SpringMVC单/多文件上传

以你之姓@ 2022-05-20 02:00 319阅读 0赞

### 文件上传 ###

###### 文件上传是项目开发中最常见的功能。为了能上传文件，必须将表单的method设置为POST，并将enctype设置为multipart/form-data。只有在这样的情况下，浏览器才会把用户选择的文件以二进制数据发送给服务器。 ######

###### 一旦设置了enctype为multipart/form-data，浏览器即会采用二进制流的方式来处理表单数据，而对于文件上传的处理则涉及在服务器端解析原始的HTTP响应。 ######

--------------------

#### 在POM中添加文件上传的JAR包依赖 ####

<dependency>
          <groupId>org.springframework</groupId>
          <artifactId>spring-webmvc</artifactId>
          <version>3.2.8.RELEASE</version>
        </dependency>
        <dependency>
    		<groupId>commons-fileupload</groupId>
    		<artifactId>commons-fileupload</artifactId>
    		<version>1.3.1</version>
    	</dependency>
        <dependency>
          <groupId>commons-io</groupId>
          <artifactId>commons-io</artifactId>
          <version>2.5</version>
        </dependency>

#### 在spring-mvc.xml中添加代码： ####

<bean id="multipartResolver" 
            class="org.springframework.web.multipart.commons.CommonsMultipartResolver">
            <property name="defaultEncoding" value="utf-8"></property>
            <property name="maxUploadSize" value="10485760000"></property>
            <property name="maxInMemorySize" value="40960"></property>
        </bean>

#### 控制层代码: ####

FileUploadController.java

@Api(value = "文件上传操作接口", tags = {"FileUploadController"})
    @RestController
    @RequestMapping("/FileUpload")
    public class FileUploadController {
        @Resource
        private SpringUpload springUpload;
        
        
        /**
         * @params [request]
         * @creator Conn
         * @date 2018/7/6
         * @description 单个多个文件上传接口
         */
        @ApiOperation(value = "单个多个文件上传接口", httpMethod = "POST", response = ResultInfo.class)
        @PostMapping(value = "/FileUpload", produces = {"application/json"})
        public ResultInfo FileUpload(HttpServletRequest request) {
            ResultInfo success = ResultInfo.success();
            
            try {
                Map<Integer, FastDFSFile> fastDFSFileMap = springUpload.springUpload(request);
                success.build(fastDFSFileMap);
            } catch (IOException e) {
                e.printStackTrace();
                ResultInfo.failure(e.getMessage());
            }
            return success;
        }
        
        }

#### 业务层代码: ####

SpringUpload.java

@Component
    public class SpringUpload {
    
    
    
        @Resource
        private FastDFSFileMapper fastDFSFileMapper;
    
        /*文件服务器的地址*/
        @Resource
        private FastDFSValueConfig fastDFSValueConfig;
    
        /*采用spring提供的文件上传*/
        public Map<Integer, FastDFSFile> springUpload(HttpServletRequest request) throws IllegalStateException, IOException {
    
            FastDFSFile fastDFSFile = null;
            Map<Integer, FastDFSFile> fastDFSFileMap = new HashMap<>();
    
            //将当前上下文初始化给  CommonsMutipartResolver （多部分解析器）
            CommonsMultipartResolver cmr = new CommonsMultipartResolver(request.getSession().getServletContext());
            //检查form中是否有enctype="multipart/form-data"
            if (cmr.isMultipart(request)) {
                //将request变成多部分request
                MultipartHttpServletRequest msr = (MultipartHttpServletRequest) request;
                //获取multiRequest 中所有的文件名
                Iterator iter = msr.getFileNames();
    
    
    
                while (iter.hasNext()) {
                    //一次遍历所有文件
                    List<MultipartFile> files = msr.getFiles(iter.next().toString());
                    if (files != null) {
                        try {
                            for (MultipartFile file : files) {
                                //得到文件初始的名字
                                String fileOriginalName = file.getOriginalFilename();
                                // 取文件格式后缀名
                                String extName = fileOriginalName.substring(fileOriginalName.indexOf(".") + 1);
    
                                //得到文件在服务器的路径
                                String path = FastDFSUtil.uploadFile(file.getBytes(), extName);
    
                                //上传
                                file.transferTo(new File(fileOriginalName));
    
    
                                Double size = Double.valueOf(file.getSize());
    
                                fastDFSFile = new FastDFSFile();
                                Date timeStamp = Date.from(Instant.now());
    
                                //把值放到对象里
                                fastDFSFile.setFileOriginalName(fileOriginalName);
                                fastDFSFile.setFileOriginalSize(size);
                                fastDFSFile.setFileServerPath(path);
                                fastDFSFile.setFileUploadTime(timeStamp);
    
                                //添加文件信息进fastdfs_file表
                                fastDFSFileMapper.insert(fastDFSFile);
    
                               
                               //拼接为文件在服务器真实的地址 fastDFSFile.setFileServerPath(fastDFSValueConfig.getFastdfsAddress() + path);
                                fastDFSFileMap.put(fastDFSFile.getId(), fastDFSFile);
                            }
                        } catch (Exception e) {
                            e.printStackTrace();
                        }
                    }
                }
    
            }
            return fastDFSFileMap;
        }
    
    }

#### 用来加载文件服务器的配置文件Bean ####

FastDFSValueConfig.java

@Component
    @PropertySource(value = "classpath:config/config_fastdfs.properties")
    public class FastDFSValueConfig {
    
        @Value("${fastdfs.address.}")
        private String fastdfsAddress;
    
        public String getFastdfsAddress() {
            return fastdfsAddress;
        }
    
        public void setFastdfsAddress(String fastdfsAddress) {
            this.fastdfsAddress = fastdfsAddress;
        }
    }

#### 文件服务器配置文件 ####

fastdfs-client.properties

fastdfs.tracker_servers=127.0.0.1:22122
    fastdfs.connect_timeout_in_seconds=5
    fastdfs.charset=UTF-8
    fastdfs.http_tracker_http_port=8886

#### 测试页面 ####

<%@ page language="java" contentType="text/html; charset=UTF-8"
        pageEncoding="UTF-8"%>
    <%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %>
    <!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>springmvc-文件上传</title>
    </head>
    <body>
        <h1>使用spring MVC提供的方法上传文件</h1>
        <form name="form2" action="<c:url value='/FileUpload/FileUpload/>" method="post" enctype="multipart/form-data">
            <input type="file" name="file"/>
            <input type="submit" value="fileupload"/>
        </form>
    </body>
    </html>

--------------------

> 综上 该接口博主测试成功，可以上传单/多个文件,并返回上传文件的信息。当然了,各位需要自己搭建文件服务器,如果不会的可以参考博主之前一个帖子。  
> [搭建文件服务器][Link 1]

[Link 1]: https://blog.csdn.net/tzconn/article/details/79318511