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Java Spring with Hibernate Data-Driven Application Design Add a DAO

Posted by David Prince
David Prince
5,799 Points

Can't pass the challenge. When I modify code from Treehouse's github it cannot find symbol for .getCriteriaBuilder.

I've spent a lot of time on this, looked at other's questions about it. Tried having it return null. I'm pretty lost.

com/teamtreehouse/contactmgr/dao/ContactDao.java 
package com.teamtreehouse.contactmgr.dao;

import com.teamtreehouse.contactmgr.model.Contact;

import java.util.List;

public interface ContactDao {
  List<Contact> findAll();

}
com/teamtreehouse/contactmgr/dao/ContactDaoImpl.java 
package com.teamtreehouse.contactmgr.dao;

import com.teamtreehouse.contactmgr.model.Contact;
import org.hibernate.Hibernate;
import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Repository;
import javax.persistence.criteria.CriteriaBuilder;
import javax.persistence.criteria.CriteriaQuery;
import java.util.List;

@Repository
public class ContactDaoImpl implements ContactDao {

    @Autowired
    private SessionFactory sessionFactory;

    @Override
    @SuppressWarnings("unchecked")
    public List<Contact> findAll() {
        // Open a session
        Session session = sessionFactory.openSession();

        // DEPRECATED as of Hibernate 5.2.0
       List<Contact> contactss = session.createCriteria(Contact.class).list();

        // Create CriteriaBuilder
        CriteriaBuilder builder = session.getCriteriaBuilder();

        // Create CriteriaQuery
       CriteriaQuery<Contact> criteria = builder.createQuery(Contact.class);

        // Specify criteria root
       criteria.from(Contact.class);

        // Execute query
        List<Contact> contacts = session.createQuery(criteria).getResultList();

        // Close session
        session.close();

        return contacts;
    }

}

1 Answer

Daniel Vargas
Daniel Vargas
29,184 Points
Daniel Vargas
Daniel Vargas
29,184 Points

Hi

I struggled with this challenge as well, it turns out to be a little simpler than you think

package com.teamtreehouse.contactmgr.dao;

import com.teamtreehouse.contactmgr.model.Contact;

import java.util.List;

public interface ContactDao {

  List<Contact> findAll();  
}

And in the ContactDaoImpl you just had to annotate the class and implement the method, but you didn't need to add a behavior:

package com.teamtreehouse.contactmgr.dao;

import com.teamtreehouse.contactmgr.model.Contact;
import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Repository;

import java.util.List;

@Repository
public class ContactDaoImpl implements ContactDao {

  @Override
  public List<Contact> findAll(){
   return null; 
  }

}