Spring笔记⑤--整合hibernate代码测试

String整合hibernate代码测试

在上节生成的表中插入数据：

 

注意：使用myeclipse2014生成的整合项目可能存在问题需要我们自己导入。

 

第一步 我们写dao接口

package com.ssh.spring_hibernate.dao;

 

public interface BookShopDao {

    //根据书号获取数的单价

    public int findBookPriceByIsbn(String isbn);

    

    //更新书的库存，使书号对应的库存-1

    public void updataBookStock(String isbn);

    

    //更新用户的账户余额：使username的balance-price

    public void updateUserAccount(String username,int price);

}

写好其实现类

package com.ssh.spring_hibernate.dao;

 

import org.hibernate.Query;

import org.hibernate.Session;

import org.hibernate.SessionFactory;

import org.springframework.beans.factory.annotation.Autowired;

import org.springframework.stereotype.Repository;

@Repository

public class BookShopDaoImpl implements BookShopDao {

    /**

     * 怎么用hibernate

     * 从SessionFactory中拿到跟当前线程绑定的Session

     */

    

    @Autowired

    private SessionFactory sessionFactory;

    

    public Session getSession(){

        return sessionFactory.getCurrentSession();

    }

    @Override

    public int findBookPriceByIsbn(String isbn) {

        String hql="select b.price from Book b where b.isbn=?";

        Query q=getSession().createQuery(hql).setString(0, isbn);

        return (Integer) q.uniqueResult();

    }

 

    @Override

    public void updataBookStock(String isbn) {

        //验证书的库存是否足够

        String hql2="select b.stock from Book b where b.isbn=?";

        int stock=(Integer) getSession().createQuery(hql2).setString(0, isbn).uniqueResult();

        if (stock==0) {

            System.out.println("库存不足！");

        }

        String hql="update Book b set b.stock=b.stock-1 where b.isbn=?";

        getSession().createQuery(hql).setString(0, isbn).executeUpdate();

    }

 

    @Override

    public void updateUserAccount(String username, int price) {

        //验证余额是否足够

        String hql2="select a.balance from Account a where a.username=?";

        int balance=(Integer) getSession().createQuery(hql2).setString(0, username).uniqueResult();

        System.out.println(balance);

        if (balance<price) {

            System.out.println("余额不足");

        }

        int result=balance-price;

        String hql="update Account a set a.balance=? where a.username=?";

        getSession().createQuery(hql).setInteger(0, result).setString(1, username).executeUpdate();

        System.out.println("余额为"+result);

    }

 

}

 

注意：需要在spring的配置文件中添加自动扫描的路径

<!-- 设置自动扫描的包-->

    <context:component-scan base-package="com.ssh.spring_hibernate"></context:component-scan>

 

第二步写好service

public interface BookShopService {

    public void purchase(String username,String isbn);

}

 

 

public interface Cashier {

    public void checkout(String username,List<String>isbn);

}

 

其实现类

package com.ssh.spring_hibernate.service;

 

import org.springframework.beans.factory.annotation.Autowired;

import org.springframework.stereotype.Service;

 

import com.ssh.spring_hibernate.dao.BookShopDao;

 

@Service

public class BookShopServiceImpl implements BookShopService{

    @Autowired

    private BookShopDao bookShopDao;

    

    @Override

    public void purchase(String username, String isbn) {

        int price =bookShopDao.findBookPriceByIsbn(isbn);

        bookShopDao.updataBookStock(isbn);

        bookShopDao.updateUserAccount(username, price);

    }

 

}

 

package com.ssh.spring_hibernate.service;

 

import java.util.List;

 

import org.springframework.beans.factory.annotation.Autowired;

import org.springframework.stereotype.Service;

 

@Service

public class CashierImpl implements Cashier {

    @Autowired

    private BookShopService bookShopService;

    

    @Override

    public void checkout(String username, List<String> isbn) {

        for (String is : isbn) {

            bookShopService.purchase(username, is);

        }

        

    }

 

}

 

第三步写我们的测试类

public class Go {

    

    private ApplicationContext ctx=new ClassPathXmlApplicationContext("applicationContext.xml");

    private BookShopService bookShopService=null;

    {

        bookShopService=ctx.getBean(BookShopService.class);

    }

    

    public void testDataSource () throws SQLException{

        DataSource d=ctx.getBean(DataSource.class);

        System.out.println(d.getConnection());

    }

    

    public void testBookShopService(){

        bookShopService.purchase("aa", "1002");

    }

    public static void main(String[] args) throws SQLException {

        new Go().testBookShopService();

    }

}

 

 

控制台打印

Hibernate:

select

book0_.PRICE as col_0_0_

from

SH_BOOK book0_

where

book0_.ISBN=?

Hibernate:

select

book0_.STOCK as col_0_0_

from

SH_BOOK book0_

where

book0_.ISBN=?

Hibernate:

update

SH_BOOK

set

STOCK=STOCK-1

where

ISBN=?

Hibernate:

select

account0_.BALANCE as col_0_0_

from

SH_ACCOUNT account0_

where

account0_.USER_NAME=?

230

Hibernate:

update

SH_ACCOUNT

set

BALANCE=?

where

USER_NAME=?

余额为160

 

 

Spring Hibernate 事务的流程

1. 在方法之前
   1. 获取Session
   2. 把Session和当前线程绑定，这样就可以在Dao中使用SessionFactory的getCurrentSession()方法来获取Session了
   3. 开启事务
2. 若方法正常结束，即没有出现异常，则
   1. 提交事务
   2. 使和当前线程绑定的Session解除绑定
   3. 关闭Session

3若方法出现异常，则

    ① 回滚事务

1. 使和当前线程绑定的Session解除绑定
2. 关闭Session