclusions><scope>test</scope>     <!-- 打包的时候不打spring-boot-starter-logging.jar --></dependency><dependency><groupId>ch.qos.logback</groupId><artifactId>logback-classic</artifactId></dependency><dependency><groupId>org.projectlombok</groupId><artifactId>lombok</artifactId><optional>true</optional></dependency></dependencies><build><finalName>spring-boot-quartz</finalName><plugins><!-- 打包项目 mvn clean package --><plugin><groupId>org.springframework.boot</groupId><artifactId>spring-boot-maven-plugin</artifactId></plugin></plugins></build>
</project>

application.xml

server:port: 9001servlet:context-path: /quartz
spring:thymeleaf:mode: HTMLcache: false#连接池配置datasource:type: com.alibaba.druid.pool.DruidDataSourcedruid:driver-class-name: com.mysql.jdbc.Driverurl: jdbc:mysql://localhost:3306/spring-boot-quartz?useSSL=false&useUnicode=trueusername: rootpassword: 123456initial-size: 1                     #连接池初始大小max-active: 20                      #连接池中最大的活跃连接数min-idle: 1                         #连接池中最小的活跃连接数max-wait: 60000                     #配置获取连接等待超时的时间pool-prepared-statements: true    #打开PSCache，并且指定每个连接上PSCache的大小max-pool-prepared-statement-per-connection-size: 20validation-query: SELECT 1 FROM DUALvalidation-query-timeout: 30000test-on-borrow: false             #是否在获得连接后检测其可用性test-on-return: false             #是否在连接放回连接池后检测其可用性test-while-idle: true             #是否在连接空闲一段时间后检测其可用性quartz:#相关属性配置properties:org:quartz:scheduler:instanceName: quartzSchedulerinstanceId: AUTOjobStore:class: org.quartz.impl.jdbcjobstore.JobStoreTXdriverDelegateClass: org.quartz.impl.jdbcjobstore.StdJDBCDelegatetablePrefix: QRTZ_isClustered: falseclusterCheckinInterval: 10000useProperties: falsethreadPool:class: org.quartz.simpl.SimpleThreadPoolthreadCount: 10threadPriority: 5threadsInheritContextClassLoaderOfInitializingThread: true#数据库方式job-store-type: JDBC#初始化表结构jdbc:initialize-schema: NEVER
#mybatis配置
mybatis:type-aliases-package: com.lee.quartz.entitymapper-locations: classpath:mybatis/mapper/*.xml
#分页配置, pageHelper是物理分页插件
pagehelper:#4.0.0以后版本可以不设置该参数，该示例中是5.1.4helper-dialect: mysql#启用合理化，如果pageNum<1会查询第一页，如果pageNum>pages会查询最后一页reasonable: true
logging:level:com.lee.quartz.mapper: debug

这样，quartz就配置好了，应用里面直接用即可

JobController.java

package com.lee.quartz.web;import com.github.pagehelper.PageInfo;
import com.lee.quartz.common.Result;
import com.lee.quartz.entity.QuartzJob;
import com.lee.quartz.service.IJobService;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;@RestController
@RequestMapping("/job")
public class JobController {private final static Logger LOGGER = LoggerFactory.getLogger(JobController.class);@Autowiredprivate IJobService jobService;@SuppressWarnings({ "unchecked", "rawtypes" })@PostMapping("/add")public Result save(QuartzJob quartz){LOGGER.info("新增任务");Result result = jobService.saveJob(quartz);return result;}@PostMapping("/list")public PageInfo list(String jobName,Integer pageNo,Integer pageSize){LOGGER.info("任务列表");PageInfo pageInfo = jobService.listQuartzJob(jobName, pageNo, pageSize);return pageInfo;}@PostMapping("/trigger")public  Result trigger(String jobName, String jobGroup) {LOGGER.info("触发任务");Result result = jobService.triggerJob(jobName, jobGroup);return result;}@PostMapping("/pause")public  Result pause(String jobName, String jobGroup) {LOGGER.info("停止任务");Result result = jobService.pauseJob(jobName, jobGroup);return result;}@PostMapping("/resume")public  Result resume(String jobName, String jobGroup) {LOGGER.info("恢复任务");Result result = jobService.resumeJob(jobName, jobGroup);return result;}@PostMapping("/remove")public  Result remove(String jobName, String jobGroup) {LOGGER.info("移除任务");Result result = jobService.removeJob(jobName, jobGroup);return result;}
}

