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javajpaormpaginationcriteria

How to paginate a JPA Query


I have a submission table with columns like ID, Name, Code among other properties. My requirement is to search for records based on the mentioned properties and return a paginated set.

This is the pseudocode for what I am looking for:

searchSubmission(searchFilter sf,pageIndex,noOfRecords) {
   query = 'from submisssion where code=sf.code or id=sf.id order by id start_from (pageIndex*noOfRecords) limit noOfRecords'
   return result();
}

There seem to be many options like CriteriaBuilder, NamedQuery, etc. Which is the most efficient one in this situation?


Solution

  • For all JPA query objects (except for native SQL queries), you would use pagination through the setMaxResults(int) and setFirstResult(int) methods. For instance:

      return em.createNamedQuery("yourqueryname", YourEntity.class)
          .setMaxResults(noOfRecords)
          .setFirstResult(pageIndex * noOfRecords)
          .getResultList();
    

    JPA will perform the pagination for you.

    Named queries are just predefined and can be cached, while other types are dynamically created.
    So the choice is to use JPQL like:

    Query query = em.createQuery("SELECT s FROM Submission s WHERE s.code = :code or s.id = :id ORDER BY s.id", Submission.class);
    

    Or CriteriaBuilder api to form a similar query:

        CriteriaBuilder qb = em.getCriteriaBuilder();
        CriteriaQuery<Submission> cq = qb.createQuery(Submission.class);
    
        Root<Submission> root = cq.from(Submission.class);
        cq.where( qb.or( 
            qb.equal(root.get("code"), qb.parameter(String.class, "code")),
            qb.equal(root.get("id"), qb.parameter(Integer.class, "id"))
        ));
        Query query = em.createQuery(cq);
    

    Don't forget to set the parameter values using query.setParameter("id", sf.id) for example.