iBATIS事务处理
一：问题
最近发现了我们自己的项目的事务的处理根本就是行不通的，也因此我自己又去看了下有关事务的处理，算是有了个大致的了解吧，先说说我们最初的配置吧。
二：内容
（1）：使用iBatis的事务管理
SqlMapClient client = this.getSqlMap();
try {
client.startTransaction();
client.insert("addUser", user);
client.getCurrentConnection().commit();;
int i = 3/0;
} catch (Exception e) {
throw new RuntimeException();
}
这种形式下的事务根本就没有用处的，最后搜索了下，又看了相应的说明，发现如下：
所以，这里的事务写法就必须如下了
SqlMapClient client = this.getSqlMap();
try {
client.startTransaction();
//必须设置
client.getCurrentConnection().setAutoCommit(false);
client.insert("addUser", user);
client.getCurrentConnection().commit();;
int i = 3/0;
} catch (Exception e) {
throw new RuntimeException();
}
加上这段事务之后，经过测试后的确是可以回滚了。
（2）：使用spring来管理事务
在使用spring来管理事务的同时，也有两种形式：
(一)：使用注解
(二)：不使用注解，直接指定特定方法拦截，比如delete*,update*,save*等方法。
但是我们用的是spring4.1.11的jar文件，在使用注解的时候一直包错误
可以看看这个链接的说明http://zapone.org/bernadine/2015/01/07/nosuchmethoderror-aopnamespaceutils-registerautoproxycreatorifnecessarylorgspringframeworkbeansfactoryxmlparsercontextljavalangobjectv/
org.springframework.beans.factory.BeanDefinitionStoreException: Unexpected exception parsing XML document from file [D:\MyEclipse\wh\.metadata\.me_tcat7\webapps\graduate\WEB-INF\classes\applicationContext-bean.xml]; nested exception is java.lang.NoSuchMethodError: org.springframework.aop.config.AopNamespaceUtils.registerAutoProxyCreatorIfNecessary(Lorg/springframework/beans/factory/xml/ParserContext;Ljava/lang/Object;)V
at org.springframework.beans.factory.xml.XmlBeanDefinitionReader.doLoadBeanDefinitions(XmlBeanDefinitionReader.java:414)
at org.springframework.beans.factory.xml.XmlBeanDefinitionReader.loadBeanDefinitions(XmlBeanDefinitionReader.java:336)
at org.springframework.beans.factory.xml.XmlBeanDefinitionReader.loadBeanDefinitions(XmlBeanDefinitionReader.java:304)
at org.springframework.beans.factory.support.AbstractBeanDefinitionReader.loadBeanDefinitions(AbstractBeanDefinitionReader.java:180)
at org.springframework.beans.factory.support.AbstractBeanDefinitionReader.loadBeanDefinitions(AbstractBeanDefinitionReader.java:216)
at org.springframework.beans.factory.support.AbstractBeanDefinitionReader.loadBeanDefinitions(AbstractBeanDefinitionReader.java:187)
at org.springframework.web.context.support.XmlWebApplicationContext.loadBeanDefinitions(XmlWebApplicationContext.java:125)
at org.springframework.web.context.support.XmlWebApplicationContext.loadBeanDefinitions(XmlWebApplicationContext.java:94)
at org.springframework.context.support.AbstractRefreshableApplicationContext.refreshBeanFactory(AbstractRefreshableApplicationContext.java:129)
at org.springframework.context.support.AbstractApplicationContext.obtainFreshBeanFactory(AbstractApplicationContext.java:537)
at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:452)
at org.springframework.web.context.ContextLoader.configureAndRefreshWebApplicationContext(ContextLoader.java:403)
at org.springframework.web.context.ContextLoader.initWebApplicationContext(ContextLoader.java:306)
at org.springframework.web.context.ContextLoaderListener.contextInitialized(ContextLoaderListener.java:106)
at org.apache.catalina.core.StandardContext.listenerStart(StandardContext.java:4791)
at org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:5285)
at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:150)
at org.apache.catalina.core.ContainerBase.addChildInternal(ContainerBase.java:901)
at org.apache.catalina.core.ContainerBase.addChild(ContainerBase.java:877)
at org.apache.catalina.core.StandardHost.addChild(StandardHost.java:618)
at org.apache.catalina.startup.HostConfig.deployDirectory(HostConfig.java:1100)
