Q:

NoClassDefFoundError: Can't instantiate class on application server, works fine locally

I have an ear running on WebLogic that contains an ejb. All runs well until the ejb tries to instantiate an object of ServiceFactory - one of our own classes.
In my unit tests, I could create an object of the class locally. It's on the server that the error occurs.
I'm guessing this is either a build/packaging issue or a WebLogic 10.3.6 quirk but don't know where to proceed from here given that the dependency exists in the ear (in APP-INF/lib). I've also tried moving the dependency that contains the class to the root of the ear. "Class-Path: " is blank in the MANIFEST.MF file for the ejb and the ear, but the product has run fine until now without them. I'm building with Maven.
javax.ejb.EJBException: what do i do: seems an odd quirk of the EJB spec.  The exception is:java.lang.NoClassDefFoundError: Could not initialize class com.company.ts.management.icm.service.ServiceFactory
at com.oracle.pitchfork.intercept.MethodInvocationInvocationContext.proceed(MethodInvocationInvocationContext.java:110)
at com.company.it.techservices.aae.service.CommonService.bizLog(CommonService.java:37)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:601)
at com.bea.core.repackaged.springframework.aop.support.AopUtils.invokeJoinpointUsingReflection(AopUtils.java:310)
at com.oracle.pitchfork.intercept.JeeInterceptorInterceptor.invoke(JeeInterceptorInterceptor.java:68)
at com.bea.core.repackaged.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:171)
at com.bea.core.repackaged.springframework.aop.support.DelegatingIntroductionInterceptor.doProceed(DelegatingIntroductionInterceptor.java:131)
at com.bea.core.repackaged.springframework.aop.support.DelegatingIntroductionInterceptor.invoke(DelegatingIntroductionInterceptor.java:119)
at com.bea.core.repackaged.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:171)
at com.oracle.pitchfork.spi.MethodInvocationVisitorImpl.visit(MethodInvocationVisitorImpl.java:34)
at weblogic.ejb.container.injection.EnvironmentInterceptorCallbackImpl.callback(EnvironmentInterceptorCallbackImpl.java:54)
at com.oracle.pitchfork.spi.EnvironmentInterceptor.invoke(EnvironmentInterceptor.java:42)
at com.bea.core.repackaged.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:171)
at com.bea.core.repackaged.springframework.aop.interceptor.ExposeInvocationInterceptor.invoke(ExposeInvocationInterceptor.java:89)
at com.bea.core.repackaged.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:171)
at com.bea.core.repackaged.springframework.aop.support.DelegatingIntroductionInterceptor.doProceed(DelegatingIntroductionInterceptor.java:131)
at com.bea.core.repackaged.springframework.aop.support.DelegatingIntroductionInterceptor.invoke(DelegatingIntroductionInterceptor.java:119)
at com.bea.core.repackaged.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:171)
at com.bea.core.repackaged.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAopProxy.java:204)
at com.sun.proxy.$Proxy476.calculateRoles(Unknown Source)
at com.company.it.techservices.aae.autheng.AuthorizationEngineBean_t79b4w_AuthorizationEngineBeanRemoteImpl.__WL_invoke(Unknown Source)
at weblogic.ejb.container.internal.SessionRemoteMethodInvoker.invoke(SessionRemoteMethodInvoker.java:40)
at com.company.it.techservices.aae.autheng.AuthorizationEngineBean_t79b4w_AuthorizationEngineBeanRemoteImpl.calculateRoles(Unknown Source)
at com.company.it.techservices.aae.autheng.AuthorizationEngineBean_t79b4w_AuthorizationEngineBeanRemoteImpl_WLSkel.invoke(Unknown Source)
at weblogic.rmi.internal.BasicServerRef.invoke(BasicServerRef.java:667)
at weblogic.rmi.cluster.ClusterableServerRef.invoke(ClusterableServerRef.java:230)
at weblogic.rmi.internal.BasicServerRef$1.run(BasicServerRef.java:522)
at weblogic.security.acl.internal.AuthenticatedSubject.doAs(AuthenticatedSubject.java:363)
at weblogic.security.service.SecurityManager.runAs(SecurityManager.java:146)
at weblogic.rmi.internal.BasicServerRef.handleRequest(BasicServerRef.java:518)
at weblogic.rmi.internal.wls.WLSExecuteRequest.run(WLSExecuteRequest.java:118)
at weblogic.work.ExecuteThread.execute(ExecuteThread.java:256)
at weblogic.work.ExecuteThread.run(ExecuteThread.java:221)

A:

In general NoClassDefFoundError means the class was probably found but could not initialize. So something in the code for that class throws an error when it is instantiated (it could mean a different class entirely is missing). 
Check the code for your class. Specifically look for static blocks or members which use a class that's not found by the ClassLoader.

