java后台开发SpringMVC例子--图片上传下载

java后台开发SpringMVC例子–图片上传下载

环境：

win7；jdk1.8_121；tomact8.0；Mysql；spring-4.3.0。需要安装及配置好jdk，mysql。

完整代码下载（需要的jar包已放在lib下）
：http://download.csdn.net/download/yhhyhhyhhyhh/9913431

1.配置

连接数据库需要：mysql-connector-java-5.0.8-bin.jar

服务器上运行servlet需要：servlet-api.jar

文件上传需要：

com.springsource.org.apache.commons.fileupload-1.2.0.jar

com.springsource.org.apache.commons.io-1.4.0.jar

web.xml配置：

<?xml version="1.0" encoding="UTF-8"?><web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://xmlns.jcp.org/xml/ns/javaee" xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee http://xmlns.jcp.org/xml/ns/javaee/web-app_3_1.xsd" id="WebApp_ID" version="3.1">  <display-name>TestOA</display-name>  <welcome-file-list>    <welcome-file>/WEB-INF/views/index.jsp</welcome-file>  </welcome-file-list>  <servlet>          <servlet-name>oa</servlet-name>          <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>          <!-- load-on-startup：表示启动容器时初始化该Servlet； -->          <load-on-startup>1</load-on-startup>      </servlet>      <servlet-mapping>          <servlet-name>oa</servlet-name>          <!-- url-pattern：表示哪些请求交给Spring Web MVC处理， “/” 是用来定义默认servlet映射的。 -->          <!-- 也可以如“*.html”表示拦截所有以html为扩展名的请求。 -->          <url-pattern>/</url-pattern>       </servlet-mapping>      <!-- 编码过滤器 -->     <filter>        <filter-name>encodingFilter</filter-name>        <filter-class>org.springframework.web.filter.CharacterEncodingFilter </filter-class>        <init-param>            <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></web-app>

servlet配置（这里为：oa-servlet.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:context="http://www.springframework.org/schema/context"  xmlns:p="http://www.springframework.org/schema/p"  xmlns:mvc="http://www.springframework.org/schema/mvc"  xsi:schemaLocation="http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc-4.0.xsd      http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd      http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-4.0.xsd">  <!-- spring扫描注解的包 -->  <context:component-scan base-package="com.springmvc.test" />  <!-- 在Spring配置文件中配置ViewResolver -->  <!-- InternalResourceViewResolver：用于支持Servlet、JSP视图解析；         prefix和suffix：查找视图页面的前缀和后缀（前缀[逻辑视图名]后缀），       比如传进来的逻辑视图名为hello，则该该jsp视图页面应该存放在“WEB-INF/views/hello.jsp”；    -->      <bean class="org.springframework.web.servlet.view.InternalResourceViewResolver">          <property name="prefix" value="/WEB-INF/views/" />          <property name="suffix" value=".jsp" />      </bean>       <!--文件上传解析器配置 -->    <bean id="multipartResolver"    class="org.springframework.web.multipart.commons.CommonsMultipartResolver">    <!-- 上传文件的总大小和单个文件的大小 -->    <property name="maxUploadSize" value="12345678900"/>        <property name="maxInMemorySize" value="10240100"/>        <property name="defaultEncoding" value="UTF-8"/></bean></beans>

数据库信息：

核心代码部分。

package com.springmvc.test;import java.io.File;import java.io.IOException;import java.text.SimpleDateFormat;import java.util.Date;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.ui.Model;import org.springframework.web.bind.annotation.RequestMapping;import org.springframework.web.bind.annotation.RequestParam;import org.springframework.web.multipart.commons.CommonsMultipartFile;/* * @Controller表示类注解 * @RequestMapping表示controller指定的URL * @RequestParam：根据参数名从URL中取得参数值 */@Controllerpublic class UpDownLoad {    @RequestMapping("/login")       public String login(@RequestParam("username") String name, @RequestParam("password") String pass,                Model model) {           LoginModel newModel=new LoginModel();        newModel.setName(name);        newModel.setPas(pass);        if(newModel.login())        {            model.addAttribute("username", name);//传递参数            return "menu";        }        else        {   model.addAttribute("username", name);            return "index";        }      }         @RequestMapping("/fileupload")         public String upload(@RequestParam("image") CommonsMultipartFile image ,                 HttpServletRequest request) throws IllegalStateException, IOException  {             //解析路径             String imgFolder =request.getSession().getServletContext().getRealPath("/fileupload");             //解析文件名             String imgUrl = new SimpleDateFormat("yyyyMMddHHmmss").format(new Date())+image.getOriginalFilename();             //新建file对象             File targetImg = new File(imgFolder ,imgUrl);                 String type=null;// 文件类型                 type=imgUrl.indexOf(".")!=-1?imgUrl.substring(imgUrl.lastIndexOf(".")+1, imgUrl.length()):null;                 if (type!=null)                  {// 判断文件类型是否为空                 if ("GIF".equals(type.toUpperCase())||"PNG".equals(type.toUpperCase())||"JPG".equals(type.toUpperCase()))                  {                     //判断文件是否存在                     if (!targetImg.exists()){                         targetImg.mkdirs();//不存在新建                     }                    image.transferTo(targetImg);                     return "upsuccess";                 }                 }                 return "upfail";         }         @RequestMapping("/filedownload")         public ResponseEntity<byte[]> download() throws IOException {                  HttpHeaders headers = new HttpHeaders();                 // String fileUrl="D:\\test.txt";               String fileUrl="D:\\test.jpg";                File file= new File(fileUrl);                headers.setContentType(MediaType.APPLICATION_OCTET_STREAM);                  String charset=new String(fileUrl.getBytes("utf-8"),"iso-8859-1");                headers.setContentDispositionFormData("file", charset);                  return new ResponseEntity<byte[]>(FileUtils.readFileToByteArray(file),                                                    headers, HttpStatus.CREATED);         } }

2.测试

​ 图片上传:

​

图片下载：

文件下载：