UserSessionBean.java

package com.todo.ejb;

import javax.ejb.Stateless;
import javax.persistence.EntityManager;
import javax.persistence.PersistenceContext;
import javax.persistence.Query;
import com.todo.entity.User;

@Stateless
public class UserSessionBean implements UserSessionBeanLocal {

	@PersistenceContext(unitName = "TodoJPA")
	private EntityManager entityManager;

	@Override
	public User findUser(String username, String password) {

		User user;
		try {
			Query query = entityManager.createQuery("SELECT u FROM User as u WHERE u.username=?1 and u.password=?2");

			query.setParameter(1, username);

			query.setParameter(2, password);

			user = (User) query.getSingleResult();
			
			return user;
			
		} catch (Exception e) {
			e.printStackTrace();
			return null;
		}

	}

}