Spring: bean conflict with existing non-compatible bean - spring

Question

Our project uses spring 2.5.5 and Tomcat. I have just migrated tomcat from 5.5 to 7. But when tomcat loads webapp context, we get this exception .
It seems spring scanned all the same components at least twice. Has anybody met this exception before?
Aug 16, 2012 1:54:36 PM org.apache.catalina.core.ApplicationContext log
INFO: Initializing Spring root WebApplicationContext
Aug 16, 2012 1:54:36 PM 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 class path resource [spring-configuration/application-context.xml]; nested exception is java.lang.IllegalStateException: Annotation-specified bean name 'observerLockMonitor' for bean class [aaa.aaa.ObserverLockMonitor] conflicts with existing, non-compatible bean definition of same name and class[aaa.aaa.ObserverLockMonitor]
at org.springframework.beans.factory.xml.XmlBeanDefinitionReader.doLoadBeanDefinitions(XmlBeanDefinitionReader.java:420)
at org.springframework.beans.factory.xml.XmlBeanDefinitionReader.loadBeanDefinitions(XmlBeanDefinitionReader.java:342)
at org.springframework.beans.factory.xml.XmlBeanDefinitionReader.loadBeanDefinitions(XmlBeanDefinitionReader.java:310)
at org.springframework.beans.factory.support.AbstractBeanDefinitionReader.loadBeanDefinitions(AbstractBeanDefinitionReader.java:143)
at org.springframework.beans.factory.support.AbstractBeanDefinitionReader.loadBeanDefinitions(AbstractBeanDefinitionReader.java:178)
at org.springframework.beans.factory.support.AbstractBeanDefinitionReader.loadBeanDefinitions(AbstractBeanDefinitionReader.java:149)
at org.springframework.web.context.support.XmlWebApplicationContext.loadBeanDefinitions(XmlWebApplicationContext.java:124)
at org.springframework.web.context.support.XmlWebApplicationContext.loadBeanDefinitions(XmlWebApplicationContext.java:92)
at org.springframework.context.support.AbstractRefreshableApplicationContext.refreshBeanFactory(AbstractRefreshableApplicationContext.java:123)
at org.springframework.context.support.AbstractApplicationContext.obtainFreshBeanFactory(AbstractApplicationContext.java:423)
at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:353)
at org.springframework.web.context.ContextLoader.createWebApplicationContext(ContextLoader.java:255)
at org.springframework.web.context.ContextLoader.initWebApplicationContext(ContextLoader.java:199)
at org.springframework.web.context.ContextLoaderListener.contextInitialized(ContextLoaderListener.java:45)
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.deployWAR(HostConfig.java:963)
at org.apache.catalina.startup.HostConfig$DeployWar.run(HostConfig.java:1600)
at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:441)
at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:303)
at java.util.concurrent.FutureTask.run(FutureTask.java:138)
at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:886)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:908)
at java.lang.Thread.run(Thread.java:662)
Caused by: java.lang.IllegalStateException: Annotation-specified bean name 'observerLockMonitor' for bean class [aaa.aaa.ObserverLockMonitor]conflicts with existing, non-compatible bean definition of same name and class [aaa.aaa.ObserverLockMonitor]
at org.springframework.context.annotation.ClassPathBeanDefinitionScanner.checkCandidate(ClassPathBeanDefinitionScanner.java:267)
at org.springframework.context.annotation.ClassPathBeanDefinitionScanner.doScan(ClassPathBeanDefinitionScanner.java:208)
at org.springframework.context.annotation.ComponentScanBeanDefinitionParser.parse(ComponentScanBeanDefinitionParser.java:85)
at org.springframework.beans.factory.xml.NamespaceHandlerSupport.parse(NamespaceHandlerSupport.java:69)
