JAVA高级面试进阶训练营视频教程

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我们要达到这样的效果

public class CancelUnpaidOrderTask implements Job { @Autowired private AppOrderService orderService; @Override public void execute(JobExecutionContext ctx) throws JobExecutionException { ... }

但是Job对象的实例化过程是在Quartz中进行的，AppOrderService是在Spring容器当中的，那么如何将他们关联到一起呢。好在Quartz提供了JobFactory接口，让我们可以自定义实现创建Job的逻辑。

public interface JobFactory {
 Job newJob(TriggerFiredBundle bundle, Scheduler scheduler) throws SchedulerException;
 }

那么我们通过实现JobFactory 接口，在实例化Job以后，在通过ApplicationContext 将Job所需要的属性注入即可

在Spring与Quartz集成时 用到的是org.springframework.scheduling.quartz.SchedulerFactoryBean这个类。源码如下，我们只看最关键的地方。

        // Get Scheduler instance from SchedulerFactory. try { this.scheduler = createScheduler(schedulerFactory, this.schedulerName); populateSchedulerContext(); if (!this.jobFactorySet && !(this.scheduler instanceof RemoteScheduler)) { // Use AdaptableJobFactory as default for a local Scheduler, unless when // explicitly given a null value through the "jobFactory" bean property. this.jobFactory = new AdaptableJobFactory(); } if (this.jobFactory != null) { if (this.jobFactory instanceof SchedulerContextAware) { ((SchedulerContextAware) this.jobFactory).setSchedulerContext(this.scheduler.getContext()); } this.scheduler.setJobFactory(this.jobFactory); } }

其中红色标记的是重点，如果我们不指定jobFactory，那么Spring就使用AdaptableJobFactory。我们在来看一下这个类的实现

package org.springframework.scheduling.quartz; import java.lang.reflect.Method; import org.quartz.Job; import org.quartz.Scheduler; import org.quartz.SchedulerException; import org.quartz.spi.JobFactory; import org.quartz.spi.TriggerFiredBundle; import org.springframework.util.ReflectionUtils; public class AdaptableJobFactory implements JobFactory { public Job newJob(TriggerFiredBundle bundle, Scheduler scheduler) throws SchedulerException { return newJob(bundle); } public Job newJob(TriggerFiredBundle bundle) throws SchedulerException { try { Object jobObject = createJobInstance(bundle); return adaptJob(jobObject); } catch (Exception ex) { throw new SchedulerException("Job instantiation failed", ex); } } protected Object createJobInstance(TriggerFiredBundle bundle) throws Exception { // Reflectively adapting to differences between Quartz 1.x and Quartz 2.0... Method getJobDetail = bundle.getClass().getMethod("getJobDetail"); Object jobDetail = ReflectionUtils.invokeMethod(getJobDetail, bundle); Method getJobClass = jobDetail.getClass().getMethod("getJobClass"); Class jobClass = (Class) ReflectionUtils.invokeMethod(getJobClass, jobDetail); return jobClass.newInstance(); } protected Job adaptJob(Object jobObject) throws Exception { if (jobObject instanceof Job) { return (Job) jobObject; } else if (jobObject instanceof Runnable) { return new DelegatingJob((Runnable) jobObject); } else { throw new IllegalArgumentException("Unable to execute job class [" + jobObject.getClass().getName() + "]: only [org.quartz.Job] and [java.lang.Runnable] supported."); } } }

其他的我们都不管，我们就看红色的地方，这里是创建了一个Job,那我们就在这里去给Job的属性进行注入就可以了，让我们写一个类继承它，然后复写这个方法进行对Job的注入。

按 Ctrl+C 复制代码

按 Ctrl+C 复制代码

接下来把他配置到Spring当中去

<bean id="jobFactory" class="com.gary.operation.jobdemo.demo1.MyJobFactory"></bean>

然后在把org.springframework.scheduling.quartz.SchedulerFactoryBean的jobFactory设置成我们自己的。

<bean name="MyScheduler" class="org.springframework.scheduling.quartz.SchedulerFactoryBean">
　　<!-- 其他属性省略 --> 　　<property name="jobFactory" ref="jobFactory"></property> </bean>

这样就完成了Spring对Job的注入功能，其实很简单，原理就是在我们扩展JobFactory创建job的方法，在创建完Job以后进行属性注入。