java.lang.NoClassDefFoundError for interface of included project

[will zhang]

Dear all,
Here's my situation:

In project 1, I include project 2 in order to use interfaces (interface A, B, C, D.....) of project 2.
For one of the interfaces, A, the system always claim java.lang.NoClassDefFoundError while others are working fine.

If I move interface A from project 2 to project 1, it works.

I named interface A "User.java", is the name the reason which causes this problem, because in interceptor setting, I have <interceptor-stack name="user">. But after I change the name, still doesn't work.

Anyone can help? Thanks very much.

Error message:

SEVERE: Servlet.service() for servlet default threw exception
java.lang.NoClassDefFoundError: com/security/Person
	at java.lang.ClassLoader.defineClass1(Native Method)
	at java.lang.ClassLoader.defineClass(ClassLoader.java:620)
	at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:124)
	at org.apache.catalina.loader.WebappClassLoader.findClassInternal(WebappClassLoader.java:1847)
	at org.apache.catalina.loader.WebappClassLoader.findClass(WebappClassLoader.java:890)
	at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1354)
	at org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1233)
	at java.lang.ClassLoader.loadClassInternal(ClassLoader.java:319)
	at java.lang.Class.getDeclaredMethods0(Native Method)
	at java.lang.Class.privateGetDeclaredMethods(Class.java:2427)
	at java.lang.Class.getDeclaredMethods(Class.java:1791)
	at java.beans.Introspector$1.run(Introspector.java:1272)
	at java.security.AccessController.doPrivileged(Native Method)
	at java.beans.Introspector.getPublicDeclaredMethods(Introspector.java:1270)
	at java.beans.Introspector.getTargetMethodInfo(Introspector.java:1136)
	at java.beans.Introspector.getBeanInfo(Introspector.java:387)
	at java.beans.Introspector.getBeanInfo(Introspector.java:159)
	at java.beans.Introspector.getBeanInfo(Introspector.java:220)
	at java.beans.Introspector.<init>(Introspector.java:368)
	at java.beans.Introspector.getBeanInfo(Introspector.java:159)
	at org.springframework.beans.CachedIntrospectionResults.<init>(CachedIntrospectionResults.java:220)
	at org.springframework.beans.CachedIntrospectionResults.forClass(CachedIntrospectionResults.java:144)
	at org.springframework.beans.BeanWrapperImpl.getCachedIntrospectionResults(BeanWrapperImpl.java:252)
	at org.springframework.beans.BeanWrapperImpl.getPropertyDescriptors(BeanWrapperImpl.java:259)
	at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.unsatisfiedNonSimpleProperties(AbstractAutowireCapableBeanFactory.java:1108)
	at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.autowireByName(AbstractAutowireCapableBeanFactory.java:1023)
	at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.populateBean(AbstractAutowireCapableBeanFactory.java:975)
	at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.autowireBeanProperties(AbstractAutowireCapableBeanFactory.java:329)
	at com.opensymphony.xwork2.spring.SpringObjectFactory.autoWireBean(SpringObjectFactory.java:176)
	at com.opensymphony.xwork2.spring.SpringObjectFactory.buildBean(SpringObjectFactory.java:158)
	at com.opensymphony.xwork2.spring.SpringObjectFactory.buildBean(SpringObjectFactory.java:129)
	at com.opensymphony.xwork2.ObjectFactory.buildBean(ObjectFactory.java:139)
	at com.opensymphony.xwork2.ObjectFactory.buildAction(ObjectFactory.java:109)
	at com.opensymphony.xwork2.DefaultActionInvocation.createAction(DefaultActionInvocation.java:287)
	at com.opensymphony.xwork2.DefaultActionInvocation.init(DefaultActionInvocation.java:387)
	at com.opensymphony.xwork2.DefaultActionProxy.prepare(DefaultActionProxy.java:186)
	at org.apache.struts2.impl.StrutsActionProxy.prepare(StrutsActionProxy.java:61)
	at org.apache.struts2.impl.StrutsActionProxyFactory.createActionProxy(StrutsActionProxyFactory.java:39)
	at com.opensymphony.xwork2.DefaultActionProxyFactory.createActionProxy(DefaultActionProxyFactory.java:47)
	at org.apache.struts2.dispatcher.Dispatcher.serviceAction(Dispatcher.java:458)
	at org.apache.struts2.dispatcher.FilterDispatcher.doFilter(FilterDispatcher.java:395)
	at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
	at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
	at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:233)
	at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:191)
	at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:128)
	at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:102)
	at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109)
	at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:286)
	at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:845)
	at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:583)
	at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:447)
	at java.lang.Thread.run(Thread.java:619)
    

[Lorand Komaromi]

will zhang wrote:In project 1, I include project 2 in order to use interfaces

How do you "include" project 2? When deployed, are the required classes/interfaces in you web application's /WEB-INF/classes and jars in /WEB-INF/lib?

[will zhang]

Lorand Komaromi wrote:

will zhang wrote:In project 1, I include project 2 in order to use interfaces

How do you "include" project 2? When deployed, are the required classes/interfaces in you web application's /WEB-INF/classes and jars in /WEB-INF/lib?

I use eclipse to add project 2 to java build path of project 1. I used this method many times to include another project, it works fine.

[will zhang]

I export project 2 as a JAR and the result is the same.

[Lorand Komaromi]

will zhang wrote:I export project 2 as a JAR and the result is the same.

Did you add the jar to WEB-INF/lib..?

[will zhang]

Lorand Komaromi wrote:

will zhang wrote:I export project 2 as a JAR and the result is the same.

Did you add the jar to WEB-INF/lib..?

Adding the jar into WEB-INF/lib solved the problem. Thanks!

I wonder what's the difference between putting jar in build path and putting jar in WEB-INF/lib. Appreciate!

[Lorand Komaromi]

will zhang wrote:I wonder what's the difference between putting jar in build path and putting jar in WEB-INF/lib. Appreciate!

If it's in the build path, Eclipse will be able to compile the project and offer its classes when you hit Ctrl+space, but if it's not in the right folder, it won't be found when your application is deployed. The latest Eclipse automatically adds the jars from WEB-INF/lib to your project's build path!