Java EE 7 added the capability to perform Batch jobs in a standard way using JSR 352.

This code fragment is the Job Specification Language defined as XML, a.k.a. Job XML. It defines a canonical job, with a single step, using item-oriented or chunk-oriented processing. A chunk can have a reader, optional processor, and a writer. Each of these elements are identified using the corresponding elements in the Job XML, and are CDI beans packaged in the archive.

This job can be easily started using:

A typical question asked in different forums and conferences is how to schedule these jobs in a Java EE runtime. Batch 1.0 API itself does not offer anything to be schedule these jobs. However Java EE platform offers three different ways to schedule these jobs:

1. Use the @javax.ejb.Schedule annotation in an EJB.
   Here is a sample code that will trigger the execution of batch job at 11:59:59 PM every day.
   
   @Singleton public class MyEJB { @Schedule(hour = "23", minute = "59", second = "59") public void myJob() { BatchRuntime.getJobOperator().start("myJob", new Properties()); } }

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   @Singleton public class MyEJB {   @Schedule(hour = "23", minute = "59", second = "59")   public void myJob() {     BatchRuntime.getJobOperator().start("myJob", new Properties());   } }

   Of course, you can change the parameters of @Schedule to start the batch job at the desired time.
2. Use ManagedScheduledExecutorService using javax.enterprise.concurrent.Trigger as shown:
   
   @Stateless public class MyStatelessEJB { @Resource ManagedScheduledExecutorService executor; public void runJob() { executor.schedule(new MyJob(), new Trigger() { public Date getNextRunTime(LastExecution lastExecutionInfo, Date taskScheduledTime) { Calendar cal = Calendar.getInstance(); cal.setTime(taskScheduledTime); cal.add(Calendar.DATE, 1); return cal.getTime(); } public boolean skipRun(LastExecution lastExecutionInfo, Date scheduledRunTime) { return null == lastExecutionInfo; } }); } public void cancelJob() { executor.shutdown(); } }

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   @Stateless public class MyStatelessEJB {     @Resource     ManagedScheduledExecutorService executor;       public void runJob() {         executor.schedule(new MyJob(), new Trigger() {               public Date getNextRunTime(LastExecution lastExecutionInfo, Date taskScheduledTime) {                 Calendar cal = Calendar.getInstance();                 cal.setTime(taskScheduledTime);                 cal.add(Calendar.DATE, 1);                 return cal.getTime();             }               public boolean skipRun(LastExecution lastExecutionInfo, Date scheduledRunTime) {                 return null == lastExecutionInfo;             }           });     }       public void cancelJob() {         executor.shutdown();     } }

   Call runJob to initiate job execution and cancelJob to terminate job execution. In this case, a new job is started a day later than the previous task. And its not started until previous one is terminated. You will need more error checks for proper execution.

   MyJob is very trivial:

   public class MyJob implements Runnable { public void run() { BatchRuntime.getJobOperator().start("myJob", new Properties()); } }

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   public class MyJob implements Runnable {       public void run() {         BatchRuntime.getJobOperator().start("myJob", new Properties());     }   }

   Of course, you can automatically schedule it by calling this code in @PostConstruct.

3. A slight variation of second technique allows to run the job after a fixed delay as shown:
   public void runJob2() { executor.scheduleWithFixedDelay(new MyJob(), 2, 3, TimeUnit.HOURS); }

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   public void runJob2() {     executor.scheduleWithFixedDelay(new MyJob(), 2, 3, TimeUnit.HOURS); }

   The first task is executed 2 hours after the runJob2 method is called. And then with a 3 hours delay between subsequent execution.

This support is available to you within the Java EE platform. In addition, you can also invoke BatchRuntime.getJobOperator().start("myJob", new Properties()); from any of your Quartz-scheduled methods as well.

You can try all of this on WildFly.

And there are a ton of Java EE 7 samples at github.com/javaee-samples/javaee7-samples.

This particular sample is available at github.com/javaee-samples/javaee7-samples/tree/master/batch/scheduling.

How are you scheduling your Batch jobs ?

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