使用Hibernate sessionFactory工具类来对数据的增删改查

package com.ask.test;
import java.util.Date;
import java.util.List;
import org.hibernate.Criteria;
import org.hibernate.Query;
import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.hibernate.Transaction;
import org.junit.Before;
import org.junit.Test;
import com.ask.pojo.Emp;
import com.ask.util.HibernateUtil;
public class EmpTest {

private SessionFactory sessionFactory;
@Before
public void setUp() throws Exception {
//使用hibernateUtil工具类来创建单例的sessionFactory 对象
//再使用sessionFactory 对象来创建session
//工具类提供一个创建session的方法
sessionFactory=HibernateUtil.getSessionFactory();
}
//根据用户id查询;
@Test
public void testSelectById() {
Session session=sessionFactory.openSession();
// 根据id查询emp数据
Emp e = (Emp) session.get(Emp.class, 1);
System.out.println(e);
}
//增加;
@Test
public void testInsert(){
Session session=sessionFactory.openSession();
Transaction tx=session.beginTransaction();
Emp e=new Emp("lucy","1",new Date());
session.save(e);
tx.commit();
session.close();
//sessionFactory.close();

}
//删除;
@Test
public void testDelete(){
Session session=sessionFactory.openSession();
Transaction tx=session.beginTransaction();
Emp e=(Emp) session.get(Emp.class,3);
session.delete(e);
tx.commit();
session.close();
}

//根据id唯一进行查询;
@Test
public void testSelectUnique() {
Session session=sessionFactory.openSession();
String hql="From Emp e where e.id=:id";
Query query = session.createQuery(hql);
query.setInteger("id",3);
Emp e =(Emp) query.uniqueResult();
System.out.println(e);
session.close();

}
//查询分页;
@Test
public void testSelectList() {
Session session=sessionFactory.openSession();
String hql="From Emp";
Query query = session.createQuery(hql);
List<Emp> e=query.list();
for (Emp emp : e) {
System.out.println(emp);
}
session.close();
}

//criteria分页查询;
@Test
public void testSelectQBCList() {
Session session = sessionFactory.openSession();
Criteria criteria= session.createCriteria(Emp.class);
criteria.setFirstResult(0);
criteria.setMaxResults(3);
List<Emp> e=criteria.list();
for (Emp emp : e) {
System.out.println(emp);
}
session.close();
}

}