how to solve this error???

By: dharmb*** On: Fri Jul 08 15:18:21 IST 2016     0 0 0	0
HTTP Status 500 - java.lang.reflect.InvocationTargetException type Exception report message java.lang.reflect.InvocationTargetException description The server encountered an internal error that prevented it from fulfilling this request. exception javax.servlet.ServletException: java.lang.reflect.InvocationTargetException org.apache.struts2.dispatcher.Dispatcher.serviceAction(Dispatcher.java:515) org.apache.struts2.dispatcher.FilterDispatcher.doFilter(FilterDispatcher.java:419) root cause java.lang.reflect.InvocationTargetException sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source) sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source) java.lang.reflect.Method.invoke(Unknown Source) com.opensymphony.xwork2.DefaultActionInvocation.invokeAction(DefaultActionInvocation.java:404) com.opensymphony.xwork2.DefaultActionInvocation.invokeActionOnly(DefaultActionInvocation.java:267) com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:229) com.opensymphony.xwork2.interceptor.DefaultWorkflowInterceptor.doIntercept(DefaultWorkflowInterceptor.java:221) com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:86) com.opensymphony.xwork2.DefaultActionInvocation$2.doProfiling(DefaultActionInvocation.java:224) com.opensymphony.xwork2.DefaultActionInvocation$2.doProfiling(DefaultActionInvocation.java:223) com.opensymphony.xwork2.util.profiling.UtilTimerStack.profile(UtilTimerStack.java:455) com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:221) com.opensymphony.xwork2.validator.ValidationInterceptor.doIntercept(ValidationInterceptor.java:150) org.apache.struts2.interceptor.validation.AnnotationValidationInterceptor.doIntercept(AnnotationValidationInterceptor.java:48) com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:86) com.opensymphony.xwork2.DefaultActionInvocation$2.doProfiling(DefaultActionInvocation.java:224) com.opensymphony.xwork2.DefaultActionInvocation$2.doProfiling(DefaultActionInvocation.java:223) com.opensymphony.xwork2.util.profiling.UtilTimerStack.profile(UtilTimerStack.java:455) com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:221) com.opensymphony.xwork2.interceptor.ConversionErrorInterceptor.intercept(ConversionErrorInterceptor.java:123) com.opensymphony.xwork2.DefaultActionInvocation$2.doProfiling(DefaultActionInvocation.java:224) com.opensymphony.xwork2.DefaultActionInvocation$2.doProfiling(DefaultActionInvocation.java:223) com.opensymphony.xwork2.util.profiling.UtilTimerStack.profile(UtilTimerStack.java:455) com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:221) com.opensymphony.xwork2.interceptor.ParametersInterceptor.doIntercept(ParametersInterceptor.java:167) com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:86) com.opensymphony.xwork2.DefaultActionInvocation$2.doProfiling(DefaultActionInvocation.java:224) com.opensymphony.xwork2.DefaultActionInvocation$2.doProfiling(DefaultActionInvocation.java:223) com.opensymphony.xwork2.util.profiling.UtilTimerStack.profile(UtilTimerStack.java:455) com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:221) com.opensymphony.xwork2.interceptor.StaticParametersInterceptor.intercept(StaticParametersInterceptor.java:105) com.opensymphony.xwork2.DefaultActionInvocation$2.doProfiling(DefaultActionInvocation.java:224) com.opensymphony.xwork2.DefaultActionInvocation$2.doProfiling(DefaultActionInvocation.java:223) com.opensymphony.xwork2.util.profiling.UtilTimerStack.profile(UtilTimerStack.java:455) com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:221) org.apache.struts2.interceptor.CheckboxInterceptor.intercept(CheckboxInterceptor.java:83) com.opensymphony.xwork2.DefaultActionInvocation$2.doProfiling(DefaultActionInvocation.java:224) com.opensymphony.xwork2.DefaultActionInvocation$2.doProfiling(DefaultActionInvocation.java:223) com.opensymphony.xwork2.util.profiling.UtilTimerStack.profile(UtilTimerStack.java:455) com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:221) org.apache.struts2.interceptor.FileUploadInterceptor.intercept(FileUploadInterceptor.java:207) com.opensymphony.xwork2.DefaultActionInvocation$2.doProfiling(DefaultActionInvocation.java:224) com.opensymphony.xwork2.DefaultActionInvocation$2.doProfiling(DefaultActionInvocation.java:223) com.opensymphony.xwork2.util.profiling	0