com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:248)

com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:248)

com.opensymphony.xwork2.DefaultActionInvocation.invoke(DefaultActionInvocation.java:248)

sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)

com.opensymphony.xwork2.interceptor.StaticParametersInterceptor.intercept(StaticParametersInterceptor.java:190)

com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:98)

com.opensymphony.xwork2.interceptor.MethodFilterInterceptor.intercept(MethodFilterInterceptor.java:98)

org.apache.struts2.interceptor.FileUploadInterceptor.intercept(FileUploadInterceptor.java:243)

com.alibaba.fastjson.serializer.MapSerializer.write(MapSerializer.java:188)

com.alibaba.fastjson.JSON.toJSONString(JSON.java:406)