DAO for Student

StudentDAO.java

package ajfmo.studycontrol.DAO;

import java.util.List;

import javax.persistence.criteria.CriteriaBuilder;
import javax.persistence.criteria.CriteriaQuery;
import javax.persistence.criteria.Root;

import org.hibernate.HibernateException;
import org.hibernate.Session;
import org.hibernate.Transaction;

import ajfmo.studycontrol.entities.Career;
import ajfmo.studycontrol.entities.Section;
import ajfmo.studycontrol.entities.Student;
import ajfmo.studycontrol.utils.HibernateUtil;

public class StudentDAO {

	private final Session session = HibernateUtil.getSessionFactory();
	private Transaction transaction = null;
	private CriteriaBuilder builder = session.getCriteriaBuilder();

	private Student student;

	public void createStudent(String studentId, String studentName, Career career, Section section) {
		student = new Student(studentId, studentName, career, section);
		try {
			transaction = session.beginTransaction();
			System.out.println(studentId);
			System.out.println(studentName);
			System.out.println(career);
			System.out.println(section);
			session.save(student);
			transaction.commit();
		} catch (HibernateException e) {
			e.printStackTrace();
		}
		session.close();
	}

	public List<Student> studentCriteria() {
		CriteriaQuery<Student> criteria = builder.createQuery(Student.class);
		Root<Student> root = criteria.from(Student.class);
		criteria.select(root);
		List<Student> resultset = session.createQuery(criteria).getResultList();
		return resultset;
	}

	public List<Career> careerCriteria() {
		CriteriaQuery<Career> criteria = builder.createQuery(Career.class);
		Root<Career> root = criteria.from(Career.class);
		criteria.select(root);
		List<Career> resultset = session.createQuery(criteria).getResultList();
		return resultset;
	}

	public List<Section> sectionCriteria() {
		CriteriaQuery<Section> criteria = builder.createQuery(Section.class);
		Root<Section> root = criteria.from(Section.class);
		criteria.select(root);
		List<Section> resultset = session.createQuery(criteria).getResultList();
		return resultset;
	}
}