SpringMvc4.x高级配置(一):文件上传配置

一. 点睛

文件上传是一个项目里经常要用到的功能，Spring MVC通过配置一个MultipartResolver来上传文件。

在Spring的控制器中，通过MultipartFile file来接收文件，通过MultipartFile[] files接收多个文件上传。

二. 示例

1. 添加文件上传依赖

<!-- file upload -->
<dependency>
    <groupId>commons-fileupload</groupId>
    <artifactId>commons-fileupload</artifactId>
    <version>1.3.1</version>
</dependency>
<!-- 非必需，可简化IO操作 -->
<dependency>
    <groupId>commons-io</groupId>
    <artifactId>commons-io</artifactId>
    <version>2.3</version>
</dependency>

2. 增加上传页面upload.jsp。

在src/main/resources/views下新建upload.jsp


<%@ page language="java" contentType="text/html; charset=UTF-8"
    pageEncoding="UTF-8"%>
<!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>upload page</title>

</head>
<body>

<div class="upload">
    <form action="upload" enctype="multipart/form-data" method="post">
        <input type="file" name="file"/><br/>
        <input type="submit" value="上传">
    </form>
</div>


</body>
</html>

3. 添加转向到upload页面的ViewController

在文件MyMvcConfig的addViewControllers方法里面增加下面的转向配置，代码如下:

registry.addViewController("/toUpload").setViewName("/upload");

添加完成之后的代码如下所示：


@Override
public void addViewControllers(ViewControllerRegistry registry) {
    registry.addViewController("/index").setViewName("/index");
    registry.addViewController("/toUpload").setViewName("/upload");
}

4. MultipartResolver配置

在文件MyMvcConfig中增加下面的代码，提供对上传文件的支持：

@Bean
public MultipartResolver multipartResolver() {
    CommonsMultipartResolver multipartResolver = new CommonsMultipartResolver();
    multipartResolver.setMaxUploadSize(1000000);
    return multipartResolver;
}

5. 控制器

package org.light4j.springMvc4.web;

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

import org.apache.commons.io.FileUtils;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.bind.annotation.ResponseBody;
import org.springframework.web.multipart.MultipartFile;

@Controller
public class UploadController {

    @RequestMapping(value = "/upload", method = RequestMethod.POST)
    public @ResponseBody
    String upload(MultipartFile file) {// ①

        try {
            FileUtils.writeByteArrayToFile(new File("e:/upload/" + file.getOriginalFilename()),file.getBytes()); // ②
            return "ok";
        } catch (IOException e) {
            e.printStackTrace();
            return "wrong";
        }
    }
}