对象增删改查与SQL查询操作方法

对象增删改查与SQL查询操作方法。

packageDao;

importjava.util.List;

importorg.hibernate.Query;

importorg.hibernate.Session;

importorg.hibernate.Transaction;

importorg.junit.Test;

importdomain.User;

importutils.HibernateUtils;

publicclassUserDao{

//增加用户

@Test

publicvoidaddUser(){

Sessionsession=null;

Transactionts=null;

try{

session=HibernateUtils.getSession();

ts=session.beginTransaction();

Useruser=newUser();//瞬时对象

user.setName("小王");

user.setSex("女");

user.setAge(33);

user.setHeight(180);

user.setHobby("做饭");

session.save(user);//持久对象

ts.commit();

}catch(Exceptione){

if(ts!=null)

{

ts.rollback();

}

e.printStackTrace();

}

}

//查询用户

@Test

publicvoidfindUser(){

Sessionsession=null;

Transactionts=null;

try{

session=HibernateUtils.getSession();

ts=session.beginTransaction();

Useruser=session.get(User.class,4);//持久对象

System.out.println(user);

ts.commit();

}catch(Exceptione){

if(ts!=null)

{

ts.rollback();

}

e.printStackTrace();

}

}

//修改用户

@Test

publicvoidupdateUser(){

Sessionsession=null;

Transactionts=null;

try{

session=HibernateUtils.getSession();

ts=session.beginTransaction();

Useruser=session.get(User.class,4);

user.setAge(25);

user.setHobby("吃饭");

session.update(user);//持久对象

System.out.println(user);

ts.commit();

}catch(Exceptione){

if(ts!=null)

{

ts.rollback();

}

e.printStackTrace();

}

}

//删除用户

@Test

publicvoiddeleteUser(){

Sessionsession=null;

Transactionts=null;

try{

session=HibernateUtils.getSession();

ts=session.beginTransaction();

Useruser=session.get(User.class,6);

session.delete(user);

System.out.println(user);

ts.commit();

}catch(Exceptione){

if(ts!=null)

{

ts.rollback();

}

e.printStackTrace();

}

}

//简单查询

@Test

publicvoidqueryUser(){

Sessionsession=null;

Transactionts=null;

try{

session=HibernateUtils.getSession();

ts=session.beginTransaction();

Queryquery=session.createQuery("fromUser");

Listusers=query.list();

for(Useruser:users){

System.out.println(user);

}

ts.commit();

}catch(Exceptione){

if(ts!=null)

{

ts.rollback();

}

e.printStackTrace();

}

}

//属性查询

@Test

publicvoidqueryUserName(){

Sessionsession=null;

Transactionts=null;

try{

session=HibernateUtils.getSession();

ts=session.beginTransaction();

Queryquery=session.createQuery("selectu.namefromUseru");

Listnames=query.list();

for(Stringuser:names){

System.out.println(user);

}

ts.commit();

}catch(Exceptione){

if(ts!=null)

{

ts.rollback();

}

e.printStackTrace();

}

}

//实例化查询

@Test

publicvoidqueryUserExample(){

Sessionsession=null;

Transactionts=null;

try{

session=HibernateUtils.getSession();

ts=session.beginTransaction();

Queryquery=session.createQuery("fromUserwhereage=21");

Listusers=query.list();

for(Useruser:users){

System.out.println(user);

}

ts.commit();

}catch(Exceptione){

if(ts!=null)

{

ts.rollback();

}

e.printStackTrace();

}

}

//统计查询

@Test

publicvoidqueryUserGroup(){

Sessionsession=null;

Transactionts=null;

try{

session=HibernateUtils.getSession();

ts=session.beginTransaction();

Queryquery=session.createQuery("selectavg(u.age)fromUseru");

Numberavgage=(Number)query.uniqueResult();

System.out.println("平均年龄为："+avgage);

ts.commit();

}catch(Exceptione){

if(ts!=null)

{

ts.rollback();

}

e.printStackTrace();

}

}

//子查询

@Test

publicvoidqueryUserIn(){

Sessionsession=null;

Transactionts=null;

try{

session=HibernateUtils.getSession();

ts=session.beginTransaction();

Queryquery=session.createQuery("fromUseruwhereu.age>(selectavg(age)fromUser)");

Useruser=null;

Listlist=query.list();

for(inti=0;iuser=(User)list.get(i);

System.out.println(i+"姓名："+user.getName()+"——年龄："+user.getAge());

}

ts.commit();

}catch(Exceptione){

if(ts!=null)

{

ts.rollback();

}

e.printStackTrace();

}

}

}