前端使用element ui  el-upload，上传图片文件时，调用getfile方法报错，百度了一下没搜到相关问题

java.lang.IllegalStateException: READER

at org.eclipse.jetty.server.Request.getInputStream(Request.java:596)

at com.oreilly.servlet.multipart.MultipartParser.<init>(MultipartParser.java:185)

at com.oreilly.servlet.MultipartRequest.<init>(MultipartRequest.java:223)

at com.jfinal.upload.MultipartRequest.wrapMultipartRequest(MultipartRequest.java:107)

at com.jfinal.upload.MultipartRequest.<init>(MultipartRequest.java:68)

at com.jfinal.core.Controller.getFiles(Controller.java:815)

at com.jfinal.core.Controller.getFile(Controller.java:820)

at com.jkrcw.admin.common.controller.IndexController.upload(IndexController.java:23)

at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)

at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)

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

at java.lang.reflect.Method.invoke(Method.java:498)

at com.jfinal.aop.Invocation.invoke(Invocation.java:73)

at com.jkrcw.common.interceptor.CrossDomainInterceptor.intercept(CrossDomainInterceptor.java:32)

at com.jfinal.aop.Invocation.invoke(Invocation.java:67)

at com.jfinal.ext.interceptor.SessionInViewInterceptor.intercept(SessionInViewInterceptor.java:44)