~~~~~~~~~~~~~~~~~~~~~~~~~~~~使用注解的方式配置事务~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
BookShopDao.java
package com.baidu.spring.DAO;
public interface BookShopDao {
//根据书号获取书的单价
public int findBookPriceByIsbn(String isbn);
//更新书的库存:使书号对应的库存-1
public void updateBookStock(String isbn);
//更新用户的账户余额:使username 的balance - price
public void updateUserAccount(String username,int price);
}
BookShopService.java
package com.baidu.spring.DAO;
public interface BookShopService {
public void purchase(String username,String isbn);
}
BookStockException.java
package com.baidu.spring.excption;
public class BookStockException extends RuntimeException {
private static final long serialVersionUID = 1L;
public BookStockException() {
super();
}
public BookStockException(String message) {
super(message);
}
}
UserAccountException.java
package com.baidu.spring.excption;
public class UserAccountException extends RuntimeException {
private static final long serialVersionUID = 1L;
public UserAccountException() {
super();
}
public UserAccountException(String message) {
super(message);
}
}
BookShopDaoImpl.java
package com.baidu.spring.impl;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.jdbc.core.JdbcTemplate;
import org.springframework.stereotype.Repository;
import com.baidu.spring.DAO.BookShopDao;
import com.baidu.spring.excption.BookStockException;
import com.baidu.spring.excption.UserAccountException;
@Repository
public class BookShopDaoImpl implements BookShopDao {
@Autowired
private JdbcTemplate jdbcTemplate;
@Override
public int findBookPriceByIsbn(String isbn) {
String sql = "SELECT price From book WHERE isbn = ?";
return jdbcTemplate.queryForObject(sql,Integer.class, isbn);
}
@Override
public void updateBookStock(String isbn) {
String sqlString = "SELECT stock FROM book_stock WhERE isbn = ?";
int stock = jdbcTemplate.queryForObject(sqlString, Integer.class,isbn);
if(stock == 0) {
throw new BookStockException("库存不足");
}
String sql = "UPDATE book_stock SET stock = stock - 1 WHERE isbn = ?";
jdbcTemplate.update(sql ,isbn);
}
@Override
public void updateUserAccount(String username, int price) {
String sqlString = "SELECT balance FROM account WhERE username = ?";
int balance = jdbcTemplate.queryForObject(sqlString, Integer.class,username);
if(balance < price) {
throw new UserAccountException("余额不足");
}
String sql = "UPDATE account SET balance = balance - ? WHERE username = ?";
jdbcTemplate.update(sql ,price,username);
}
}
BookShopServiceImpl.java
package com.baidu.spring.impl;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import org.springframework.transaction.annotation.Transactional;
import com.baidu.spring.DAO.BookShopDao;
import com.baidu.spring.DAO.BookShopService;
@Service("bookShopService")
public class BookShopServiceImpl implements BookShopService {
@Autowired
private BookShopDao bookShopDao;
@Transactional
@Override
public void purchase(String username, String isbn) {
//1.获取数的单价
int price = bookShopDao.findBookPriceByIsbn(isbn);
//2. 更新书的库存
bookShopDao.updateBookStock(isbn);
//3. 更新用户余额
bookShopDao.updateUserAccount(username, price);
}
}
TestTransactionManage.java
package com.baidu.spring.test;
import java.sql.SQLException;
import javax.sql.DataSource;
import org.junit.Test;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;
import com.baidu.spring.DAO.BookShopDao;
import com.baidu.spring.DAO.BookShopService;
public class TestTransactionManage {
private ApplicationContext ctx = null;
private BookShopDao bookShopDao = null;
private BookShopService bookShopService = null;
{
ctx = new ClassPathXmlApplicationContext("applicationcontext.xml");
bookShopDao = ctx.getBean(BookShopDao.class);
bookShopService = ctx.getBean(BookShopService.class);
}
//测试数据库连接
@Test
public void testDataSource() throws SQLException {
DataSource dataSource = ctx.getBean(DataSource.class);
System.out.println(dataSource.getConnection());
}
//测试方法findBookPriceByIsbn
@Test
public void testBookShopDao() {
System.out.println(bookShopDao.findBookPriceByIsbn("1001"));
}
//更新书的库存:使书号对应的库存-1
@Test
public void testUpdateBookStock() {
bookShopDao.updateBookStock("1001");
}
