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堆栈信息:
java.lang.NullPointerException at com.dimensions.action.common.ProductGuessingAction.index(ProductGuessingAction.java:51) at com.dimensions.action.common.ProductGuessingAction$$EnhancerByGuice$$d06b19ca.CGLIB$index$3(<generated>) at com.dimensions.action.common.ProductGuessingAction$$EnhancerByGuice$$d06b19ca$$FastClassByGuice$$de07a14f.invoke(<generated>) at com.google.inject.internal.cglib.proxy.MethodProxy.invokeSuper(MethodProxy.java:228) at com.google.inject.InterceptorStackCallback$InterceptedMethodInvocation.proceed(InterceptorStackCallback.java:64) at com.dimensions.core.db.DBInterceptor.invoke(DBInterceptor.java:14) at com.google.inject.InterceptorStackCallback$InterceptedMethodInvocation.proceed(InterceptorStackCallback.java:64) at com.google.inject.InterceptorStackCallback.intercept(InterceptorStackCallback.java:44) at com.dimensions.action.common.ProductGuessingAction$$EnhancerByGuice$$d06b19ca.index(<generated>) at sun.reflect.GeneratedMethodAccessor885.invoke(Unknown Source) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) at java.lang.reflect.Method.invoke(Method.java:498) at ognl.OgnlRuntime.invokeMethod(OgnlRuntime.java:892) at ognl.OgnlRuntime.callAppropriateMethod(OgnlRuntime.java:1294) at ognl.ObjectMethodAccessor.callMethod(ObjectMethodAccessor.java:68) at com.opensymphony.xwork2.ognl.accessor.XWorkMethodAccessor.callMethodWithDebugInfo(XWorkMethodAccessor.java:117) at com.opensymphony.xwork2.ognl.accessor.XWorkMethodAccessor.callMethod(XWorkMethodAccessor.java:108) at ognl.OgnlRuntime.callMethod(OgnlRuntime.java:1370) at ognl.ASTMethod.getValueBody(ASTMethod.java:91) at ognl.SimpleNode.evaluateGetValueBody(SimpleNode.java:212) at ognl.SimpleNode.getValue(SimpleNode.java:258) at ognl.Ognl.getValue(Ognl.java:467) at ognl.Ognl.getValue(Ognl.java:431) at com.opensymphony.xwork2.ognl.OgnlUtil$3.execute(OgnlUtil.java:352) at com.opensymphony.xwork2.ognl.OgnlUtil.compileAndExecuteMethod(OgnlUtil.java:404) at com.opensymphony.xwork2.ognl.OgnlUtil.callMethod(OgnlUtil.java:350) at com.opensymphony.xwork2.DefaultActionInvocation.invokeAction(DefaultActionInvocation.java:430) at com.opensymphony.xwork2.DefaultActionInvocation.invokeActionOnly(DefaultActionInvocation.java:290) at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:251) at com.dimensions.interceptor.RequestLogInterceptor.intercept(RequestLogInterceptor.java:63) at com.dimensions.core.GuiceObjectFactory$ProvidedInterceptor.intercept(GuiceObjectFactory.java:226) at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:245) at com.opensymphony.xwork2.interceptor.DefaultWorkflowInterceptor.doIntercept(DefaultWorkflowInterceptor.java:168) at com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:98) at com.dimensions.core.GuiceObjectFactory$ProvidedInterceptor.intercept(GuiceObjectFactory.java:226) at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:245) at com.opensymphony.xwork2.validator.ValidationInterceptor.doIntercept(ValidationInterceptor.java:265) at org.apache.struts2.interceptor.validation.AnnotationValidationInterceptor.doIntercept(AnnotationValidationInterceptor.java:76) at com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:98) at com.dimensions.core.GuiceObjectFactory$ProvidedInterceptor.intercept(GuiceObjectFactory.java:226) at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:245) at com.opensymphony.xwork2.interceptor.ConversionErrorInterceptor.intercept(ConversionErrorInterceptor.java:138) at com.dimensions.core.GuiceObjectFactory$ProvidedInterceptor.intercept(GuiceObjectFactory.java:226) at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:245) at com.opensymphony.xwork2.interceptor.ParametersInterceptor.doIntercept(ParametersInterceptor.java:229) at com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:98) at com.dimensions.core.GuiceObjectFactory$ProvidedInterceptor.intercept(GuiceObjectFactory.java:226) at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:245) at com.opensymphony.xwork2.interceptor.ParametersInterceptor.doIntercept(ParametersInterceptor.java:229) at com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:98) at com.dimensions.core.GuiceObjectFactory$ProvidedInterceptor.intercept(GuiceObjectFactory.java:226) at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:245) at