String整合hibernate代码测试
在上节生成的表中插入数据：
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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。
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第一步 我们写dao接口
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package com.ssh.spring_hibernate.dao; ? public ????//根据书号获取数的单价 ????public ???? ????//更新书的库存，使书号对应的库存-1 ????public ???? ????//更新用户的账户余额：使username的balance-price ????public } |
写好其实现类
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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 ???? */ ???? [email protected] ????private SessionFactory sessionFactory; ???? ????public Session getSession(){ ????????return sessionFactory.getCurrentSession(); ????} [email protected] ????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(); ????} ? [email protected] ????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(); ????} ? [email protected] ????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); ????} ? } |
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注意：需要在spring的配置文件中添加自动扫描的路径
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<!-- 设置自动扫描的包--> ????<context:component-scan |
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第二步写好service
public
interface BookShopService {
????public
void
purchase(String username,String isbn);
}
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public
interface
Cashier {
????public
void checkout(String username,List<String>isbn);
}
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其实现类
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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{ [email protected] ????private BookShopDao bookShopDao; ???? [email protected] ????public void purchase(String username, String isbn) { ????????int price =bookShopDao.findBookPriceByIsbn(isbn); ????????bookShopDao.updataBookStock(isbn); ????????bookShopDao.updateUserAccount(username, price); ????} ? } |
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package com.ssh.spring_hibernate.service; ? import java.util.List; ? import org.springframework.beans.factory.annotation.Autowired; import org.springframework.stereotype.Service; ? @Service public ????@Autowired ????private BookShopService bookShopService; ???? ????@Override ????public ????????for (String is : isbn) { ????????????bookShopService.purchase(username, is); ????????} ???????? ????} ? } |
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第三步写我们的测试类
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public class Go { ???? ????private ApplicationContext ctx=new ClassPathXmlApplicationContext("applicationContext.xml"); ????private BookShopService bookShopService=null; ????{ ????????bookShopService=ctx.getBean(BookShopService.class); ????} ???? ????public ????????DataSource d=ctx.getBean(DataSource.class); ????????System.out.println(d.getConnection()); ????} ???? ????public ????????bookShopService.purchase("aa", "1002"); ????} ????public ????????new Go().testBookShopService(); ????} } |
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控制台打印
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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 |
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Spring Hibernate 事务的流程
- 在方法之前
- 获取Session
- 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
- 开启事务
- 若方法正常结束，即没有出现异常，则
- 提交事务
- 使和当前线程绑定的Session解除绑定
- 关闭Session
3若方法出现异常，则
????① 回滚事务
- 使和当前线程绑定的Session解除绑定
- 关闭Session