at org.apache.catalina.startup.HostConfig$DeployDirectory.run(HostConfig.java:1618)
at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:471)
at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:334)
at java.util.concurrent.FutureTask.run(FutureTask.java:166)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
at java.lang.Thread.run(Thread.java:724)
Caused by: java.lang.NoSuchMethodError: org.springframework.aop.config.AopNamespaceUtils.registerAutoProxyCreatorIfNecessary(Lorg/springframework/beans/factory/xml/ParserContext;Ljava/lang/Object;)V
at org.springframework.transaction.config.AnnotationDrivenBeanDefinitionParser.parseInternal(AnnotationDrivenBeanDefinitionParser.java:54)
at org.springframework.beans.factory.xml.AbstractBeanDefinitionParser.parse(AbstractBeanDefinitionParser.java:60)
at org.springframework.beans.factory.xml.NamespaceHandlerSupport.parse(NamespaceHandlerSupport.java:74)
at org.springframework.beans.factory.xml.BeanDefinitionParserDelegate.parseCustomElement(BeanDefinitionParserDelegate.java:1427)
at org.springframework.beans.factory.xml.BeanDefinitionParserDelegate.parseCustomElement(BeanDefinitionParserDelegate.java:1417)
at org.springframework.beans.factory.xml.DefaultBeanDefinitionDocumentReader.parseBeanDefinitions(DefaultBeanDefinitionDocumentReader.java:174)
at org.springframework.beans.factory.xml.DefaultBeanDefinitionDocumentReader.doRegisterBeanDefinitions(DefaultBeanDefinitionDocumentReader.java:144)
at org.springframework.beans.factory.xml.DefaultBeanDefinitionDocumentReader.registerBeanDefinitions(DefaultBeanDefinitionDocumentReader.java:100)
at org.springframework.beans.factory.xml.XmlBeanDefinitionReader.registerBeanDefinitions(XmlBeanDefinitionReader.java:510)
at org.springframework.beans.factory.xml.XmlBeanDefinitionReader.doLoadBeanDefinitions(XmlBeanDefinitionReader.java:392)
... 27 more
五月 07, 2015 2:01:05 下午 org.apache.catalina.core.StandardContext listenerStart
SEVERE: Exception sending context initialized event to listener instance of class org.springframework.web.context.ContextLoaderListener
org.springframework.beans.factory.BeanDefinitionStoreException: Unexpected exception parsing XML document from file [D:\MyEclipse\wh\.metadata\.me_tcat7\webapps\graduate\WEB-INF\classes\applicationContext-bean.xml]; nested exception is java.lang.NoSuchMethodError: org.springframework.aop.config.AopNamespaceUtils.registerAutoProxyCreatorIfNecessary(Lorg/springframework/beans/factory/xml/ParserContext;Ljava/lang/Object;)V
at org.springframework.beans.factory.xml.XmlBeanDefinitionReader.doLoadBeanDefinitions(XmlBeanDefinitionReader.java:414)
at org.springframework.beans.factory.xml.XmlBeanDefinitionReader.loadBeanDefinitions(XmlBeanDefinitionReader.java:336)
at org.springframework.beans.factory.xml.XmlBeanDefinitionReader.loadBeanDefinitions(XmlBeanDefinitionReader.java:304)
at org.springframework.beans.factory.support.AbstractBeanDefinitionReader.loadBeanDefinitions(AbstractBeanDefinitionReader.java:180)
at org.springframework.beans.factory.support.AbstractBeanDefinitionReader.loadBeanDefinitions(AbstractBeanDefinitionReader.java:216)
at org.springframework.beans.factory.support.AbstractBeanDefinitionReader.loadBeanDefinitions(AbstractBeanDefinitionReader.java:187)
at org.springframework.web.context.support.XmlWebApplicationContext.loadBeanDefinitions(XmlWebApplicationContext.java:125)
at org.springframework.web.context.support.XmlWebApplicationContext.loadBeanDefinitions(XmlWebApplicationContext.java:94)