//更新用户的账户余额:使username 的balance - price
@Test
public void testUpdateUserAccount() {
bookShopDao.updateUserAccount("aa", 200);
}
@Test
public void testPurchase() {
bookShopService.purchase("AA", "1002");
}
}
<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:context="http://www.springframework.org/schema/context"
xmlns:tx="http://www.springframework.org/schema/tx"
xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd
http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-4.3.xsd
http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-4.3.xsd">
<!-- 自动扫描包 -->
<context:component-scan base-package="com.baidu.spring"></context:component-scan>
<!-- ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 配置c3p0 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~-->
<!-- 导入c3p0 资源文件 -->
<context:property-placeholder location="classpath:db.properties"/>
<!-- 配置c3p0 数据源 -->
<bean id="dataSource"
class="com.mchange.v2.c3p0.ComboPooledDataSource">
<property name="user" value="${jdbc.user}"></property>
<property name="password" value="${jdbc.password}"></property>
<property name="driverClass" value="${jdbc.driverClass}"></property>
<property name="jdbcUrl" value="${jdbc.jdbcUrl}"></property>
<property name="initialPoolSize" value="${jdbc.initPoolSize}"></property>
<property name="maxPoolSize" value="${jdbc.maxPoolSize}"></property>
</bean>
<!-- ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 配置 Spring 的 JdbcTemplate ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~-->
<bean id="jdbcTemplate"
class="org.springframework.jdbc.core.JdbcTemplate">
<property name="dataSource" ref="dataSource"></property>
</bean>
<!-- ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 事务管理 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~-->
<!-- 配置事务管理器 -->
<bean id="transactionManager"
class="org.springframework.jdbc.datasource.DataSourceTransactionManager">
<property name="dataSource" ref="dataSource"></property>
</bean>
<!-- 启用事务注解
如果事务管理器中的id 配置的就是transactionManager
则 transaction-manager="transactionManager" 可以省略 ,否则不能省略
-->
<tx:annotation-driven transaction-manager="transactionManager" />
</beans>
db.properties
jdbc.user=root
jdbc.password=12346
jdbc.driverClass=com.mysql.jdbc.Driver
jdbc.jdbcUrl=jdbc:mysql:///spring
jdbc.initPoolSize=5
jdbc.maxPoolSize=10
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~分割线~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
添加的接口:Cashier.java
package com.baidu.spring.DAO;
import java.util.List;
public interface Cashier {
public void checkOut(String username,List<String> isbns);
}
CashierImpl.javapackage com.baidu.spring.impl;
import java.util.List;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import org.springframework.transaction.annotation.Transactional;
import com.baidu.spring.DAO.BookShopService;
import com.baidu.spring.DAO.Cashier;
@Service("cashier")
public class CashierImpl implements Cashier {
@Autowired
private BookShopService bookShopService;
@Transactional
@Override
public void checkOut(String username, List<String> isbns) {
for(String isbn:isbns) {
bookShopService.purchase(username, isbn);
}
}
}
BookShopServiceImpl.javapackage com.baidu.spring.impl;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import org.springframework.transaction.annotation.Isolation;
import org.springframework.transaction.annotation.Propagation;
import org.springframework.transaction.annotation.Transactional;
import com.baidu.spring.DAO.BookShopDao;
import com.baidu.spring.DAO.BookShopService;
@Service("bookShopService")
public class BookShopServiceImpl implements BookShopService {
@Autowired
private BookShopDao bookShopDao;
/**
* 1. 事务的传播行为
* 使用propagation 指定事务的传播行为,即当前的 事务方法被另外的一个事务方法调用时,如何使用事务,
* ①. 默认取值为:REQUIRED,即使用调用方法的事务,
* ②. REQUIRES_NEW 使用自己的事务,调用方法的事务被挂起
*
* 2. 事务的隔离级别
* 使用isolation 指定事务的隔离级别
* ①. 常用的取值为:READ_COMMITTED,读已提交
* 3. 默认情况下Spring 的声明式事务对所有的运行时回滚,也可以通过对应的属性进行设置
* 通常情况下,默认取值即可。
* @Transactional(propagation=Propagation.REQUIRES_NEW,
* isolation=Isolation.READ_COMMITTED,
* noRollbackFor= {UserAccountException.class})
* 4. 使用readOnly 指定事务是否为只读,表示这个事务只读取数据但不更新数据,
* 这样可以帮助数据库引擎优化事务。若真的是一个只读取数据库值的方法,应设置readOnly=true
