CODEWITHSUNDEEP
hibernatejpql
Dani
Dani

Reputation: 4111

QuerySyntaxException locating appropriate constructor in Hibernate

When I try to do the next one HQL query i get next error:

org.hibernate.hql.internal.ast.QuerySyntaxException: Unable to locate appropriate constructor on class [package.CountItemLike] [SELECT NEW package.CountItemLike(ll.itemId, COUNT(ll.itemId)) FROM package.ItemLike AS ll GROUP BY ll.itemId]

In my DAO class

@Override
public List<CountItemLike> countItemLikes() {

    String hql = "SELECT NEW package.CountItemLike"
            + "(ll.itemId, COUNT(ll.itemId)) "
            + "FROM ItemLike AS ll "
            + "GROUP BY ll.itemId";

    Query query = this.getCurrentSession().createQuery(hql); // ERROR IS HERE

    return (List<CountItemLike>) query.list();
}

POJO

public class CountItemLike {

    private int itemId;
    private int likes;

    public CountItemLike(int itemId, int likes){

        this.itemId = itemId;
        this.likes = likes;        
    }

    public int getItemId() {
        return itemId;
    }

        public int getLikes() {
        return likes;
    }   

}

Upvotes: 3

Views: 6369

Answers (1)

Mikko Maunu
Mikko Maunu

Reputation: 42084

Returned value is Long when aggregate function count is used. That's why applicable constructors are:

  public CountItemLike(int itemId, Long likes){
        this.itemId = itemId;
        this.likes = likes.intValue();        
  }

or:

  public CountItemLike(int itemId, long likes){
        this.itemId = itemId;
        this.likes = (int) likes;        
  }

Maybe there is additionally type mismatch between ItemLike.itemId and int, but that cannot be seen from the given code.

Upvotes: 7

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