Firebird Job Queue and Task Orchestration with Spring Boot

February 08, 2026

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After setting up asynchronous processing, the next step toward a scalable data workflow is job queuing and orchestration. With a queue, you can manage execution order, retries, and dependencies between tasks — ensuring Firebird operations run smoothly without overloading your system.

1. Why Use a Job Queue

In large-scale systems, you might have many background tasks — data imports, cleanups, reports, backups — all competing for resources.
Without control, multiple tasks can run at once, causing connection exhaustion or data contention. A job queue solves this by:

• Controlling concurrency and order of execution.
• Automatically retrying failed tasks.
• Tracking job states (pending, running, completed, failed).
• Enabling recovery after restarts.

2. Designing a Simple Job Entity

You can represent each queued task as a database record in Firebird.

@Entity
public class JobQueue {
    @Id
    @GeneratedValue
    private Long id;
    private String jobName;
    private String status; // PENDING, RUNNING, COMPLETED, FAILED
    private LocalDateTime createdAt;
    private LocalDateTime startedAt;
    private LocalDateTime completedAt;
    private String errorMessage;
}

This entity will store job details and status throughout the lifecycle.

3. Creating a Job Queue Repository

Use a standard JPA repository for database operations:

public interface JobQueueRepository extends JpaRepository<JobQueue, Long> {
    List<JobQueue> findTop5ByStatusOrderByCreatedAtAsc(String status);
}

This method fetches a limited number of pending jobs for processing.

4. Implementing the Job Processor

A service can continuously scan the queue and execute pending jobs asynchronously:

@Service
public class JobProcessorService {

    @Autowired
    private JobQueueRepository jobRepo;

    @Async("firebirdExecutor")
    public void processPendingJobs() {
        List<JobQueue> pendingJobs = jobRepo.findTop5ByStatusOrderByCreatedAtAsc("PENDING");

        for (JobQueue job : pendingJobs) {
            job.setStatus("RUNNING");
            job.setStartedAt(LocalDateTime.now());
            jobRepo.save(job);

            try {
                executeJob(job);
                job.setStatus("COMPLETED");
            } catch (Exception e) {
                job.setStatus("FAILED");
                job.setErrorMessage(e.getMessage());
            }

            job.setCompletedAt(LocalDateTime.now());
            jobRepo.save(job);
        }
    }

    private void executeJob(JobQueue job) {
        System.out.println("Running job: " + job.getJobName());
        // Add Firebird logic here (cleanup, backup, report, etc.)
    }
}

Each job runs in a background thread, isolated from the main thread.

5. Scheduling Job Queue Scans

Use a scheduled task to check the queue periodically and dispatch jobs automatically:

@Component
public class JobScheduler {

    @Autowired
    private JobProcessorService processor;

    @Scheduled(fixedDelay = 10000)
    public void scheduleQueueProcessing() {
        processor.processPendingJobs();
    }
}

This checks every 10 seconds for new jobs and processes them as soon as they arrive.

6. Adding Retry Logic

Automatic retries help recover from transient issues like temporary connection failures.
Add a retry counter and logic inside JobProcessorService:

if ("FAILED".equals(job.getStatus()) && job.getRetryCount() < 3) {
    job.setStatus("PENDING");
    job.setRetryCount(job.getRetryCount() + 1);
    jobRepo.save(job);
}

This ensures each job gets retried up to three times before being permanently marked as failed.

7. Exposing Job Status via REST API

Allow users to view the job queue and status updates through an API endpoint:

@RestController
@RequestMapping("/api/jobs")
public class JobController {

    @Autowired
    private JobQueueRepository jobRepo;

    @GetMapping
    public List<JobQueue> listJobs() {
        return jobRepo.findAll(Sort.by(Sort.Direction.DESC, "createdAt"));
    }

    @PostMapping
    public String createJob(@RequestBody JobQueue job) {
        job.setStatus("PENDING");
        job.setCreatedAt(LocalDateTime.now());
        jobRepo.save(job);
        return "Job added to queue: " + job.getJobName();
    }
}

Users can trigger new tasks and monitor job history directly from the dashboard.