at org.springframework.context.support.AbstractRefreshableApplicationContext.refreshBeanFactory(AbstractRefreshableApplicationContext.java:129)
at org.springframework.context.support.AbstractApplicationContext.obtainFreshBeanFactory(AbstractApplicationContext.java:537)
at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:452)
at org.springframework.web.context.ContextLoader.configureAndRefreshWebApplicationContext(ContextLoader.java:403)
at org.springframework.web.context.ContextLoader.initWebApplicationContext(ContextLoader.java:306)
at org.springframework.web.context.ContextLoaderListener.contextInitialized(ContextLoaderListener.java:106)
at org.apache.catalina.core.StandardContext.listenerStart(StandardContext.java:4791)
at org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:5285)
at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:150)
at org.apache.catalina.core.ContainerBase.addChildInternal(ContainerBase.java:901)
at org.apache.catalina.core.ContainerBase.addChild(ContainerBase.java:877)
at org.apache.catalina.core.StandardHost.addChild(StandardHost.java:618)
at org.apache.catalina.startup.HostConfig.deployDirectory(HostConfig.java:1100)
at org.apache.catalina.startup.HostConfig$DeployDirectory.run(HostConfig.java:1618)
at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:471)
at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:334)
at java.util.concurrent.FutureTask.run(FutureTask.java:166)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
at java.lang.Thread.run(Thread.java:724)
Caused by: java.lang.NoSuchMethodError: org.springframework.aop.config.AopNamespaceUtils.registerAutoProxyCreatorIfNecessary(Lorg/springframework/beans/factory/xml/ParserContext;Ljava/lang/Object;)V
at org.springframework.transaction.config.AnnotationDrivenBeanDefinitionParser.parseInternal(AnnotationDrivenBeanDefinitionParser.java:54)
at org.springframework.beans.factory.xml.AbstractBeanDefinitionParser.parse(AbstractBeanDefinitionParser.java:60)
at org.springframework.beans.factory.xml.NamespaceHandlerSupport.parse(NamespaceHandlerSupport.java:74)
at org.springframework.beans.factory.xml.BeanDefinitionParserDelegate.parseCustomElement(BeanDefinitionParserDelegate.java:1427)
at org.springframework.beans.factory.xml.BeanDefinitionParserDelegate.parseCustomElement(BeanDefinitionParserDelegate.java:1417)
at org.springframework.beans.factory.xml.DefaultBeanDefinitionDocumentReader.parseBeanDefinitions(DefaultBeanDefinitionDocumentReader.java:174)
at org.springframework.beans.factory.xml.DefaultBeanDefinitionDocumentReader.doRegisterBeanDefinitions(DefaultBeanDefinitionDocumentReader.java:144)
at org.springframework.beans.factory.xml.DefaultBeanDefinitionDocumentReader.registerBeanDefinitions(DefaultBeanDefinitionDocumentReader.java:100)
at org.springframework.beans.factory.xml.XmlBeanDefinitionReader.registerBeanDefinitions(XmlBeanDefinitionReader.java:510)
at org.springframework.beans.factory.xml.XmlBeanDefinitionReader.doLoadBeanDefinitions(XmlBeanDefinitionReader.java:392)
... 27 more
五月 07, 2015 2:01:05 下午 org.apache.catalina.core.StandardContext startInternal
SEVERE: Error listenerStart
五月 07, 2015 2:01:05 下午 org.apache.catalina.core.StandardContext startInternal
SEVERE: Context [/graduate] startup failed due to previous errors
五月 07, 2015 2:01:05 下午 org.apache.catalina.core.ApplicationContext log
INFO: Closing Spring root WebApplicationContext
2015-05-07 14:01:05 INFO org.springframework.context.support.AbstractApplicationContext.doClose(862) | Closing Root WebApplicationContext: startup date [Thu May 07 14:01:05 CST 2015]; root of context hierarchy
