Define job registration mechanism with Java-defined job (e.g. at app startup?) about batch HOT 3 OPEN

void defineBatches(@Observes JobRegistrationCallback cb, JobOperator op, MyService service) {
    cb.defineJob("my-job")
       .batchlet("exec-sql", () -> service.executeBulkQuery().then(service::flush));
}

@Inject JobOperator op;
@Inject MyService service;

op.defineJob( (JobRegistrationCallback cb) -> {
    cb.defineJob("my-job")
       .batchlet("exec-sql", () -> service.executeBulkQuery().then(service::flush));
});

JobDefinition jobdef = op.defineJob( (JobRegistrationCallback cb) -> {
    return cb.defineJob("my-job");  
   // the `return` statement here isn't even necessary,
   // the `defineJob` method would get the definition from `cb` and return it
});
op.start( jobdef, new Properties() );

void defineBatches(@Observes @Initialized(ApplicationScoped.class) Object startup, JobRegistrationCallback cb /* optionally other services */) {
    cb.defineJob("my-job")
       .batchlet("exec-sql", () -> service.executeBulkQuery().then(service::flush));
}

@Inject JobRegistrationCallback cb;
@Inject MyService service;

cb.defineJob("my-job")
       .batchlet("exec-sql", () -> service.executeBulkQuery().then(service::flush));