Friday, September 01, 2006

Testing your Java Persistence API queries interactively

One of aspects of developing with ORMs is to test your JPA, EJB, Hibernate QL queries and get the results you wanted before hard coding it into your web application. For Hibernate, there's Hibernate tools but what about JPA? And within the Spring framework. Fortunately, the Spring framework provides a class (org.springframework.test.jpa.AbstractJpaTests;) to test your DAOs, which you can just adapt to make a sort of 'Query Tester'.

Here's what I did

public class JpaJobboardTests extends AbstractJpaTests {

  private JobDao jobDao;
  protected String[] getConfigLocations() {
    return new String[] {
    public void testQuery() {
        Query q = sharedEntityManager.createQuery(

                "SELECT DISTINCT j FROM Job j " +
                "JOIN i " +
                "JOIN j.employmentTypes e " +
                "JOIN j.qualification q " +
                "WHERE " +
                " BETWEEN 2 AND 4" +
                " AND " +
                " IN (4) " +
                " AND IN (3)"

        List jobs = q.getResultList();
        Iterator iterator = jobs.iterator();
        while (iterator.hasNext()) {
            Job job = (Job);
            System.out.println(job.getId() + " : " + job.getPosition());

    public void testGetAllJobs() {
        List jobs = this.jobDao.findAll();        
    public JobDao getJobDao() {
        return jobDao;
    public void setJobDao(JobDao jobDao) {
        this.jobDao = jobDao;

Plug it into my favorite IDE, and run it. You can edit your queries and see the results interactively.

Sure, you could code a seperate application just to do this, with named queries stored in a seperate XML file, and changing the queries in the external file, and not the source codes and recompiling every time.

No comments:

Post a Comment