（转）SpringBoot实现MultipartFile文件上传
作者：互联网
转：SpringBoot实现MultipartFile文件上传 - 云+社区 - 腾讯云 (tencent.com)
1、SpringBoot采用FileUpload组件实现上传处理，在控制器中可以使用MultipartFile类进行接收。
1 <?xml version="1.0" encoding="UTF-8"?> 2 <project xmlns="http://maven.apache.org/POM/4.0.0" 3 xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" 4 xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 5 https://maven.apache.org/xsd/maven-4.0.0.xsd"> 6 <modelVersion>4.0.0</modelVersion> 7 <parent> 8 <groupId>org.springframework.boot</groupId> 9 <artifactId>spring-boot-starter-parent</artifactId> 10 <version>2.3.5.RELEASE</version> 11 <relativePath /> <!-- lookup parent from repository --> 12 </parent> 13 <groupId>com.example</groupId> 14 <artifactId>demo</artifactId> 15 <version>0.0.1-SNAPSHOT</version> 16 <name>demo</name> 17 <description>Demo project for Spring Boot</description> 18 19 <properties> 20 <java.version>1.8</java.version> 21 <maven-jar-plugin.version>3.1.1</maven-jar-plugin.version> 22 </properties> 23 24 <dependencies> 25 <dependency> 26 <groupId>org.springframework.boot</groupId> 27 <artifactId>spring-boot-starter-web</artifactId> 28 </dependency> 29 30 <dependency> 31 <groupId>org.springframework.boot</groupId> 32 <artifactId>spring-boot-starter-test</artifactId> 33 <scope>test</scope> 34 <exclusions> 35 <exclusion> 36 <groupId>org.junit.vintage</groupId> 37 <artifactId>junit-vintage-engine</artifactId> 38 </exclusion> 39 </exclusions> 40 </dependency> 41 <!-- https://mvnrepository.com/artifact/org.hibernate/hibernate-validator --> 42 <dependency> 43 <groupId>org.hibernate</groupId> 44 <artifactId>hibernate-validator</artifactId> 45 <version>6.1.0.Final</version> 46 </dependency> 47 <dependency> 48 <groupId>org.springframework.boot</groupId> 49 <artifactId>spring-boot-starter-thymeleaf</artifactId> 50 </dependency> 51 </dependencies> 52 53 <build> 54 <plugins> 55 <plugin> 56 <groupId>org.springframework.boot</groupId> 57 <artifactId>spring-boot-maven-plugin</artifactId> 58 </plugin> 59 </plugins> 60 <resources> 61 <resource> 62 <directory>src/main/resources</directory> 63 <includes> 64 <include>**/*.properties</include> 65 <include>**/*.yml</include> 66 <include>**/*.xml</include> 67 <include>**/*.p12</include> 68 <include>**/*.html</include> 69 <include>**/*.jpg</include> 70 <include>**/*.png</include> 71 </includes> 72 </resource> 73 </resources> 74 </build> 75 76 </project>
创建控制器类UploadController，利用MultipartFile将上传文件保存在本地磁盘。
1 package com.demo.controller;
2
3 import java.io.File;
4 import java.io.IOException;
5 import java.util.HashMap;
6 import java.util.Map;
7 import java.util.UUID;
8
9 import org.springframework.stereotype.Controller;
10 import org.springframework.web.bind.annotation.RequestMapping;
11 import org.springframework.web.bind.annotation.RequestMethod;
12 import org.springframework.web.bind.annotation.RequestParam;
13 import org.springframework.web.bind.annotation.ResponseBody;
14 import org.springframework.web.context.request.RequestAttributes;
15 import org.springframework.web.context.request.RequestContextHolder;
16 import org.springframework.web.context.request.ServletRequestAttributes;
17 import org.springframework.web.multipart.MultipartFile;
18
19 /**
20 *
21 * @author
22 *
23 */
24 @Controller
25 public class UploadController {
26
27 /**
28 * 首先根据此方法跳转到upload.html界面
29 *
30 * @return
31 */
32 @RequestMapping(value = "/upload_pre", method = RequestMethod.GET)
33 public String uploadPre() {
34 return "upload";
35 }
36
37 /**
38 * 文件上传
39 *
40 * @param name
41 * @param multipartFile
42 * @return
43 * @throws IllegalStateException
44 * @throws IOException
45 */
46 @RequestMapping(value = "/upload", method = RequestMethod.POST)
47 @ResponseBody
48 public Object upload(String name, @RequestParam(value = "multipartFile") MultipartFile multipartFile)
49 throws IllegalStateException, IOException {
50 Map<String, Object> map = new HashMap<String, Object>();
51 if (multipartFile != null) {
52 // 设置文件名称
53 map.put("nameParam", name);
54 // 设置文件名称
55 map.put("fileame", multipartFile.getName());
56 // 设置文件类型
57 map.put("contentType", multipartFile.getContentType());
58 // 设置文件大小
59 map.put("fileSize", multipartFile.getSize());
