springMVC配置环境实现文件上传和下载

2019-11-26 14:18:48

字体：大中小

来源：转载

供稿：网友

最近的项目中用到了文件的上传和下载功能，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。

下面就是springMVC配置环境实现文件上传和下载的具体步骤，供大家参考，具体内容如下

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：

<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"  xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/maven-v4_0_0.xsd">  <modelVersion>4.0.0</modelVersion>  <groupId>filLoadTest</groupId>  <artifactId>filLoadTest</artifactId>  <packaging>war</packaging>  <version>0.0.1-SNAPSHOT</version>  <name>filLoadTest Maven Webapp</name>  <url>http://maven.apache.org</url>  <build>  <finalName>filLoadTest</finalName>  <plugins>   <!-- 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 -->   <plugin>   <artifactId>maven-compiler-plugin</artifactId>   <version>2.3.2</version>   <configuration>    <source>1.7</source>    <target>1.7</target>    <encoding>UTF-8</encoding>    <compilerArguments>    <verbose />    <bootclasspath>${java.home}/lib/rt.jar</bootclasspath>    </compilerArguments>   </configuration>   </plugin>  </plugins>  </build>  <dependencies>  <dependency>  <groupId>junit</groupId>  <artifactId>junit</artifactId>  <version>3.8.1</version>  <scope>test</scope>  </dependency>  <dependency>  <groupId>org.springframework</groupId>  <artifactId>spring-webmvc</artifactId>  <version>4.0.6.RELEASE</version>  </dependency>  <dependency>  <groupId>com.fasterxml.jackson.core</groupId>  <artifactId>jackson-annotations</artifactId>  <version>2.2.3</version>  </dependency>  <dependency>  <groupId>com.fasterxml.jackson.core</groupId>  <artifactId>jackson-core</artifactId>  <version>2.2.3</version>  </dependency>  <dependency>  <groupId>com.fasterxml.jackson.core</groupId>  <artifactId>jackson-databind</artifactId>  <version>2.2.3</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>2.4</version>  </dependency>  </dependencies> </project>

web.xml基础配置：

<?xml version="1.0" encoding="UTF-8"?> <web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"  xmlns="http://java.sun.com/xml/ns/javaee" xmlns:web="http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd"  xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd"  id="WebApp_ID" version="2.5">  <filter>  <description>字符集过滤器</description>  <filter-name>encodingFilter</filter-name>  <filter-class>org.springframework.web.filter.CharacterEncodingFilter</filter-class>  <init-param>   <description>字符集编码</description>   <param-name>encoding</param-name>   <param-value>UTF-8</param-value>  </init-param>  </filter>  <filter-mapping>  <filter-name>encodingFilter</filter-name>  <url-pattern>/*</url-pattern>  </filter-mapping>  <servlet>  <servlet-name>springMVC</servlet-name>  <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>  <init-param>   <param-name>contextConfigLocation</param-name>   <param-value>classpath:spring.xml</param-value>  </init-param>  </servlet>  <servlet-mapping>  <servlet-name>springMVC</servlet-name>  <url-pattern>*.do</url-pattern>  </servlet-mapping>  <welcome-file-list>  <welcome-file>index.html</welcome-file>  <welcome-file>index.htm</welcome-file>  <welcome-file>index.jsp</welcome-file>  <welcome-file>default.html</welcome-file>  <welcome-file>default.htm</welcome-file>  <welcome-file>default.jsp</welcome-file>  </welcome-file-list> </web-app>

spring基础配置spring.xml:

<?xml version="1.0" encoding="UTF-8"?> <beans xmlns="http://www.springframework.org/schema/beans"  xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:p="http://www.springframework.org/schema/p"  xmlns:context="http://www.springframework.org/schema/context"  xmlns:mvc="http://www.springframework.org/schema/mvc"  xsi:schemaLocation="  http://www.springframework.org/schema/beans  http://www.springframework.org/schema/beans/spring-beans-3.0.xsd  http://www.springframework.org/schema/context  http://www.springframework.org/schema/context/spring-context-3.0.xsd  http://www.springframework.org/schema/mvc  http://www.springframework.org/schema/mvc/spring-mvc.xsd">    <context:annotation-config />  <mvc:annotation-driven />  <context:component-scan base-package="controllers" />   <!-- 避免IE执行AJAX时,返回JSON出现下载文件 -->  <bean id="mappingJacksonHttpMessageConverter"  class="org.springframework.http.converter.json.MappingJackson2HttpMessageConverter">  <property name="supportedMediaTypes">   <list>   <value>text/html;charset=utf-8</value>   </list>  </property>  </bean>    <!-- 启动Spring MVC的注解功能，完成请求和注解POJO的映射 -->  <bean  class="org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter">  <property name="messageConverters">   <list>   <ref bean="mappingJacksonHttpMessageConverter" /><!-- json转换器 -->   </list>  </property>  </bean>   <!-- 支持上传文件 -->  <bean id="multipartResolver"  class="org.springframework.web.multipart.commons.CommonsMultipartResolver" >  <!-- 100M -->  <property name="maxUploadSize" value="104857600"></property>  <property name="defaultEncoding" value="utf-8"></property>  </bean> </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：

