Eclipse用表单form上传出现报错

为什么这个request接收一直报错啊？

-List<FileItem> list=servletFileUpload.parseRequest(request);

报错显示的是：

The type javax.servlet.http.HttpServletRequest cannot be resolved. It is indirectly
referenced from required .class files
- The method parseRequest(HttpServletRequest) from the type ServletFileUpload refers
to the missing type HttpServletRequest

用eclipse搞了半天也不行，同学用idea就没问题。。

入参request对象没创建，语法错误