at org.springframework.beans.factory.xml.BeanDefinitionParserDelegate.parseCustomElement(BeanDefinitionParserDelegate.java:1255)
at org.springframework.beans.factory.xml.BeanDefinitionParserDelegate.parseCustomElement(BeanDefinitionParserDelegate.java:1245)
at org.springframework.beans.factory.xml.DefaultBeanDefinitionDocumentReader.parseBeanDefinitions(DefaultBeanDefinitionDocumentReader.java:135)
at org.springframework.beans.factory.xml.DefaultBeanDefinitionDocumentReader.registerBeanDefinitions(DefaultBeanDefinitionDocumentReader.java:92)
at org.springframework.beans.factory.xml.XmlBeanDefinitionReader.registerBeanDefinitions(XmlBeanDefinitionReader.java:507)
at org.springframework.beans.factory.xml.XmlBeanDefinitionReader.doLoadBeanDefinitions(XmlBeanDefinitionReader.java:398)
... 27 more
The web.xml under WEB-INF is:
<?xml version="1.0" encoding="UTF-8"?>
<web-app id="WebApp_ID" version="2.4"
xmlns="http://java.sun.com/xml/ns/j2ee"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://java.sun.com/xml/ns/j2ee http://java.sun.com/xml/ns/j2ee/web-app_2_4.xsd">
<context-param>
<param-name>contextConfigLocation</param-name>
<param-value>
classpath*:spring-configuration/*.xml;
classpath*:spring-configuration/${apollo.realm}/${apollo.domain}/*.xml;
classpath*:spring-configuration/${apollo.realm}/*.xml
</param-value>
</context-param>
<listener>
<listener-class>
org.springframework.web.context.ContextLoaderListener
</listener-class>
</listener>
<servlet>
<servlet-name>rds-eventProcessor</servlet-name>
<servlet-class>
org.springframework.web.servlet.DispatcherServlet
</servlet-class>
<load-on-startup>2</load-on-startup>
</servlet>
<servlet-mapping>
<servlet-name>rds-eventProcessor</servlet-name>
<url-pattern>/*</url-pattern>
</servlet-mapping>
<!--
<servlet>
<servlet-name>ping</servlet-name>
<servlet-class>
amazon.rds.processor.utils.VipHealthCheck
</servlet-class>
<load-on-startup>2</load-on-startup>
</servlet>
<servlet-mapping>
<servlet-name>ping</servlet-name>
<url-pattern>/ping/*</url-pattern>
</servlet-mapping>
-->
</web-app>
One of xml under classpath is application-context.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:context="http://www.springframework.org/schema/context"
xmlns:tx="http://www.springframework.org/schema/tx"
xmlns:p="http://www.springframework.org/schema/p"
xmlns:aop="http://www.springframework.org/schema/aop"
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/context
http://www.springframework.org/schema/context/spring-context-2.5.xsd
http://www.springframework.org/schema/tx
http://www.springframework.org/schema/tx/spring-tx-2.5.xsd "
default-destroy-method="shutdown">
<context:annotation-config />
<context:component-scan base-package="aaa.aaa" />
<context:component-scan base-package="bbb.bbb" />
<context:component-scan base-package="ccc.ccc" />
...... here we have some other beans that are defined manually.
</beans>
The beans definition is :
#Component
public class ObserverLockMonitor implements RDSAlfSessionDroppedListener {
public interface RDSAlfSessionStartedListener {
public void sessionStarted(AlfConnection alfConnection);
}
private static EventLog log = EventLogFactory.getEventLog(ObserverLockMonitor.class);
private final RDSAlfConnectionFactory alfConnectionFactory;
private final List<RDSAlfSessionStartedListener> sessionStartedListeners;
/**
* Timestamp of the last time we had a valid connection to alf...
*/
private Long timeOfLastSeenAlfConnection = System.currentTimeMillis();
private AlfConnection alfConnection;
#Autowired
public ObserverLockMonitor(RDSAlfConnectionFactory alfConnectionFactory, List<RDSAlfSessionStartedListener> sessionStartedListeners) {
this.alfConnectionFactory = alfConnectionFactory;
this.sessionStartedListeners = sessionStartedListeners;
}
Any hints or pointers would be appreciated.
Thanks.