JBatch fails to execute job on @Startup

[tosuns]

Hi,

During my testing with jbatch I observed that the batch runtime fails to execute the job if the job gets started via @PostConstruct of a singleton ejb with @Startup-Annotation.
The jobs runs fine, but (in my case) the actual batchlet gets not executed.

I think/guess the probleme is related to the following issue, which I posted last year on the glassfish issue tracker: https://java.net/jira/browse/GLASSFISH-21216

To reproduce:

1). create a simple web-app
2). create a singleton ejb:

@Singleton
@Startup
public class JobStarter {
    private static final Logger LOG = Logger.getLogger(JobStarter.class.getName());
    @PostConstruct
    protected void start() {
        LOG.log(Level.INFO,
                "simple-job with id {0} started...",
                BatchRuntime.getJobOperator().start("simple-job", null));
    }
}

3). create a simple Batchlet implementation:

@Named
public class Batchlet extends AbstractBatchlet {
    private static final Logger LOG = Logger.getLogger(Batchlet.class.getName());
    @Inject
    private JobContext jobContext;
    @Inject
    private StepContext stepContext;
    @Override
    public String process() throws Exception {
        LOG.log(Level.INFO, "Batchlet {0} of job {1} finished!",
                new Object[]{
                    stepContext.getStepName(),
                    jobContext.getJobName()
                });

        return BatchStatus.COMPLETED.name();
    }
}

4). and the simple-job.xml file:

<?xml version="1.0" encoding="UTF-8"?>
<job xmlns="http://xmlns.jcp.org/xml/ns/javaee" 
     xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
     xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee http://xmlns.jcp.org/xml/ns/javaee/jobXML_1_0.xsd"
     version="1.0"
     id="simple-job">           
    <step id="step-one"> 
        <batchlet ref="batchlet"/>       
    </step>   
</job>

On the console you will see the output of the ejb but not the output of the batchlet.

But if you use a @schedule annotation instead of @PostConstruct, the batchlet output gets printed.

[smillidge]

This has been reproduced.

This is caused by the Batch job executor service checking that the application is enabled before executing the Batch task. However as the application is still deploying this check fails and the batch task is not started.

The race condition arises because the Session bean @PostConstruct is called before the application is fully deployed.

[smillidge]

This is fixable but I'm not sure if it would work in all cases as the application may not be fully deployed before the batch job is executed.

[smillidge]

The EJB specification doesn't state that you can use JBatch or concurrency utility within a Singleton @startup @PostConstruct method. I suppose this needs clarification from EJB spec leads. I will try to raise with them.

The spec says you can only do;

SessionContext methods: getBusinessObject, getRollbackOnly, setRollbackOnly, getTimerService, lookup, getContextData
JNDI access to java:comp/env
Resource manager access
Enterprise bean access
EntityManagerFactory access
EntityManager access
TimerService and Timer methods

[smillidge]

Requires input from EJB spec leads

[AdamBien]

According to the spec 3.2:
"
4.3.14 Transaction Context of Session Bean Methods
The following session bean methods are invoked in the scope of a transaction determined by the trans- action attribute specified in the bean’s metadata annotations or deployment descriptor.
(...)
• A singleton session bean’s PostConstruct or PreDestroy lifecycle callback interceptor method."

In PostConstruct all injected components should be already initialized and "ready to use".

Try to run the PostConstruct method within a transaction. Beginning with Java EE 7 it is allowed to execute lifecycle methods within a transaction.

[smillidge]

Related GlassFish JIRA https://java.net/jira/browse/GLASSFISH-21087 for concurrent tasks