2015-05-07 14:01:05 WARN org.springframework.context.support.AbstractApplicationContext.doClose(872) | Exception thrown from ApplicationListener handling ContextClosedEvent
java.lang.IllegalStateException: ApplicationEventMulticaster not initialized - call 'refresh' before multicasting events via the context: Root WebApplicationContext: startup date [Thu May 07 14:01:05 CST 2015]; root of context hierarchy
at org.springframework.context.support.AbstractApplicationContext.getApplicationEventMulticaster(AbstractApplicationContext.java:344)
at org.springframework.context.support.AbstractApplicationContext.publishEvent(AbstractApplicationContext.java:331)
at org.springframework.context.support.AbstractApplicationContext.doClose(AbstractApplicationContext.java:869)
at org.springframework.context.support.AbstractApplicationContext.close(AbstractApplicationContext.java:836)
at org.springframework.web.context.ContextLoader.closeWebApplicationContext(ContextLoader.java:579)
at org.springframework.web.context.ContextLoaderListener.contextDestroyed(ContextLoaderListener.java:115)
at org.apache.catalina.core.StandardContext.listenerStop(StandardContext.java:4831)
at org.apache.catalina.core.StandardContext.stopInternal(StandardContext.java:5478)
at org.apache.catalina.util.LifecycleBase.stop(LifecycleBase.java:232)
at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:160)
at org.apache.catalina.core.ContainerBase.addChildInternal(ContainerBase.java:901)
at org.apache.catalina.core.ContainerBase.addChild(ContainerBase.java:877)
at org.apache.catalina.core.StandardHost.addChild(StandardHost.java:618)
at org.apache.catalina.startup.HostConfig.deployDirectory(HostConfig.java:1100)
at org.apache.catalina.startup.HostConfig$DeployDirectory.run(HostConfig.java:1618)
at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:471)
at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:334)
at java.util.concurrent.FutureTask.run(FutureTask.java:166)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
at java.lang.Thread.run(Thread.java:724)
2015-05-07 14:01:05 WARN org.springframework.context.support.AbstractApplicationContext.doClose(880) | Exception thrown from LifecycleProcessor on context close
java.lang.IllegalStateException: LifecycleProcessor not initialized - call 'refresh' before invoking lifecycle methods via the context: Root WebApplicationContext: startup date [Thu May 07 14:01:05 CST 2015]; root of context hierarchy
at org.springframework.context.support.AbstractApplicationContext.getLifecycleProcessor(AbstractApplicationContext.java:357)
at org.springframework.context.support.AbstractApplicationContext.doClose(AbstractApplicationContext.java:877)
at org.springframework.context.support.AbstractApplicationContext.close(AbstractApplicationContext.java:836)
at org.springframework.web.context.ContextLoader.closeWebApplicationContext(ContextLoader.java:579)
at org.springframework.web.context.ContextLoaderListener.contextDestroyed(ContextLoaderListener.java:115)
at org.apache.catalina.core.StandardContext.listenerStop(StandardContext.java:4831)
at org.apache.catalina.core.StandardContext.stopInternal(StandardContext.java:5478)
at org.apache.catalina.util.LifecycleBase.stop(LifecycleBase.java:232)
at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:160)
at org.apache.catalina.core.ContainerBase.addChildInternal(ContainerBase.java:901)
at org.apache.catalina.core.ContainerBase.addChild(ContainerBase.java:877)
at org.apache.catalina.core.StandardHost.addChild(StandardHost.java:618)
at org.apache.catalina.startup.HostConfig.deployDirectory(HostConfig.java:1100)
