Java实现quartz任务失败后怎么实现自动重试

在Quartz中，可以通过实现Job接口的execute方法来定义需要执行的任务。如果任务执行失败，可以通过实现JobListener接口并在jobWasExecuted方法中检查执行结果，并在需要时重新触发任务来实现自动重试。下面是一种实现方式：

1. 实现Job接口并定义任务逻辑。

public class MyJob implements Job {
    @Override
    public void execute(JobExecutionContext context) throws JobExecutionException {
        // 执行任务逻辑，如果任务失败，则抛出JobExecutionException异常
        boolean success = doJob();
        if (!success) {
            throw new JobExecutionException("任务执行失败");
        }
    }

    private boolean doJob() {
        // 执行任务逻辑，返回任务是否成功的结果
    }
}

2. 实现JobListener接口并在jobWasExecuted方法中检查任务执行结果。如果任务执行失败，并且重试次数未达到最大次数，则重新触发任务。

public class MyJobListener implements JobListener {

    private static final int MAX_RETRY_TIMES = 3; // 最大重试次数

    @Override
    public String getName() {
        return "MyJobListener";
    }

    @Override
    public void jobToBeExecuted(JobExecutionContext context) {
        // do nothing
    }

    @Override
    public void jobExecutionVetoed(JobExecutionContext context) {
        // do nothing
    }

    @Override
    public void jobWasExecuted(JobExecutionContext context, JobExecutionException exception) {
        if (exception != null) {
            JobDetail jobDetail = context.getJobDetail();
            JobDataMap jobDataMap = jobDetail.getJobDataMap();
            int retryTimes = jobDataMap.getInt("retryTimes");
            if (retryTimes < MAX_RETRY_TIMES) {
                retryTimes++;
                jobDataMap.put("retryTimes", retryTimes);
                JobBuilder jobBuilder = JobBuilder.newJob(MyJob.class);
                jobBuilder.withIdentity(jobDetail.getKey().getName(), jobDetail.getKey().getGroup());
                jobBuilder.usingJobData(jobDataMap);
                JobDetail newJobDetail = jobBuilder.build();
                Trigger trigger = context.getTrigger();
                Trigger newTrigger = TriggerBuilder.newTrigger()
                        .withIdentity(trigger.getKey().getName(), trigger.getKey().getGroup())
                        .startNow()
                        .build();
                try {
                    context.getScheduler().scheduleJob(newJobDetail, newTrigger);
                } catch (SchedulerException e) {
                    e.printStackTrace();
                }
            }
        }
    }
}

3. 在任务调度器中添加JobListener。可以通过SchedulerFactory和Scheduler来创建和配置任务调度器，并添加JobListener。

public class MyScheduler {

    public static void main(String[] args) throws SchedulerException {
        SchedulerFactory schedulerFactory = new StdSchedulerFactory();
        Scheduler scheduler = schedulerFactory.getScheduler();
        JobBuilder jobBuilder = JobBuilder.newJob(MyJob.class);
        jobBuilder.withIdentity("MyJob", "MyGroup");
        JobDataMap jobDataMap = new JobDataMap();
        jobDataMap.put("retryTimes", 0);
        jobBuilder.usingJobData(jobDataMap);
        JobDetail jobDetail = jobBuilder.build();
        Trigger trigger = TriggerBuilder.newTrigger()
                .withIdentity("MyTrigger", "MyGroup")
                .startNow()
                .build();
        MyJobListener jobListener = new MyJobListener();
        scheduler.getListenerManager().addJobListener(jobListener);
      }
}