求助，DWZ的上传问题，怎么老是报错呀！：报错

org.apache.commons.fileupload.FileUploadBase$InvalidContentTypeException: the request doesn't contain a multipart/form-data or multipart/mixed stream, content type header is application/x-www-form-urlencoded; charset=UTF-8 at org.apache.commons.fileupload.FileUploadBase$FileItemIteratorImpl.(FileUploadBase.java:947) at org.apache.commons.fileupload.FileUploadBase.getItemIterator(FileUploadBase.java:310) at org.apache.commons.fileupload.FileUploadBase.parseRequest(FileUploadBase.java:334) at org.apache.commons.fileupload.servlet.ServletFileUpload.parseRequest(ServletFileUpload.java:115) at com.dxcm.controller.ActivesController.edit(ActivesController.java:148) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25) at java.lang.reflect.Method.invoke(Method.java:597) at com.jfinal.core.ActionInvocation.invoke(ActionInvocation.java:55) at com.dxcm.interceptor.LoginCheckInterceptor.intercept(LoginCheckInterceptor.java:12) at com.jfinal.core.ActionInvocation.invoke(ActionInvocation.java:51) at com.dxcm.interceptor.CheckTokenInterceptor.intercept(CheckTokenInterceptor.java:11) at com.jfinal.core.ActionInvocation.invoke(ActionInvocation.java:51) at com.dxcm.interceptor.GlobalInterceptor.intercept(GlobalInterceptor.java:21) at com.jfinal.core.ActionInvocation.invoke(ActionInvocation.java:51) at com.jfinal.ext.interceptor.SessionInViewInterceptor.intercept(SessionInViewInterceptor.java:44) at com.jfinal.core.ActionInvocation.invoke(ActionInvocation.java:51) at com.jfinal.core.ActionHandler.handle(ActionHandler.java:73) at com.jfinal.core.JFinalFilter.doFilter(JFinalFilter.java:72) 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)