at org.apache.catalina.startup.HostConfig$DeployDirectory.run(HostConfig.java:1618)
at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:471)
at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:334)
at java.util.concurrent.FutureTask.run(FutureTask.java:166)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
at java.lang.Thread.run(Thread.java:724)
五月 07, 2015 2:01:05 下午 org.apache.catalina.core.StandardContext listenerStop
SEVERE: Exception sending context destroyed event to listener instance of class org.springframework.web.context.ContextLoaderListener
java.lang.IllegalStateException: BeanFactory not initialized or already closed - call 'refresh' before accessing beans via the ApplicationContext
at org.springframework.context.support.AbstractRefreshableApplicationContext.getBeanFactory(AbstractRefreshableApplicationContext.java:170)
at org.springframework.context.support.AbstractApplicationContext.destroyBeans(AbstractApplicationContext.java:908)
at org.springframework.context.support.AbstractApplicationContext.doClose(AbstractApplicationContext.java:884)
at org.springframework.context.support.AbstractApplicationContext.close(AbstractApplicationContext.java:836)
at org.springframework.web.context.ContextLoader.closeWebApplicationContext(ContextLoader.java:579)
at org.springframework.web.context.ContextLoaderListener.contextDestroyed(ContextLoaderListener.java:115)
at org.apache.catalina.core.StandardContext.listenerStop(StandardContext.java:4831)
at org.apache.catalina.core.StandardContext.stopInternal(StandardContext.java:5478)
at org.apache.catalina.util.LifecycleBase.stop(LifecycleBase.java:232)
at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:160)
at org.apache.catalina.core.ContainerBase.addChildInternal(ContainerBase.java:901)
at org.apache.catalina.core.ContainerBase.addChild(ContainerBase.java:877)
at org.apache.catalina.core.StandardHost.addChild(StandardHost.java:618)
at org.apache.catalina.startup.HostConfig.deployDirectory(HostConfig.java:1100)
at org.apache.catalina.startup.HostConfig$DeployDirectory.run(HostConfig.java:1618)
at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:471)
at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:334)
at java.util.concurrent.FutureTask.run(FutureTask.java:166)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
at java.lang.Thread.run(Thread.java:724)
所以我只能不使用注解了。
事务一般是加到service层，这样可以统一管理。
<bean id="transactionManager" class="org.springframework.jdbc.datasource.DataSourceTransactionManager">
<property name="dataSource" ref="dataSource"></property>
</bean> <aop:config>
<aop:pointcut expression="execution(* com.wh.graduate.service.*.*(..))" id="serviceMethod" />
<aop:advisor advice-ref="txAdvice" pointcut-ref="serviceMethod"/>
</aop:config> <tx:advice id="txAdvice" transaction-manager="transactionManager">
<tx:attributes>
<tx:method name="*" propagation="REQUIRED"/></tx:attributes>
</tx:advice>
</beans>
（3）：有关事务的try{}catch(Exception e){}的注意点
如果你的dao层或者service进行了异常的捕获，那么你一定是需要抛出异常的。下面说明
A：如果你在dao层进行了异常的捕获，那么你需要把异常抛出，如下
try{
getSqlMapClientTemplate().insert("addOrder", Order);
}catch(Exception e){
throw new RuntimeException();
}
所以在这里有选择，要么别try，这样系统会自动捕;要try就需要抛出异常。对于service同理。
在调用处进行try，之后捕获到错误，返回相应的错误提醒
（4）：总结
快毕业了，我也出来一年了啊，2015年的5月4号，我出来整整一年啊，一年我变了很多，一年我也成长了很多，在这一年里面我学习到了很多东西，知识都是一点点积累的啊，但是因此，我越做越觉得自己是个码农，所以现在不知道是何去何从啊。我真的不想去做一个“为了敲代码而敲代码的人”。但是我现在就是码农，为了完成任务而完成任务，我想学的更多，更多底层的东西，但是框架的源码我自己看着好吃力啊，不过还是得坚持啊。最近准备学学c语言了，虽然以前学习过，但是那是四年前了，重新在学习一遍吧。知识永不止境啊。
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