JobServiceImpl.java

package com.lee.quartz.service.impl;import com.github.pagehelper.PageHelper;
import com.github.pagehelper.PageInfo;
import com.lee.quartz.common.Result;
import com.lee.quartz.entity.QuartzJob;
import com.lee.quartz.mapper.JobMapper;
import com.lee.quartz.service.IJobService;
import org.quartz.*;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;import java.util.List;@Service
public class JobServiceImpl implements IJobService {@Autowiredprivate Scheduler scheduler;@Autowiredprivate JobMapper jobMapper;@Overridepublic PageInfo listQuartzJob(String jobName, Integer pageNum, Integer pageSize) {PageHelper.startPage(pageNum, pageSize);List<QuartzJob> jobList = jobMapper.listJob(jobName);PageInfo pageInfo = new PageInfo(jobList);return pageInfo;}@Overridepublic Result saveJob(QuartzJob quartz){try {//如果是修改  展示旧的 任务if(quartz.getOldJobGroup() != null && !"".equals(quartz.getOldJobGroup())){JobKey key = new JobKey(quartz.getOldJobName(),quartz.getOldJobGroup());scheduler.deleteJob(key);}//构建job信息Class cls = Class.forName(quartz.getJobClassName()) ;cls.newInstance();JobDetail job = JobBuilder.newJob(cls).withIdentity(quartz.getJobName(),quartz.getJobGroup()).withDescription(quartz.getDescription()).build();// 触发时间点CronScheduleBuilder cronScheduleBuilder = CronScheduleBuilder.cronSchedule(quartz.getCronExpression().trim());Trigger trigger = TriggerBuilder.newTrigger().withIdentity("trigger"+quartz.getJobName(), quartz.getJobGroup()).startNow().withSchedule(cronScheduleBuilder).build();//交由Scheduler安排触发scheduler.scheduleJob(job, trigger);} catch (Exception e) {e.printStackTrace();return Result.error();}return Result.ok();}@Overridepublic Result triggerJob(String jobName, String jobGroup) {JobKey key = new JobKey(jobName,jobGroup);try {scheduler.triggerJob(key);} catch (SchedulerException e) {e.printStackTrace();return Result.error();}return Result.ok();}@Overridepublic Result pauseJob(String jobName, String jobGroup) {JobKey key = new JobKey(jobName,jobGroup);try {scheduler.pauseJob(key);} catch (SchedulerException e) {e.printStackTrace();return Result.error();}return Result.ok();}@Overridepublic Result resumeJob(String jobName, String jobGroup) {JobKey key = new JobKey(jobName,jobGroup);try {scheduler.resumeJob(key);} catch (SchedulerException e) {e.printStackTrace();return Result.error();}return Result.ok();}@Overridepublic Result removeJob(String jobName, String jobGroup) {try {TriggerKey triggerKey = TriggerKey.triggerKey(jobName, jobGroup);// 停止触发器scheduler.pauseTrigger(triggerKey);// 移除触发器scheduler.unscheduleJob(triggerKey);// 删除任务scheduler.deleteJob(JobKey.jobKey(jobName, jobGroup));System.out.println("removeJob:"+JobKey.jobKey(jobName));} catch (Exception e) {e.printStackTrace();return Result.error();}return Result.ok();}
}

主要就是以上文件，详情请查看spring-boot-quartz

https://gitee.com/youzhibing/spring-boot-2.0.3/tree/master/spring-boot-quartz

工程里面数据源用的druid，springboot默认也会将该数据源应用到quartz，如果想给quartz单独配置数据源，可配合@QuartzDataSource来实现

