MultipartFile sumario is null | Spring MVC I: Criando aplicações web

o file sempre chega null no post
segue codigo
@RequestMapping(method=RequestMethod.POST)
    public ModelAndView grava(MultipartFile sumario, @Valid Produto produto, BindingResult result, RedirectAttributes redirectAttributes){




        if(result.hasErrors()){
            return  form(produto);
        }

        produto.setSumarioPath(fileSaver.write("arquivo-sumario", sumario));

        produtoDAO.gravar(produto);
        redirectAttributes.addFlashAttribute("sucesso","Producto cadastrado com sucesso");
        ModelAndView modelAndView = new ModelAndView("redirect:produtos");

        return modelAndView;


    }



@Bean
    public MultipartResolver multipartResolver(){
        return new StandardServletMultipartResolver();

    }




<%@ page language="java" contentType="text/html; charset=UTF-8"
    pageEncoding="UTF-8"%>
    <%@ tagliburi="http://java.sun.com/jsp/jstl/core" prefix="c" %>
    <%@ tagliburi="http://www.springframework.org/tags/form" prefix="form" %>
    <%@ tagliburi="http://www.springframework.org/tags" prefix="s" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>Livros...</title>
</head>
<body>
    <form:form action="${s:mvcUrl('PC#grava').build() }" method="post" commandName="produto"  enctype="multipart/form-data">

        <div>
            <label>Titulo</label>
             <form:input path="titulo" />
            <form:errors path="titulo"></form:errors>

        </div>
        <div>
            <label>Descricao</label>
            <form:textarea path="descricao" rows="10" cols="20" /></textarea>
            <form:errors path="descricao"></form:errors>
        </div>
         <div>
            <label>Data Lançamento</label>
            <form:input path="dataLancamento" />
            <form:errors path="dataLancamento"></form:errors>
        </div>


        <div>
            <label>Paginas</label>
            <form:input path="paginas" />
            <form:errors path="paginas"></form:errors>
        </div>
        <c:forEach items="${tipos}" var="tipoPreco" varStatus="status">
        <div>
            <label>${tipoPreco}</label> 
            <form:input path="precos[${status.index}].valor"/>
             <form:hidden path="precos[${status.index}].tipo" value="${tipoPreco}"/>
        </div>
        </c:forEach>


        <div>
            <label>Sumario</label>
            <input type="file" path="sumario" />

        </div>

        <button type="submit">Cadastrar</button>
    </form:form>
</body>
</html>




@Override
    protected Class<?>[] getServletConfigClasses() {
        // TODO Auto-generated method stub
        return new Class[]{AppWebConfiguration.class, JPAConfiguration.class, FileSaver.class};
    }



package br.com.casadocodigo.loja.infra;

import java.io.File;
import java.io.IOException;

import javax.servlet.http.HttpServletRequest;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Component;
import org.springframework.web.multipart.MultipartFile;

@Component
public class FileSaver {


    @Autowired
    private HttpServletRequest request;

    public String write(String basePath, MultipartFile file){

        try {

             String realPath = request.getServletContext().getRealPath("/"+basePath);         
             String path = realPath+"/"+file.getOriginalFilename();
             file.transferTo(new File(path));
             return basePath+"/"+file.getOriginalFilename();
        } catch (IllegalStateException | IOException e) {
            // TODO Auto-generated catch block
        throw new RuntimeException();
        }



    }

}
Mergulhe em programação