com.opensymphony.xwork2.interceptor.StaticParametersInterceptor.intercept(StaticParametersInterceptor.java:191) at com.dimensions.core.GuiceObjectFactory$ProvidedInterceptor.intercept(GuiceObjectFactory.java:226) at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:245) at org.apache.struts2.interceptor.FileUploadInterceptor.intercept(FileUploadInterceptor.java:253) at com.dimensions.core.GuiceObjectFactory$ProvidedInterceptor.intercept(GuiceObjectFactory.java:226) at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:245) at com.opensymphony.xwork2.interceptor.ModelDrivenInterceptor.intercept(ModelDrivenInterceptor.java:100) at com.dimensions.core.GuiceObjectFactory$ProvidedInterceptor.intercept(GuiceObjectFactory.java:226) at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:245) at com.opensymphony.xwork2.interceptor.PrepareInterceptor.doIntercept(PrepareInterceptor.java:171) at com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:98) at com.dimensions.core.GuiceObjectFactory$ProvidedInterceptor.intercept(GuiceObjectFactory.java:226) at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:245) at org.apache.struts2.interceptor.ServletConfigInterceptor.intercept(ServletConfigInterceptor.java:164) at com.dimensions.core.GuiceObjectFactory$ProvidedInterceptor.intercept(GuiceObjectFactory.java:226) at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:245) at com.opensymphony.xwork2.interceptor.ParametersInterceptor.doIntercept(ParametersInterceptor.java:229) at com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:98) at com.dimensions.core.GuiceObjectFactory$ProvidedInterceptor.intercept(GuiceObjectFactory.java:226) at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:245) at org.apache.struts2.interceptor.MultiselectInterceptor.intercept(MultiselectInterceptor.java:73) at com.dimensions.core.GuiceObjectFactory$ProvidedInterceptor.intercept(GuiceObjectFactory.java:226) at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:245) at org.apache.struts2.interceptor.DateTextFieldInterceptor.intercept(DateTextFieldInterceptor.java:125) at com.dimensions.core.GuiceObjectFactory$ProvidedInterceptor.intercept(GuiceObjectFactory.java:226) at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:245) at com.opensymphony.xwork2.interceptor.I18nInterceptor.intercept(I18nInterceptor.java:140) at com.dimensions.core.GuiceObjectFactory$ProvidedInterceptor.intercept(GuiceObjectFactory.java:226) at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:245) at com.opensymphony.xwork2.interceptor.ExceptionMappingInterceptor.intercept(ExceptionMappingInterceptor.java:189) at com.dimensions.core.GuiceObjectFactory$ProvidedInterceptor.intercept(GuiceObjectFactory.java:226) at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:245) at com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:100) at com.dimensions.core.GuiceObjectFactory$ProvidedInterceptor.intercept(GuiceObjectFactory.java:226) at com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:245) at org.apache.struts2.impl.StrutsActionProxy.execute(StrutsActionProxy.java:54) at org.apache.struts2.dispatcher.Dispatcher.serviceAction(Dispatcher.java:575) at org.apache.struts2.dispatcher.ng.ExecuteOperations.executeAction(ExecuteOperations.java:81) at org.apache.struts2.dispatcher.ng.filter.StrutsPrepareAndExecuteFilter.doFilter(StrutsPrepareAndExecuteFilter.java:99) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:241) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208) at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:219) at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:110) at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:492) at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:165) at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:104) at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:116) at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:452) at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1195) at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:654) at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:317) at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149) at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624) at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61) at java.lang.Thread.run(Thread.java:748)

异常信息：：

java.lang.NullPointerException