使用springMVC实现文件上传和下载之环境配置与上传

最近的项目中用到了文件的上传和下载功能，任务分配给了其他的同时完成。如今项目结束告一段落，我觉着这个功能比较重要，因此特意把它提取出来自己进行了尝试。

一、 基础配置：

maven导包及配置pom.xml，导包时除开springmvc的基础依赖外，需要导入文件上传下载时用到的commons-io.jsr和commons-fileupload.jar：

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1. <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
2. xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/maven-v4_0_0.xsd">
3. <modelVersion>4.0.0</modelVersion>
4. <groupId>filLoadTest</groupId>
5. <artifactId>filLoadTest</artifactId>
6. <packaging>war</packaging>
7. <version>0.0.1-SNAPSHOT</version>
8. <name>filLoadTest Maven Webapp</name>
9. <url>http://maven.apache.org</url>
10. <build>
11. <finalName>filLoadTest</finalName>
12. <plugins>
13. <!-- 以下配置可以保证每次强制更新时jre版本不会变化，那我的eclipse4.4.1，maven3.2.5为例，如果不设置这个，每次强制更新时jre就会变回1.5 -->
14. <plugin>
15. <artifactId>maven-compiler-plugin</artifactId>
16. <version>2.3.2</version>
17. <configuration>
18. <source>1.7</source>
19. <target>1.7</target>
20. <encoding>UTF-8</encoding>
21. <compilerArguments>
22. <verbose />
23. <bootclasspath>${java.home}\lib\rt.jar</bootclasspath>
24. </compilerArguments>
25. </configuration>
26. </plugin>
27. </plugins>
28. </build>
29. <dependencies>
30. <dependency>
31. <groupId>junit</groupId>
32. <artifactId>junit</artifactId>
33. <version>3.8.1</version>
34. <scope>test</scope>
35. </dependency>
36. <dependency>
37. <groupId>org.springframework</groupId>
38. <artifactId>spring-webmvc</artifactId>
39. <version>4.0.6.RELEASE</version>
40. </dependency>
41. <dependency>
42. <groupId>com.fasterxml.jackson.core</groupId>
43. <artifactId>jackson-annotations</artifactId>
44. <version>2.2.3</version>
45. </dependency>
46. <dependency>
47. <groupId>com.fasterxml.jackson.core</groupId>
48. <artifactId>jackson-core</artifactId>
49. <version>2.2.3</version>
50. </dependency>
51. <dependency>
52. <groupId>com.fasterxml.jackson.core</groupId>
53. <artifactId>jackson-databind</artifactId>
54. <version>2.2.3</version>
55. </dependency>
56. <dependency>
57. <groupId>commons-fileupload</groupId>
58. <artifactId>commons-fileupload</artifactId>
59. <version>1.3.1</version>
60. </dependency>
61. <dependency>
62. <groupId>commons-io</groupId>
63. <artifactId>commons-io</artifactId>
64. <version>2.4</version>
65. </dependency>
66. </dependencies>
67. </project>

web.xml基础配置：

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1. <?xml version="1.0" encoding="UTF-8"?>
2. <web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
3. xmlns="http://java.sun.com/xml/ns/javaee" xmlns:web="http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd"
4. xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd"
5. id="WebApp_ID" version="2.5">
6. <filter>
7. <description>字符集过滤器</description>
8. <filter-name>encodingFilter</filter-name>
9. <filter-class>org.springframework.web.filter.CharacterEncodingFilter</filter-class>
10. <init-param>
11. <description>字符集编码</description>
12. <param-name>encoding</param-name>
13. <param-value>UTF-8</param-value>
14. </init-param>
15. </filter>
16. <filter-mapping>
17. <filter-name>encodingFilter</filter-name>
18. <url-pattern>/*</url-pattern>
19. </filter-mapping>
20. <servlet>
21. <servlet-name>springMVC</servlet-name>
22. <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
23. <init-param>
24. <param-name>contextConfigLocation</param-name>
25. <param-value>classpath:spring.xml</param-value>
26. </init-param>
27. </servlet>
28. <servlet-mapping>
29. <servlet-name>springMVC</servlet-name>
30. <url-pattern>*.do</url-pattern>
31. </servlet-mapping>
32. <welcome-file-list>
33. <welcome-file>index.html</welcome-file>
34. <welcome-file>index.htm</welcome-file>
35. <welcome-file>index.jsp</welcome-file>
36. <welcome-file>default.html</welcome-file>
37. <welcome-file>default.htm</welcome-file>
38. <welcome-file>default.jsp</welcome-file>
39. </welcome-file-list>
40. </web-app>

spring基础配置spring.xml:

