开发日志:Spring整合Quartz实现动态定时任务

Spring自带的定时任务只能在项目初始化时创建定时任务，通过ScheduledAnnotationBeanPostProcessor类处理@Scheduled注解并注册定时任务，无法灵活手动创建定时任务，接下来附上Quartz创建定时任务的用法。

1. 引入依赖

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

2. 编写测试类

package com.xxx.xxx;

import org.junit.Test;
import org.junit.runner.RunWith;
import org.quartz.*;
import org.springframework.boot.test.context.SpringBootTest;
import org.springframework.scheduling.quartz.SchedulerFactoryBean;
import org.springframework.test.context.ActiveProfiles;
import org.springframework.test.context.junit4.SpringRunner;

import javax.annotation.Resource;
import java.time.LocalDate;
import java.time.LocalDateTime;
import java.util.concurrent.ThreadLocalRandom;
import java.util.concurrent.TimeUnit;

@RunWith(SpringRunner.class)
@SpringBootTest
public class ApplicationTest {

    @Resource
    private SchedulerFactoryBean schedulerFactoryBean;

    @Test
    public void test(){
        try {
            TimeUnit.SECONDS.sleep(30);
        } catch (InterruptedException e) {
            e.printStackTrace();
        }
        Scheduler scheduler = schedulerFactoryBean.getScheduler();
        try {
            scheduler.scheduleJob(JobBuilder.newJob(((Job) jobExecutionContext -> System.out.println(LocalDateTime.now())).getClass())
                            .withIdentity("job1")
                            .build(),
                    TriggerBuilder.newTrigger().withIdentity("trigger1")
                            .withSchedule(SimpleScheduleBuilder.simpleSchedule()
                                    .withIntervalInSeconds(2).repeatForever()).build());
        } catch (SchedulerException e) {
            e.printStackTrace();
        }
        try {
            TimeUnit.MINUTES.sleep(10);
        } catch (InterruptedException e) {
            e.printStackTrace();
        }
    }
}

其中，schedulerFactoryBean持有Scheduler,scheduler.scheduleJob()方法需要传入需要执行的任务以及定时任务触发器，任务实现 org.quartz.Job接口。

3. 注意事项

当任务的id相同即withIdentity()传入的参数重复时，会出现异常：org.quartz.ObjectAlreadyExistsException: Unable to store Job : 'DEFAULT.job1', because one already exists with this identification.

以上是Quartz最简单的使用方式，更多内容待深究。