springMVC配置环境实现文件上传和下载
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2024-03-12 10:22:20
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...
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。