<!DOCTYPE html> <html> <head>  <meta http-equiv="Content-Type" content="text/html; charset=utf-8" /> </head> <body>  <form action="./upLoadFile.do" method="post" enctype="multipart/form-data">    选择文件：<input type="file" name="file"/>    <input type="submit" value="提交"/>  </form> </body> </html>

上传对应的后台java代码，具体问题见注释：

package controllers;   import java.io.File; import java.io.IOException; import java.util.Iterator; import javax.servlet.http.HttpServletRequest; import org.apache.commons.io.FileUtils; import org.springframework.http.HttpHeaders; import org.springframework.http.HttpStatus; import org.springframework.http.MediaType; import org.springframework.http.ResponseEntity; 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.RequestParam; import org.springframework.web.multipart.MultipartFile; import org.springframework.web.multipart.MultipartHttpServletRequest; import org.springframework.web.multipart.commons.CommonsMultipartResolver;   @Controller public class fileController {    /**  * 文件上传  *  * @author：tuzongxun  * @Title: upLoadFile  * @param @param file  * @param @param request  * @param @throws IllegalStateException  * @param @throws IOException  * @return void  * @date Apr 28, 2016 1:22:00 PM  * @throws  */  @RequestMapping(value = "/upLoadFile.do", method = RequestMethod.POST)  public void upLoadFile(HttpServletRequest request)   throws IllegalStateException, IOException {  // @RequestParam("file") MultipartFile file,  CommonsMultipartResolver multipartResolver = new CommonsMultipartResolver(   request.getSession().getServletContext());  // 判断 request 是否有文件上传,即多部分请求  if (multipartResolver.isMultipart(request)) {   // 转换成多部分request   MultipartHttpServletRequest multiRequest = (MultipartHttpServletRequest) request;   // 取得request中的所有文件名   Iterator<String> iter = multiRequest.getFileNames();   while (iter.hasNext()) {   // 取得上传文件   MultipartFile f = multiRequest.getFile(iter.next());   if (f != null) {    // 取得当前上传文件的文件名称    String myFileName = f.getOriginalFilename();    // 如果名称不为“”,说明该文件存在，否则说明该文件不存在    if (myFileName.trim() != "") {    // 定义上传路径    String path = "C://Users//tuzongxun123//Desktop//"     + myFileName;    File localFile = new File(path);    f.transferTo(localFile);    }   }   }  }  } }

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，页面效果图如下

三、文件下载

文件下载需要获取下载文件的存储路径，这里只是手动填入，如果是在具体项目中，可以把文件名和上传后的存储路径保存在数据库中。然后增加一个文件列表的页面展示文件名和文件路径，然后点击下载的时候把相应的文件名和路径传到后台操作。

/**   * 文件下载，需要文件名和文件地址   *   * @author：tuzongxun   * @Title: download   * @param@param name   * @param@param path   * @param@return   * @param@throws IOException   * @returnResponseEntity<byte[]>   * @date Apr 28,2016 1:21:32 PM   * @throws   */  @RequestMapping(value = "/downLoadFile.do")  public ResponseEntity<byte[]> download(@RequestParam("name") String name,    @RequestParam("filePath") String path) throws IOException {   File file = new File(path);   HttpHeaders headers = new HttpHeaders();   String fileName = new String(name.getBytes("UTF-8"), "iso-8859-1");// 为了解决中文名称乱码问题   headers.setContentDispositionFormData("attachment", fileName);   headers.setContentType(MediaType.APPLICATION_OCTET_STREAM);   return new ResponseEntity<byte[]>(FileUtils.readFileToByteArray(file),     headers, HttpStatus.CREATED);  }

Html页面，这里只是简单的填写文件名和文件路径，用form表单提交到后台，然后后台会控制response在页面弹出保存文件路径的选择框，当然了，这里的后台我没有做什么处理，如果文件不存在是会报错的，可以进行相应的处理：
文件下载：

 </br> </br>  <form action="./downLoadFile.do"style="border:1px solid grey;width:auto;" method="post">    文件名：<input type="text" name="name"/></br></br>    文件路径：<input type="text" name="filePath"/></br></br>    <input type="submit" value="确认下载"/>  </form>

页面视图如下：