7
votes
package com.bluesky;

public interface FooServiceIface {
    public  void insertA();
    public void insertB();
}

package com.bluesky;

import org.springframework.jdbc.core.support.JdbcDaoSupport;

public class FooServiceImpl extends JdbcDaoSupport implements FooServiceIface {

    public void insertA() {
        this.getJdbcTemplate().execute("insert student(name) values('stuA')");
         insertB();
         int i=10/0;
    }

    public void insertB() {
        this.getJdbcTemplate().execute("insert student(name) values('stuB')");

    }

}

public class Client {

    public static void main(String[] args) {

        ApplicationContext appContxt = new ClassPathXmlApplicationContext("applicationContext.xml");

        FooServiceIface  fService= (FooServiceIface)appContxt.getBean("fooService");

        fService.insertA();

    }
}

<?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:tx="http://www.springframework.org/schema/tx"
    xsi:schemaLocation="http://www.springframework.org/schema/beans
           http://www.springframework.org/schema/beans/spring-beans-2.5.xsd
           http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-2.5.xsd
           http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-2.5.xsd">

    <bean id="dataSource" class="org.springframework.jdbc.datasource.DriverManagerDataSource">
       <property name="driverClassName" value="com.mysql.jdbc.Driver"/>
       <property name="url" value="jdbc:mysql://localhost:3306/test?useUnicode=true&amp;characterEncoding=utf-8"/>
       <property name="username" value="root"/>
       <property name="password" value="root"/>
    </bean>

    <bean id="fooService" class="com.bluesky.FooServiceImpl">
         <property name="dataSource" ref="dataSource"/>  
    </bean>
    <bean id="transactionManager" class="org.springframework.jdbc.datasource.DataSourceTransactionManager">  
        <property name="dataSource" ref="dataSource"/>  
    </bean>  

    <tx:advice id="txAdvice" transaction-manager="transactionManager">
        <tx:attributes>
            <tx:method name="insertA" propagation="REQUIRED" />
             <tx:method name="insertB" propagation="REQUIRES_NEW" />
        </tx:attributes>
    </tx:advice>

    <aop:config proxy-target-class="true">
        <aop:pointcut id="interceptorPointCuts" expression="execution(* com.bluesky.*Service*.*(..))" />
        <aop:advisor advice-ref="txAdvice" pointcut-ref="interceptorPointCuts" />       
    </aop:config>     
</beans>

Sorry for the Complicated code

When i run Client blow debug logs are showing:

21:44:19,546 DEBUG TransactionSynchronizationManager:183 - Bound value [org.springframework.jdbc.datasource.ConnectionHolder@ba86ef] for key [org.springframework.jdbc.datasource.DriverManagerDataSource@1b9658e] to thread [main]
21:44:19,546 DEBUG TransactionSynchronizationManager:258 - Initializing transaction synchronization
21:44:19,547 DEBUG TransactionInterceptor:362 - Getting transaction for [com.bluesky.FooServiceImpl.insertA]
21:44:19,547 DEBUG JdbcTemplate:416 - Executing SQL statement [insert student(name) values('stuA')]
21:44:19,592 DEBUG JdbcTemplate:416 - Executing SQL statement [insert student(name) values('stuB')]
21:44:19,594 DEBUG TransactionInterceptor:406 - Completing transaction for [com.bluesky.FooServiceImpl.insertA] after exception: java.lang.ArithmeticException: / by zero
21:44:19,594 DEBUG RuleBasedTransactionAttribute:130 - Applying rules to determine whether transaction should rollback on java.lang.ArithmeticException: / by zero
21:44:19,594 DEBUG RuleBasedTransactionAttribute:147 - Winning rollback rule is: null
21:44:19,595 DEBUG RuleBasedTransactionAttribute:152 - No relevant rollback rule found: applying default rules
21:44:19,595 DEBUG DataSourceTransactionManager:938 - Triggering beforeCompletion synchronization
21:44:19,595 DEBUG DataSourceTransactionManager:843 - Initiating transaction rollback
21:44:19,596 DEBUG DataSourceTransactionManager:279 - Rolling back JDBC transaction on Connection [com.mysql.jdbc.JDBC4Connection@167f4bf]
21:44:19,598 DEBUG DataSourceTransactionManager:967 - Triggering afterCompletion synchronization
21:44:19,598 DEBUG TransactionSynchronizationManager:316 - Clearing transaction synchronization

I found that when invoked insertA() method , this method start a transaction, when the code arrive insertB(), there is not transaction for starting.

Is there anything did i not configured or any concern i made mistaken

My intention is to when insertA() call insertB() there is an REQUIRES_NEW transaction start.

3

3 Answers

5
votes

KLE's advice about refactoring your code is right on the money, but as for why it's not working, Spring AOP uses JDK dynamic proxies by default to provide AOP. That means that when you inject your service into something, what's really getting injected is a Proxy instance that implements your service interface. When a method is invoked on this proxy, it runs the transaction code before delegating to your actual service instance. Once the control flow is inside your service, though, calling another method via this.foo() (even if the this is implicit) just invokes a method on that same instance: your service. It doesn't go back to the proxy, which is the only thing that knows about transactions. If you switched to build- or load-time bytecode weaving with AspectJ, then you could do this, and it would work as expected, since the transaction-invoking code would be woven directly into your service code instead of living in a separate object.

4
votes

I understand your problem. There are some technically complex ways to get it work, but we don't usually consider they are worth it. I suggest another approach, simple and powerful, that actually improves your code.

Instead of having them on the same Spring bean, have them on two different Beans, B being injected into A.

I known I'm not answering your question, but think about the advantages :

  • Dead simple, it will cost you very little time now.
  • To require a new transaction, B is probably a different concern. Having a different concern is a different class seem exactly what we are looking for, good design.
  • You don't have anything new and complex to explain to your colleagues (or document for the future developers), it simplicity makes it immediately understandable.
2
votes

KLE's answer is solid advice. Just to complete the picture, there is a workaround, but it breaks everything AOP stands for:

public void insertA() {
    this.getJdbcTemplate().execute("insert student(name) values('stuA')");
    // this works, but... gah!
    ((FooServiceIface) AopContext.currentProxy()).insertB();
    int i=10/0;
}

Reference: