Hibernate HQL查询 分页查询 模糊查询

/** * HQL查询的一个例子 */ public static void hql() { Session s = null; try { s = HibernateUtil.getSeesion(); //final String hql = "from User as u where u.name=?"; final String hql = "from User as u where u.name=:name"; final Query query = s.createQuery(hql); //query.setString(0, "北京市"); //从0开始 query.setString("name", "北京市"); final List<User> list = query.list(); for (final User u : list) { System.out.println(u.getName()); } } finally { if (s != null) { s.close(); } } System.out.println("HQL完成"); }

 

HibernateUtil工具类

package dao; import org.hibernate.Session; import org.hibernate.SessionFactory; import org.hibernate.cfg.Configuration; /** * 这是一个工具类, 快速取得session * */ public class HibernateUtil { static SessionFactory sessionFactory = null; static { final Configuration cfg = new Configuration(); cfg.configure(); //路径可以改变 sessionFactory = cfg.buildSessionFactory(); } public static SessionFactory getSessionFactory() { return sessionFactory; } /** * 取得session * * @return session */ public static Session getSeesion() { return sessionFactory.openSession(); } }

 

/** * HQL 分页查询 */ public static void page() { Session s = null; try { s = HibernateUtil.getSeesion(); final String hql = " from User "; //User是类名 final Query q = s.createQuery(hql); q.setFirstResult(0); //从第0条开始 q.setMaxResults(10); //取出10条 final List list = q.list(); for (final User u : list) { System.out.println(u.getId() + " " + u.getName()); } } finally { s.clear(); } }

 

模糊查询

public List<User> getUsers(String id){ List list=new ArrayList<User>(); String hql="from User as user where user.id like :id"; //参数名称查询 factory=DBHelper.getSessionFactory(); Session session=factory.openSession(); Transaction transaction=session.beginTransaction(); Query query=session.createQuery(hql); query.setString("id", "%"+id+"%"); list=query.list(); transaction.commit(); session.close(); return list; }

 

//可以拼字符串 List students = session.createQuery("select s.id, s.name from Student s where s.name like '%1%'").list(); //Query query = session.createQuery("select s.id, s.name from Student s where s.name like ?"); //query.setParameter(0, "%1%"); //List students = query.list(); //可以使用？方式传递参数 //参数的索引从0开始 //传递的参数值，不用单引号引起来 //注意方法链编程 List students = session.createQuery("select s.id, s.name from Student s where s.name like ?") .setParameter(0, "%1%") .list(); //使用 ：参数名称 的方式传递参数值 List students = session.createQuery("select s.id, s.name from Student s where s.name like :myname") .setParameter("myname", "%1%") .list(); //使用 ：参数名称 的方式传递参数值 List students = session.createQuery("select s.id, s.name from Student s where s.name like :myname and s.id=:myid") .setParameter("myname", "%1%") .setParameter("myid", 12) .list(); //支持in，需要使用setParameterList进行参数传递 List students = session.createQuery("select s.id, s.name from Student s where s.id in(:myids)") .setParameterList("myids", new Object[]{1, 2, 3, 4, 5}) .list(); //查询2008年2月创建的学生 List students = session.createQuery("select s.id, s.name from Student s where date_format(s.createTime, '%Y-%m')=?") .setParameter(0, "2008-02") .list(); //查询2008-01-10到2008-02-15创建的学生 List students = session.createQuery("select s.id, s.name from Student s where s.createTime between ? and ?") .setParameter(0, sdf.parse("2008-01-10 00:00:00")) .setParameter(1, sdf.parse("2008-02-15 23:59:59")) .list();