package ejava.projects.edmv.jpa;
   
   import java.util.List;
   
   import javax.persistence.EntityManager;
   
   import ejava.projects.edmv.bo.Person;
   import ejava.projects.edmv.dao.PersonDAO;
   
  /**
   * This class provides a _sparse_ example of a JPA DAO for the class project.
   * It is put in place here to demonstrate some of the end-to-end use cases,
   *
   */
  public class JPAPersonDAO implements PersonDAO {
  	private EntityManager em;
  	
  	public void setEntityManager(EntityManager em) {
  		this.em = em;
  	}
  
  	public void createPerson(Person person) {
          em.persist(person);
  	}
  	
  	public Person getPerson(long id) {
  	    return em.find(Person.class, id);
  	}
  
  	@SuppressWarnings("unchecked")
      public List<Person> getPeople(int index, int count)  {
  	    return (List<Person>)em.createQuery("select p from Person p")
  	                             .setFirstResult(index)
  	                             .setMaxResults(count)
  	                             .getResultList();
  	}
  }