I have two public classes configured as follows in the context of a Spring application:
public class LoadErrorData{
private ExceptionData exceptionData;
public LoadErrorData() { }
}
public class ExceptionData implements Serializable{
private Resource exceptionDataResource;
public ExceptionData() { }
}
Spring applicationContext.xml:
<beans:bean id="loadErrorData" class="com.startup.LoadErrorData" init-method="startup">
<beans:property name="exceptionData" ref="exceptionData"/>
</beans:bean>
<beans:bean id="exceptionData" class="com.server.ExceptionData" init-method="startup">
<beans:property name="exceptionDataResource" value="classpath:${exception.datafile.path}"/>
</beans:bean>
It gives the following exception during initialization:
Oct 07, 2013 1:45:21 PM org.apache.catalina.core.StandardContext listenerStart SEVERE: org.springframework.web.context.ContextLoaderListener org.springframework.beans.factory.BeanCreationException: bean "loadErrorData", [spring/startup-config.xml]: bean ; org.springframework.beans.ConversionNotSupportedException: com.sun.proxy. $Proxy12 java.io.Serializable, org.springframework.aop.SpringProxy, org.springframework.aop.framework.Advised " 'com.server.IICExceptionData' 'ExceptionData'; : java.lang.IllegalStateException: [com.sun.proxy. $Proxy12 java.io.Serializable, org.springframework.aop.SpringProxy, org.springframework.aop.framework.Advised] [com.server.IICExceptionData] 'exceptionData': , org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:527) org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:456) org.springframework.beans.factory.support.AbstractBeanFactory $1.getObject(AbstractBeanFactory.java:294) org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:225) org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:291) org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:193) org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:609) org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:918) org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:469) org.springframework.web.context.ContextLoader.configureAndRefreshWebApplicationContext(ContextLoader.java:383) org.springframework.web.context.ContextLoader.initWebApplicationContext(ContextLoader.java:283) org.springframework.web.context.ContextLoaderListener.contextInitialized(ContextLoaderListener.java:111) org.apache.catalina.core.StandardContext.listenerStart(StandardContext.java:4723) org.apache.catalina.core.StandardContext $1.call(StandardContext.java:5226) org.apache.catalina.core.StandardContext $1.call(StandardContext.java:5221) java.util.concurrent.FutureTask $Sync.innerRun(FutureTask.java:334) java.util.concurrent.FutureTask.run(FutureTask.java:166) java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145) java.util.concurrent.ThreadPoolExecutor $Worker.run(ThreadPoolExecutor.java:615) java.lang.Thread.run(Thread.java:724) : org.springframework.beans.ConversionNotSupportedException: com.sun.proxy. $Proxy12 java.io.Serializable, org.springframework.aop.SpringProxy, org.springframework.aop.framework.Advised" 'com.server.IICExceptionData' 'ExceptionData'; : java.lang.IllegalStateException: [com.sun.proxy. $Proxy12 java.io.Serializable, org.springframework.aop.SpringProxy, org.springframework.aop.framework.Advised] [com.server.IICExceptionData] 'exceptionData': , org.springframework.beans.BeanWrapperImpl.convertIfNecessary(BeanWrapperImpl.java:485) org.springframework.beans.BeanWrapperImpl.convertForProperty(BeanWrapperImpl.java:516) org.springframework.beans.BeanWrapperImpl.convertForProperty(BeanWrapperImpl.java:510) org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.convertForProperty(AbstractAutowireCapableBeanFactory.java:1406) org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.applyPropertyValues (AbstractAutowireCapableBeanFactory.java:1365) org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.populateBean(AbstractAutowireCapableBeanFactory.java:1118) org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:517)... 19 more : java.lang.IllegalStateException: [com.sun.proxy. $Proxy12 java.io.Serializable, org.springframework.aop.SpringProxy, org.springframework.aop.framework.Advised] [com.server.IICExceptionData] 'exceptionData': , org.springframework.beans.TypeConverterDelegate.convertIfNecessary(TypeConverterDelegate.java:241) org.springframework.beans.BeanWrapperImpl.convertIfNecessary(BeanWrapperImpl.java:470)... 25
but when I put
<aop:scoped-proxy proxy-target-class="true"/>
in ExceptionDatabean configuration OR if i remove
implements Serializable
of ExceptionData
The exception is. My point point AOP is as follows:
expression="execution(* com..*(..))"
It looks like Spring is trying to create a CGLIB proxy for the bean LoadErrorData (since it does not implement any interface) and JDKdynamicProxy for its ExceptionData dependency (since it implements the Serializable interface) . And he cannot do that. Because when I tell Spring to create a CGLIB proxy explicitly for ExceptionData, it works fine. Why is this so? Why can't he create a JDKDynamic Proxy for a bean (ExceptionData), which is a dependency of a bean (LoadErrorData), for which he is trying to create a CGLIB proxy? According to the documentation, this suggests that Spring will detect this automatically.