How to add queries by search criteria? - jhipster

Question

I am new to jhipster.
Is there a guide of steps to follow to implement search criteria?
I want to add to an entity, the possibility of filtering by any of its fields.
I have enabled filtering, but can't find a mode to show up on the entity's CRUD page.
I understand that I have to code in different places in the application ... but I did not find any examples or guides.
In advance, thank you very much for giving me some help

Answer 1

I don't know any guide for that but I also use Jhipster and developed my app search criteria and works fine. I hope this is what you're looking for.
I gonna use a comment table as an example where I want to filter by hidden, flagged, or both with the possibility of pagination on front. So I created a CommentRepositoryCustom.java:
import org.springframework.data.domain.Page;
import org.springframework.data.domain.Pageable;
public interface CommentRepositoryCustom {
Page<Comment> findCommentByCommentHiddenAndFlagged(Boolean hidden, Boolean flagged, Pageable pageable);
}
After that I created the implementation for my findCommentByCommentHiddenAndFlagged in another custom repository I created called CommentRepositoryCustomImpl.java:
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.data.domain.Page;
import org.springframework.data.domain.PageImpl;
import org.springframework.data.domain.Pageable;
import org.springframework.stereotype.Repository;
import org.springframework.transaction.annotation.Transactional;
import javax.persistence.EntityManager;
import javax.persistence.TypedQuery;
import javax.persistence.criteria.CriteriaBuilder;
import javax.persistence.criteria.CriteriaQuery;
import javax.persistence.criteria.Predicate;
import javax.persistence.criteria.Root;
#Repository
#Transactional
public class CommentRepositoryCustomImpl implements CommentRepositoryCustom{
private static final String HIDDEN_LABEL = "hidden";
private static final String FLAGGED_LABEL = "flagged";
#Autowired
private EntityManager em;
#Override
public Page<Comment> findCommentByCommentHiddenAndFlagged(Boolean hidden, Boolean flagged, Pageable pageable) {
CriteriaBuilder criteriaBuilder = em.getCriteriaBuilder();
CriteriaQuery<Comment> commentCriteriaQuery = criteriaBuilder.createQuery(Comment.class);
Root<Comment> commentRoot = commentCriteriaQuery.from(Comment.class);
Predicate predicateHidden = criteriaBuilder.equal(commentRoot.get(HIDDEN_LABEL), hidden);
Predicate predicateFlagged = criteriaBuilder.equal(commentRoot.get(FLAGGED_LABEL), flagged);
Predicate concatenate;
TypedQuery<Comment> typedQuery;
CriteriaQuery<Long> countQuery = criteriaBuilder.createQuery(Long.class);
Root<Comment> countCommentRoot = countQuery.from(Comment.class);
Long count;
if (hidden != null && flagged != null) {
concatenate = criteriaBuilder.and(predicateHidden);
concatenate = criteriaBuilder.and(concatenate, predicateFlagged);
countQuery.select(criteriaBuilder.count(countCommentRoot)).where(concatenate);
typedQuery = em.createQuery(commentCriteriaQuery.select(commentRoot).where(concatenate));
} else if(hidden != null) {
concatenate = criteriaBuilder.and(predicateHidden);
countQuery.select(criteriaBuilder.count(countCommentRoot)).where(concatenate);
typedQuery = em.createQuery(commentCriteriaQuery.select(commentRoot).where(concatenate));
} else if (flagged != null) {
concatenate = criteriaBuilder.and(predicateFlagged);
countQuery.select(criteriaBuilder.count(countCommentRoot)).where(concatenate);
typedQuery = em.createQuery(commentCriteriaQuery.select(commentRoot).where(concatenate));
} else {
countQuery.select(criteriaBuilder.count(countCommentRoot));
typedQuery = em.createQuery(commentCriteriaQuery.select(commentRoot));
}
typedQuery.setFirstResult((int) pageable.getOffset()).setMaxResults(pageable.getPageSize());
count = em.createQuery(countQuery).getSingleResult();
return new PageImpl<>(typedQuery.getResultList(), pageable, count);
}
}
Now you just need to call findCommentByCommentHiddenAndFlagged with the right params in your service.
Let me know if this what you're looking for.

Answer 2

Do you have a Get endpoint in package web.rest that looks like this? #GetMapping("/clcomments") public ResponseEntity<List<Entity>> getAllComments(CommentsCriteria criteria) {... }
If you do, search by criteria works!