今天在spring中使用事务时，遇到了这个问题，已启动tomcat就出错：

org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'diseasesQueryControl': Injection of autowired dependencies failed; nested exception is org.springframework.beans.factory.BeanCreationException: Could not autowire field: private org.ccnt.med.abservice.QueryService org.ccnt.med.control.DiseasesQueryControl.queryService; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'queryServiceImpl': Injection of autowired dependencies failed; nested exception is org.springframework.beans.factory.BeanCreationException: Could not autowire field: private org.ccnt.med.dao.TbDiseaseDao org.ccnt.med.servimpl.QueryServiceImpl.tbDiseaseDao; nested exception is java.lang.IllegalArgumentException: Can not set org.ccnt.med.dao.TbDiseaseDao field org.ccnt.med.servimpl.QueryServiceImpl.tbDiseaseDao to $Proxy9    at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor.postProcessPropertyValues(AutowiredAnnotationBeanPostProcessor.java:285)    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.populateBean(AbstractAutowireCapableBeanFactory.java:1074)    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:517)    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:456)    at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:291)    at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:222)    at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:288)    at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:190)    at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:580)    at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:895)    at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:425)    at org.springframework.web.context.ContextLoader.createWebApplicationContext(ContextLoader.java:276)    at org.springframework.web.context.ContextLoader.initWebApplicationContext(ContextLoader.java:197)    at org.springframework.web.context.ContextLoaderListener.contextInitialized(ContextLoaderListener.java:47)    at org.apache.catalina.core.StandardContext.listenerStart(StandardContext.java:4791)    at org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:5285)    at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:150)    at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1559)    at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1549)    at java.util.concurrent.FutureTask$Sync.innerRun(Unknown Source)    at java.util.concurrent.FutureTask.run(Unknown Source)    at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(Unknown Source)    at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)    at java.lang.Thread.run(Unknown Source)

解决方法：

在配置文件中加入proxy-target-class="true"

或者：

现在我的配置文件如下：

解释：

AOP使用的动态代理可以针对接口，也可以针对类。java的动态代理只能针对接口。

在用Spring的AOP时，默认动态代理是针对接口的，而我用的是针对类的，所以要加上proxy-target-class="true"