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1. <?xml version="1.0" encoding="UTF-8"?>
2. <beans xmlns="http://www.springframework.org/schema/beans"
3. xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:p="http://www.springframework.org/schema/p"
4. xmlns:context="http://www.springframework.org/schema/context"
5. xmlns:mvc="http://www.springframework.org/schema/mvc"
6. xsi:schemaLocation="
7. http://www.springframework.org/schema/beans
8. http://www.springframework.org/schema/beans/spring-beans-3.0.xsd
9. http://www.springframework.org/schema/context
10. http://www.springframework.org/schema/context/spring-context-3.0.xsd
11. http://www.springframework.org/schema/mvc
12. http://www.springframework.org/schema/mvc/spring-mvc.xsd">
13. <context:annotation-config />
14. <mvc:annotation-driven />
15. <context:component-scan base-package="controllers" />
16. <!-- 避免IE执行AJAX时,返回JSON出现下载文件 -->
17. <bean id="mappingJacksonHttpMessageConverter"
18. class="org.springframework.http.converter.json.MappingJackson2HttpMessageConverter">
19. <property name="supportedMediaTypes">
20. <list>
21. <value>text/html;charset=utf-8</value>
22. </list>
23. </property>
24. </bean>
25. <!-- 启动Spring MVC的注解功能，完成请求和注解POJO的映射 -->
26. <bean
27. class="org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter">
28. <property name="messageConverters">
29. <list>
30. <ref bean="mappingJacksonHttpMessageConverter" /><!-- json转换器 -->
31. </list>
32. </property>
33. </bean>
34. <!-- 支持上传文件 -->
35. <bean id="multipartResolver"
36. class="org.springframework.web.multipart.commons.CommonsMultipartResolver" >
37. <!-- 100M -->
38. <property name="maxUploadSize" value="104857600"></property>
39. <property name="defaultEncoding" value="utf-8"></property>
40. </bean>
41. </beans>

二、文件上传的代码

上传的简单页面index.html,要注意form表单提交时的entype的设置：

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1. <!DOCTYPE html>
2. <html>
3. <head>
4. <meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
5. </head>
6. <body>
7. <form action="./upLoadFile.do" method="post" enctype="multipart/form-data">
8. 选择文件：<input type="file" name="file"/>
9. <input type="submit" value="提交"/>
10. </form>
11. </body>
12. </html>

上传对应的后台java代码，具体问题见注释：

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1. package controllers;
2. import java.io.File;
3. import java.io.IOException;
4. import java.util.Iterator;
5. import javax.servlet.http.HttpServletRequest;
6. import org.apache.commons.io.FileUtils;
7. import org.springframework.http.HttpHeaders;
8. import org.springframework.http.HttpStatus;
9. import org.springframework.http.MediaType;
10. import org.springframework.http.ResponseEntity;
11. import org.springframework.stereotype.Controller;
12. import org.springframework.web.bind.annotation.RequestMapping;
13. import org.springframework.web.bind.annotation.RequestMethod;
14. import org.springframework.web.bind.annotation.RequestParam;
15. import org.springframework.web.multipart.MultipartFile;
16. import org.springframework.web.multipart.MultipartHttpServletRequest;
17. import org.springframework.web.multipart.commons.CommonsMultipartResolver;
18. @Controller
19. public class fileController {
20. /**
21. * 文件上传
22. *
23. * @author：tuzongxun
24. * @Title: upLoadFile
25. * @param @param file
26. * @param @param request
27. * @param @throws IllegalStateException
28. * @param @throws IOException
29. * @return void
30. * @date Apr 28, 2016 1:22:00 PM
31. * @throws
32. */
33. @RequestMapping(value = "/upLoadFile.do", method = RequestMethod.POST)
34. public void upLoadFile(HttpServletRequest request)
35. throws IllegalStateException, IOException {
36. // @RequestParam("file") MultipartFile file,
37. CommonsMultipartResolver multipartResolver = new CommonsMultipartResolver(
38. request.getSession().getServletContext());
39. // 判断 request 是否有文件上传,即多部分请求
40. if (multipartResolver.isMultipart(request)) {
41. // 转换成多部分request
42. MultipartHttpServletRequest multiRequest = (MultipartHttpServletRequest) request;
43. // 取得request中的所有文件名
44. Iterator<String> iter = multiRequest.getFileNames();
45. while (iter.hasNext()) {
46. // 取得上传文件
47. MultipartFile f = multiRequest.getFile(iter.next());
48. if (f != null) {
49. // 取得当前上传文件的文件名称
50. String myFileName = f.getOriginalFilename();
51. // 如果名称不为“”,说明该文件存在，否则说明该文件不存在
52. if (myFileName.trim() != "") {
53. // 定义上传路径
54. String path = "C:\\Users\\tuzongxun123\\Desktop\\"
55. + myFileName;
56. File localFile = new File(path);
57. f.transferTo(localFile);
58. }
59. }
60. }
61. }
62. }
63. }

页面效果图如下，当选择文件提交后，便会看到选中的文件被传到了代码中指定的位置，这里是我的桌面上。