springMVC配置环境实现文件上传和下载

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：

如果文件不存在，报错如下：

以上就是本文的全部内容，希望对大家的学习有所帮助。