60 // 创建文件名称
61 String fileName = UUID.randomUUID() + "."
62 + multipartFile.getContentType().substring(multipartFile.getContentType().lastIndexOf("/") + 1);
63 // 获取到文件的路径信息
64 RequestAttributes requestAttributes = RequestContextHolder.getRequestAttributes();
65 ServletRequestAttributes servletRequestAttributes = (ServletRequestAttributes) requestAttributes;
66 String filePath = servletRequestAttributes.getRequest().getServletContext().getRealPath("/") + fileName;
67 // 打印保存路径
68 System.out.println(filePath);
69 // 保存文件的路径信息
70 map.put("filePath", filePath);
71 // 创建文件
72 File saveFile = new File(filePath);
73 // 文件保存
74 multipartFile.transferTo(saveFile);
75 // 返回信息
76 return map;
77 } else {
78 return "no file ";
79 }
80 }
81
82 }
在src/main/resources/templates下面创建upload.html文件。
1 <!DOCTYPE html>
2 <html xmlns="http://www.thymeleaf.org"></html>
3 <head>
4 <meta charset="UTF-8">
5 <title>搞事情啊！！！</title>
6 </head>
7 <body>
8 <h1>搞事情啊！！！</h1>
9
10 <form th:action="@{/upload}" method="post" enctype="multipart/form-data">
11 姓名：<input type="text" name="name"/><br/>
12 <!-- 切记，这里的name="multipartFile"必须和控制层的参数一致性MultipartFile multipartFile -->
13 照片：<input type="file" name="multipartFile"/><br/>
14 <input type="submit" value="上传"/><br/>
15 </form>
16
17 </body>
18 </html>
控制层类UploadController接收到此请求信息后，如果有上传文件存在，则会直接返回上传信息（开发者也可以根据情况选择将文件保存）。
演示效果，如下所示：
2、Springboot上传文件限制，在实际项目开发中，需要对用户上传文件的大小进行限制，这样才可以保证服务器的资源不被浪费。修改application.properties配置文件，如下所示：
1 # 启用http上传 2 spring.servlet.multipart.enabled=true 3 # 设置支持的单个上传文件的大小限制 4 spring.servlet.multipart.max-file-size=10MB 5 # 设置最大的请求文件大小，设置总体大小请求 6 spring.servlet.multipart.max-request-size=20MB 7 # 当上传文件达到指定配置量的时候，将文件内容写入磁盘 8 spring.servlet.multipart.file-size-threshold=512KB 9 # 设置上传的临时目录 10 spring.servlet.multipart.location=/
对于Springboot上传文件的上传限制，也可以利用Bean实现同样的效果，实现代码，如下所示：
1 package com.demo.config;
2
3 import javax.servlet.MultipartConfigElement;
4
5 import org.springframework.boot.web.servlet.MultipartConfigFactory;
6 import org.springframework.context.annotation.Bean;
7 import org.springframework.context.annotation.Configuration;
8 import org.springframework.util.unit.DataSize;
9
10 @Configuration
11 public class UploadConfig {
12
13 @Bean
14 public MultipartConfigElement getMultipartConfig() {
15 MultipartConfigFactory config = new MultipartConfigFactory();
16 // 设置上传文件的单个大小限制
17 config.setMaxRequestSize(DataSize.parse("10MB"));
18 // 设置总的上传的大小限制
19 config.setMaxRequestSize(DataSize.parse("100MB"));
20 // 设置临时保存目录
21 config.setLocation("/");
22 // 创建一个上传配置并返回
23 return config.createMultipartConfig();
24 }
25
26 }
3、Springboot上传多个文件如果要进行多个文件的上传，需要通过MultipartHttpServletRequest进行文件接收。首先修改upload.html页面，定义多个文件上传控件。
1 <!DOCTYPE html>
2 <html xmlns="http://www.thymeleaf.org"></html>
3 <head>
4 <meta charset="UTF-8">
5 <title>搞事情啊！！！</title>
6 </head>
7 <body>
8 <h1>搞事情啊！！！</h1>
9
10 <form th:action="@{/upload}" method="post" enctype="multipart/form-data">
11 姓名：<input type="text" name="name"/><br/>
12 <!-- 切记，这里的name="multipartFile"必须和控制层的参数一致性MultipartFile multipartFile -->
13 文件一：<input type="file" name="multipartFile"/><br/>
