pom.xml:

<dependencies>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-context</artifactId>
<version>5.0.2.RELEASE</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-test</artifactId>
<version>5.0.2.RELEASE</version>
</dependency>
<dependency>
<groupId>commons-dbutils</groupId>
<artifactId>commons-dbutils</artifactId>
<version>1.4</version>
</dependency>

<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<version>5.1.6</version>
</dependency>

<dependency>
<groupId>c3p0</groupId>
<artifactId>c3p0</artifactId>
<version>0.9.1.2</version>
</dependency>

<dependency>
<groupId>junit</groupId>
<artifactId>junit</artifactId>
<version>4.12</version>
</dependency>
<dependency>
<groupId>org.aspectj</groupId>
<artifactId>aspectjweaver</artifactId>
<version>1.8.7</version>
</dependency>
</dependencies>

bean.xml:

<?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:aop="http://www.springframework.org/schema/aop"
xmlns:context="http://www.springframework.org/schema/context"
xsi:schemaLocation="http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans.xsd
http://www.springframework.org/schema/aop
http://www.springframework.org/schema/aop/spring-aop.xsd
http://www.springframework.org/schema/context
http://www.springframework.org/schema/context/spring-context.xsd">

<!--配置spring创建容器时要扫描的包-->
<context:component-scan base-package="com.itheima"></context:component-scan>

<!--配置QueryRunner-->
<bean id="runner" class="org.apache.commons.dbutils.QueryRunner" scope="prototype"></bean>

<!-- 配置数据源 -->
<bean id="dataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource">
<!--连接数据库的必备信息-->
<property name="driverClass" value="com.mysql.jdbc.Driver"></property>
<property name="jdbcUrl" value="jdbc:mysql://localhost:3306/eesy"></property>
<property name="user" value="root"></property>
<property name="password" value="1234"></property>
</bean>

<!--开启spring对注解AOP的支持-->
<aop:aspectj-autoproxy></aop:aspectj-autoproxy>
</beans>

ConnectionUtils:

/**
* 连接的工具类，它用于从数据源中获取一个连接，并且实现和线程的绑定
*/
@Component("connectionUtils")
public class ConnectionUtils {

private ThreadLocal<Connection> tl = new ThreadLocal<Connection>();

@Autowired
private DataSource dataSource;

/**
* 获取当前线程上的连接
* @return
*/
public Connection getThreadConnection() {
try{
//1.先从ThreadLocal上获取
Connection conn = tl.get();
//2.判断当前线程上是否有连接
if (conn == null) {
//3.从数据源中获取一个连接，并且存入ThreadLocal中
conn = dataSource.getConnection();
tl.set(conn);
}
//4.返回当前线程上的连接
return conn;
}catch (Exception e){
throw new RuntimeException(e);
}
}

/**
* 把连接和线程解绑
*/
public void removeConnection(){
tl.remove();
}
}

AccountDaoImpl:

/**
* 账户的持久层实现类
*/
@Repository("accountDao")
public class AccountDaoImpl implements IAccountDao {

@Autowired
private QueryRunner runner;

@Autowired
private ConnectionUtils connectionUtils;

@Override
public List<Account> findAllAccount() {
try{
return runner.query(connectionUtils.getThreadConnection(),"select * from account",new BeanListHandler<Account>(Account.class));
}catch (Exception e) {
throw new RuntimeException(e);
}
}

....

AccountServiceImpl:

@Service("accountService")
public class AccountServiceImpl implements IAccountService{

@Autowired
private IAccountDao accountDao;

@Override
public List<Account> findAllAccount() {
return accountDao.findAllAccount();
}

        ...

@Override
public void transfer(String sourceName, String targetName, Float money) {
System.out.println("transfer....");
//2.1根据名称查询转出账户
Account source = accountDao.findAccountByName(sourceName);
//2.2根据名称查询转入账户
Account target = accountDao.findAccountByName(targetName);
//2.3转出账户减钱
source.setMoney(source.getMoney()-money);
//2.4转入账户加钱
target.setMoney(target.getMoney()+money);
//2.5更新转出账户
accountDao.updateAccount(source);

int i=1/0;

//2.6更新转入账户
accountDao.updateAccount(target);
}

...

TransactionManager:

注意：因为分别配置前置通知后置通知会存在顺序问题

1.前置通知2.最终通知释放资源导致连接被回收3.执行方法4.后置通知/异常通知

所以一般会配置环绕通知来解决。

/**
* 和事务管理相关的工具类，它包含了，开启事务，提交事务，回滚事务和释放连接
*/
@Component("txManager")
@Aspect
public class TransactionManager {

@Autowired
private ConnectionUtils connectionUtils;

@Pointcut("execution(* com.itheima.service.impl.*.*(..))")
private void pt1(){}

/**
* 开启事务
*/
public  void beginTransaction(){
try {
connectionUtils.getThreadConnection().setAutoCommit(false);
}catch (Exception e){
e.printStackTrace();
}
}

/**
* 提交事务
*/
public  void commit(){
try {
connectionUtils.getThreadConnection().commit();
}catch (Exception e){
e.printStackTrace();
}
}

/**
* 回滚事务
*/
public  void rollback(){
try {
connectionUtils.getThreadConnection().rollback();
}catch (Exception e){
e.printStackTrace();
}
}

/**
* 释放连接
*/
public  void release(){
try {
connectionUtils.getThreadConnection().close();//还回连接池中
connectionUtils.removeConnection();
}catch (Exception e){
e.printStackTrace();
}
}

@Around("pt1()")
public Object aroundAdvice(ProceedingJoinPoint pjp){
Object rtValue = null;
try {
//1.获取参数
Object[] args = pjp.getArgs();
//2.开启事务
this.beginTransaction();
//3.执行方法
rtValue = pjp.proceed(args);
//4.提交事务
this.commit();

//返回结果
return  rtValue;

}catch (Throwable e){
//5.回滚事务
this.rollback();
throw new RuntimeException(e);
}finally {
//6.释放资源
this.release();
}
}
}

测试类：

/**
* 使用Junit单元测试：测试我们的配置
*/
@RunWith(SpringJUnit4ClassRunner.class)
@ContextConfiguration(locations = "classpath:bean.xml")
public class AccountServiceTest {

@Autowired
private  IAccountService as;

@Test
public  void testTransfer(){
as.transfer("aaa","bbb",100f);
}

}