package ejava.examples.jndidemo.dao;
   
   import java.util.List;
   
   
   import javax.enterprise.inject.Typed;
   import javax.inject.Inject;
   import javax.persistence.EntityManager;
   
  
  import ejava.examples.jndidemo.JndiDemo;
  import ejava.examples.jndidemo.bo.Task;
  
  /**
   * This class represents a single JPA DAO implementation for tasks.
   */
  @Typed({SchedulerDAO.class, JPASchedulerDAOImpl.class})
  public class JPASchedulerDAOImpl extends JPADAOBase<Task> implements SchedulerDAO {
  	
  	@Inject 
  	public void setEntityManager(@JndiDemo EntityManager em) {
  		super.em = em;
  	}
  	
  	public Task get(int id) {
  		return em.find(Task.class, id);
  	}
  
  	@Override
  	public Task findByName(String name) {
  		List<Task> tasks = 
  		em.createQuery("select t from Task t where t.name=:name", Task.class)
  			.setParameter("name", name)
  			.getResultList();
  		return tasks.size()==0 ? null : tasks.get(0);
  	}
  
  	@Override
  	public List<Task> getTasks(int offset, int limit) {
  		return em.createQuery("select t from Task t", Task.class)
  				.setFirstResult(offset)
  				.setMaxResults(limit)
  				.getResultList();
  	}
  
  	@Override
  	public String toString() {
  		return new StringBuilder(super.toString())
  			.append(", em=" + em).toString();
  	}
  }