14 文件二：<input type="file" name="multipartFile"/><br/>
15 文件三：<input type="file" name="multipartFile"/><br/>
16 <input type="submit" value="上传"/><br/>
17 </form>
18
19 </body>
20 </html>
修改UploadController.java控制器，实现多个文件上传，此时可以根据接受参数的不同，方法可以有不同的实现 ，如果接受参数是这样的，@RequestParam(value = "multipartFile") MultipartFile[] multipartFile，实现代码，如下所示：
1 package com.demo.controller;
2
3 import java.io.File;
4 import java.io.IOException;
5 import java.util.HashMap;
6 import java.util.Map;
7 import java.util.UUID;
8
9 import org.springframework.stereotype.Controller;
10 import org.springframework.web.bind.annotation.RequestMapping;
11 import org.springframework.web.bind.annotation.RequestMethod;
12 import org.springframework.web.bind.annotation.RequestParam;
13 import org.springframework.web.bind.annotation.ResponseBody;
14 import org.springframework.web.context.request.RequestAttributes;
15 import org.springframework.web.context.request.RequestContextHolder;
16 import org.springframework.web.context.request.ServletRequestAttributes;
17 import org.springframework.web.multipart.MultipartFile;
18
19 /**
20 *
21 * @author
22 *
23 */
24 @Controller
25 public class UploadController {
26
27 /**
28 * 首先根据此方法跳转到upload.html界面
29 *
30 * @return
31 */
32 @RequestMapping(value = "/upload_pre", method = RequestMethod.GET)
33 public String uploadPre() {
34 return "upload";
35 }
36
37 /**
38 * 文件上传
39 *
40 * @param name
41 * @param multipartFile
42 * @return
43 * @throws IllegalStateException
44 * @throws IOException
45 */
46 @RequestMapping(value = "/upload", method = RequestMethod.POST)
47 @ResponseBody
48 public Object upload(String name, @RequestParam(value = "multipartFile") MultipartFile[] multipartFile)
49 throws IllegalStateException, IOException {
50 Map<String, Object> map = new HashMap<String, Object>();
51 if (multipartFile != null && multipartFile.length > 0) {
52 for (int i = 0; i < multipartFile.length; i++) {
53 // 设置文件名称
54 map.put("nameParam", name);
55 // 设置文件名称
56 map.put("fileame", multipartFile[i].getName());
57 // 设置文件类型
58 map.put("contentType", multipartFile[i].getContentType());
59 // 设置文件大小
60 map.put("fileSize", multipartFile[i].getSize());
61 // 创建文件名称
62 String fileName = UUID.randomUUID() + "." + multipartFile[i].getContentType()
63 .substring(multipartFile[i].getContentType().lastIndexOf("/") + 1);
64 // 获取到文件的路径信息
65 RequestAttributes requestAttributes = RequestContextHolder.getRequestAttributes();
66 ServletRequestAttributes servletRequestAttributes = (ServletRequestAttributes) requestAttributes;
67 String filePath = servletRequestAttributes.getRequest().getServletContext().getRealPath("/") + fileName;
68 // 打印保存路径
69 System.out.println(filePath);
70 // 保存文件的路径信息
71 map.put("filePath", filePath);
72 // 创建文件
73 File saveFile = new File(filePath);
74 // 文件保存
75 multipartFile[i].transferTo(saveFile);
76 // 返回信息
77 }
78 return map;
79 } else {
80 return "no file ";
81 }
82 }
83
84 }
如果接受参数是HttpServletRequest request，代码是这样的，明显没有第一种方便，如下所示：
1 package com.demo.controller;
2
3 import java.io.File;
4 import java.io.IOException;
5 import java.util.ArrayList;