最终效果如下

trigger状态

org.quartz.impl.jdbcjobstore.Constants中存放了一些列的常量，源代码如下

/* * All content copyright Terracotta, Inc., unless otherwise indicated. All rights reserved.* * Licensed under the Apache License, Version 2.0 (the "License"); you may not * use this file except in compliance with the License. You may obtain a copy * of the License at * *   http://www.apache.org/licenses/LICENSE-2.0 *   * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the * License for the specific language governing permissions and limitations * under the License.* */package org.quartz.impl.jdbcjobstore;/*** <p>* This interface can be implemented by any <code>{@link* org.quartz.impl.jdbcjobstore.DriverDelegate}</code>* class that needs to use the constants contained herein.* </p>* * @author <a href="mailto:jeff@binaryfeed.org">Jeffrey Wescott</a>* @author James House*/
public interface Constants {/** ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~* * Constants.* * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~*/// Table namesString TABLE_JOB_DETAILS = "JOB_DETAILS";String TABLE_TRIGGERS = "TRIGGERS";String TABLE_SIMPLE_TRIGGERS = "SIMPLE_TRIGGERS";String TABLE_CRON_TRIGGERS = "CRON_TRIGGERS";String TABLE_BLOB_TRIGGERS = "BLOB_TRIGGERS";String TABLE_FIRED_TRIGGERS = "FIRED_TRIGGERS";String TABLE_CALENDARS = "CALENDARS";String TABLE_PAUSED_TRIGGERS = "PAUSED_TRIGGER_GRPS";String TABLE_LOCKS = "LOCKS";String TABLE_SCHEDULER_STATE = "SCHEDULER_STATE";// TABLE_JOB_DETAILS columns namesString COL_SCHEDULER_NAME = "SCHED_NAME";String COL_JOB_NAME = "JOB_NAME";String COL_JOB_GROUP = "JOB_GROUP";String COL_IS_DURABLE = "IS_DURABLE";String COL_IS_VOLATILE = "IS_VOLATILE";String COL_IS_NONCONCURRENT = "IS_NONCONCURRENT";String COL_IS_UPDATE_DATA = "IS_UPDATE_DATA";String COL_REQUESTS_RECOVERY = "REQUESTS_RECOVERY";String COL_JOB_DATAMAP = "JOB_DATA";String COL_JOB_CLASS = "JOB_CLASS_NAME";String COL_DESCRIPTION = "DESCRIPTION";// TABLE_TRIGGERS columns namesString COL_TRIGGER_NAME = "TRIGGER_NAME";String COL_TRIGGER_GROUP = "TRIGGER_GROUP";String COL_NEXT_FIRE_TIME = "NEXT_FIRE_TIME";String COL_PREV_FIRE_TIME = "PREV_FIRE_TIME";String COL_TRIGGER_STATE = "TRIGGER_STATE";String COL_TRIGGER_TYPE = "TRIGGER_TYPE";String COL_START_TIME = "START_TIME";String COL_END_TIME = "END_TIME";String COL_PRIORITY = "PRIORITY";String COL_MISFIRE_INSTRUCTION = "MISFIRE_INSTR";String ALIAS_COL_NEXT_FIRE_TIME = "ALIAS_NXT_FR_TM";// TABLE_SIMPLE_TRIGGERS columns namesString COL_REPEAT_COUNT = "REPEAT_COUNT";String COL_REPEAT_INTERVAL = "REPEAT_INTERVAL";String COL_TIMES_TRIGGERED = "TIMES_TRIGGERED";// TABLE_CRON_TRIGGERS columns namesString COL_CRON_EXPRESSION = "CRON_EXPRESSION";// TABLE_BLOB_TRIGGERS columns namesString COL_BLOB = "BLOB_DATA";String COL_TIME_ZONE_ID = "TIME_ZONE_ID";// TABLE_FIRED_TRIGGERS columns namesString COL_INSTANCE_NAME = "INSTANCE_NAME";String COL_FIRED_TIME = "FIRED_TIME";String COL_SCHED_TIME = "SCHED_TIME";String COL_ENTRY_ID = "ENTRY_ID";String COL_ENTRY_STATE = "STATE";// TABLE_CALENDARS columns namesString COL_CALENDAR_NAME = "CALENDAR_NAME";String COL_CALENDAR = "CALENDAR";// TABLE_LOCKS columns namesString COL_LOCK_NAME = "LOCK_NAME";// TABLE_LOCKS columns namesString COL_LAST_CHECKIN_TIME = "LAST_CHECKIN_TIME";String COL_CHECKIN_INTERVAL = "CHECKIN_INTERVAL";// MISC CONSTANTSString DEFAULT_TABLE_PREFIX = "QRTZ_";// STATESString STATE_WAITING = "WAITING";String STATE_ACQUIRED = "ACQUIRED";String STATE_EXECUTING = "EXECUTING";String STATE_COMPLETE = "COMPLETE";String STATE_BLOCKED = "BLOCKED";String STATE_ERROR = "ERROR";String STATE_PAUSED = "PAUSED";String STATE_PAUSED_BLOCKED = "PAUSED_BLOCKED";String STATE_DELETED = "DELETED";/*** @deprecated Whether a trigger has misfired is no longer a state, but * rather now identified dynamically by whether the trigger's next fire * time is more than the misfire threshold time in the past.*/String STATE_MISFIRED = "MISFIRED";String ALL_GROUPS_PAUSED = "_$_ALL_GROUPS_PAUSED_$_";// TRIGGER TYPES/** Simple Trigger type. */String TTYPE_SIMPLE = "SIMPLE";/** Cron Trigger type. */String TTYPE_CRON = "CRON";/** Calendar Interval Trigger type. */String TTYPE_CAL_INT = "CAL_INT";/** Daily Time Interval Trigger type. */String TTYPE_DAILY_TIME_INT = "DAILY_I";/** A general blob Trigger type. */String TTYPE_BLOB = "BLOB";
}// EOF