*
* 5. 使用timeout 指定强制回滚之前事务可以占用的时间。
*
*/
//添加事务注解
@Transactional(propagation=Propagation.REQUIRED,
isolation=Isolation.READ_COMMITTED,
readOnly=false,timeout=3)
@Override
public void purchase(String username, String isbn) {
try {
Thread.sleep(5000);
} catch (InterruptedException e) {}
//1.获取数的单价
int price = bookShopDao.findBookPriceByIsbn(isbn);
//2. 更新书的库存
bookShopDao.updateBookStock(isbn);
//3. 更新用户余额
bookShopDao.updateUserAccount(username, price);
}
}
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~分割线~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
~~~~~~~~~~~~~~~~~~~~~~~~~~~~使用XML的方式配置事务~~~~~~~~~~~~~~~~~~~~~~~~~~~~
去除注解,其他的都没变:
配置bean
<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:context="http://www.springframework.org/schema/context"
xmlns:tx="http://www.springframework.org/schema/tx"
xmlns:aop="http://www.springframework.org/schema/aop"
xsi:schemaLocation="http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-4.3.xsd
http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd
http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-4.3.xsd
http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-4.3.xsd">
<!-- 自动扫描包 -->
<context:component-scan base-package="com.baidu.springXML"></context:component-scan>
<!-- ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 配置c3p0 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~-->
<!-- 导入c3p0 资源文件 -->
<context:property-placeholder location="classpath:db.properties"/>
<!-- 配置c3p0 数据源 -->
<bean id="dataSource"
class="com.mchange.v2.c3p0.ComboPooledDataSource">
<property name="user" value="${jdbc.user}"></property>
<property name="password" value="${jdbc.password}"></property>
<property name="driverClass" value="${jdbc.driverClass}"></property>
<property name="jdbcUrl" value="${jdbc.jdbcUrl}"></property>
<property name="initialPoolSize" value="${jdbc.initPoolSize}"></property>
<property name="maxPoolSize" value="${jdbc.maxPoolSize}"></property>
</bean>
<!-- ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 配置 Spring 的 JdbcTemplate ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~-->
<bean id="jdbcTemplate"
class="org.springframework.jdbc.core.JdbcTemplate">
<property name="dataSource" ref="dataSource"></property>
</bean>
<!-- ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 配置Bean ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~-->
<bean id="bookShopDao" class="com.baidu.springXML.impl.BookShopDaoImpl">
<property name="jdbcTemplate" ref="jdbcTemplate"></property>
</bean>
<bean id="bookShopService" class="com.baidu.springXML.impl.service.BookShopServiceImpl">
<property name="bookShopDao" ref="bookShopDao"></property>
</bean>
<bean id="cashier" class="com.baidu.springXML.impl.service.CashierImpl">
<property name="bookShopService" ref="bookShopService"></property>
</bean>
<!-- ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 事务管理 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~-->
<!-- 1.配置事务管理器 -->
<bean id="transactionManager"
class="org.springframework.jdbc.datasource.DataSourceTransactionManager">
<property name="dataSource" ref="dataSource"></property>
</bean>
<!--2. 配置事务属性
* 1. 事务的传播行为
* 指定事务的传播行为,即当前的 事务方法被另外的一个事务方法调用时,如何使用事务,
* ①. 默认取值为:REQUIRED,即使用调用方法的事务,
* ②. REQUIRES_NEW 使用自己的事务,调用方法的事务被挂起
*
* 2. 事务的隔离级别
* 指定事务的隔离级别
* ①. 常用的取值为:READ_COMMITTED,读已提交
* 3. 默认情况下Spring 的声明式事务对所有的运行时回滚,也可以通过对应的属性进行设置
* 通常情况下,默认取值即可。
* rollbackFor= {UserAccountException.class})
* 4. 使用readOnly 指定事务是否为只读,表示这个事务只读取数据但不更新数据,
* 这样可以帮助数据库引擎优化事务。若真的是一个只读取数据库值的方法,应设置readOnly=true
*
* 5. 使用timeout 指定强制回滚之前事务可以占用的时间。
-->
<tx:advice id="txAdvice" transaction-manager="transactionManager">
<tx:attributes>
<!-- 根据方法名指定事务的属性 -->
<tx:method name="purchase" propagation="REQUIRES_NEW" />
<tx:method name="get*" read-only="true"/>
<tx:method name="find*" read-only="true"/>
<tx:method name="*"/>
</tx:attributes>
</tx:advice>
<!-- 3. 配置事务切入点,以及把事务切入点和事务属性关联起来 -->
<aop:config>
<aop:pointcut expression="execution(* com.baidu.springXML.impl.service.*.*(..)))"
id="txPointcut"/>
<aop:advisor advice-ref="txAdvice" pointcut-ref="txPointcut"/>
</aop:config>
</beans>