6 import java.util.HashMap;
7 import java.util.Iterator;
8 import java.util.List;
9 import java.util.Map;
10 import java.util.UUID;
11
12 import javax.servlet.http.HttpServletRequest;
13
14 import org.springframework.stereotype.Controller;
15 import org.springframework.web.bind.annotation.RequestMapping;
16 import org.springframework.web.bind.annotation.RequestMethod;
17 import org.springframework.web.bind.annotation.RequestParam;
18 import org.springframework.web.bind.annotation.ResponseBody;
19 import org.springframework.web.context.request.RequestAttributes;
20 import org.springframework.web.context.request.RequestContextHolder;
21 import org.springframework.web.context.request.ServletRequestAttributes;
22 import org.springframework.web.multipart.MultipartFile;
23 import org.springframework.web.multipart.MultipartHttpServletRequest;
24
25 /**
26 *
27 * @author
28 *
29 */
30 @Controller
31 public class UploadController {
32
33 /**
34 * 首先根据此方法跳转到upload.html界面
35 *
36 * @return
37 */
38 @RequestMapping(value = "/upload_pre", method = RequestMethod.GET)
39 public String uploadPre() {
40 return "upload";
41 }
42
43 /**
44 * 文件上传
45 *
46 * @param name
47 * @param multipartFile
48 * @return
49 * @throws IllegalStateException
50 * @throws IOException
51 */
52 @RequestMapping(value = "/upload", method = RequestMethod.POST)
53 @ResponseBody
54 public Object upload2(String name, HttpServletRequest request) throws IllegalStateException, IOException {
55 List<String> result = new ArrayList<String>();
56 if (request instanceof MultipartHttpServletRequest) {
57 MultipartHttpServletRequest multipartHttpServletRequest = (MultipartHttpServletRequest) request;
58 List<MultipartFile> files = multipartHttpServletRequest.getFiles("multipartFile");
59 Iterator<MultipartFile> iterator = files.iterator();
60 while (iterator.hasNext()) {
61 // 取出每一个文件
62 MultipartFile file = iterator.next();
63 try {
64 // 保存上传信息
65 result.add(this.saveFile(file));
66 } catch (Exception e) {
67 e.printStackTrace();
68 }
69 }
70 }
71 return result;
72 }
73
74 /**
75 * 文件保存处理
76 *
77 * @param file
78 * 上传文件
79 * @return 文件保存路径
80 * @throws Exception
81 * 上传异常
82 */
83 public String saveFile(MultipartFile multipartFile) throws Exception {
84 String filePath = "no file!!!";
85 if (multipartFile != null && multipartFile.getSize() > 0) {
86 // 创建文件名称
87 String fileName = UUID.randomUUID() + "."
88 + multipartFile.getContentType().substring(multipartFile.getContentType().lastIndexOf("/") + 1);
89 // 获取到文件的路径信息
90 RequestAttributes requestAttributes = RequestContextHolder.getRequestAttributes();
91 ServletRequestAttributes servletRequestAttributes = (ServletRequestAttributes) requestAttributes;
92 filePath = servletRequestAttributes.getRequest().getServletContext().getRealPath("/") + fileName;
93 // 打印保存路径
94 System.out.println(filePath);
95 File saveFile = new File(filePath);
96 // 文件保存
97 multipartFile.transferTo(saveFile);
98 }
99 return filePath;
100 }
101
102 }
标签：web,multipartFile,SpringBoot,springframework,org,import,MultipartFile,上传 来源： https://www.cnblogs.com/wangle1001986/p/15910763.html