里面有quartz的表名、各个表包含的列名、trigger状态、trigger类型等内容。更多springboot内容，可以在Java知音公众号回复“”springboot聚合。

状态包括

WAITING：等待中
ACQUIRED：将触发，此时还未到trigger真正的触发时刻
EXECUTING：触发，亦可理解成执行中，trigger真正的触发时刻
COMPLETE：完成，不再触发
BLOCKED：受阻，不允许并发执行job时会出现（@DisallowConcurrentExecution）
ERROR：出错
PAUSED：暂停中
PAUSED_BLOCKED：暂停受阻，不允许并发执行job时会出现（@DisallowConcurrentExecution）
DELETED：已删除
MISFIRED：触发失败，已弃用，有另外的替代方式

状态变化流程图如下所示

trigger的初始状态是WAITING，处于WAITING状态的trigger等待被触发。调度线程会不停地扫triggers表，根据NEXT_FIRE_TIME提前拉取即将触发的trigger，如果这个trigger被该调度线程拉取到，它的状态就会变为ACQUIRED。

因为是提前拉取trigger，并未到达trigger真正的触发时刻，所以调度线程会等到真正触发的时刻，再将trigger状态由ACQUIRED改为EXECUTING。如果这个trigger不再执行，就将状态改为COMPLETE,否则为WAITING，开始新的周期。如果这个周期中的任何环节抛出异常，trigger的状态会变成ERROR。如果手动暂停这个trigger，状态会变成PAUSED。

总结

Quartz作为一个开源的作业调度框架，提供了巨大的灵活性而不牺牲简单性。我们能够用它来为执行一个作业而创建简单的或复杂的调度。它有很多特征，如：数据库、集群、插件、JavaMail支持，EJB作业预构建，支持cron-like表达式等等；

springboot集成quartz非常简单，最简单的情况下只需要引入依赖我们就可以享受quartz提供的功能，springboot默认会帮我们配置好quartz；当然我们也可以自定义配置来实现quartz的定制；

参考

https://www.ibm.com/developerworks/cn/java/j-lo-taskschedule/index.html
https://gitee.com/52itstyle/spring-boot-quartz
https://docs.spring.io/spring-boot/docs/2.0.3.RELEASE/reference/htmlsingle/#boot-features-quartz
https://xuzongbao.gitbooks.io/quartz/content/
https://segmentfault.com/a/1190000015492260
http://www.quartz-scheduler.org/documentation/faq.html

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