spring mvc(注解)上传文件的简单例子,这有几个需要注意的地方
1.form的enctype=”multipart/form-data” 这个是上传文件必须的
2.applicationContext.xml中 <bean id=”multipartResolver” class=”org.springframework.web.multipart.commons.CommonsMultipartResolver”/> 关于文件上传的配置不能少

大家可以看具体代码如下:

web.xml

<?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"> 
  <display-name>webtest</display-name> 
 
  <listener> 
        <listener-class>org.springframework.web.context.ContextLoaderListener</listener-class> 
    </listener> 
    <context-param> 
        <param-name>contextConfigLocation</param-name> 
        <param-value> 
            /WEB-INF/config/applicationContext.xml 
            /WEB-INF/config/codeifAction.xml 
        </param-value> 
    </context-param> 
 
    <servlet> 
        <servlet-name>dispatcherServlet</servlet-name> 
        <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class> 
        <init-param> 
            <param-name>contextConfigLocation</param-name> 
            <param-value>/WEB-INF/config/codeifAction.xml</param-value> 
        </init-param> 
        <load-on-startup>1</load-on-startup> 
    </servlet> 
    <!-- 拦截所有以do结尾的请求 --> 
    <servlet-mapping> 
        <servlet-name>dispatcherServlet</servlet-name> 
        <url-pattern>*.do</url-pattern> 
    </servlet-mapping> 
 
  <welcome-file-list> 
    <welcome-file>index.do</welcome-file> 
  </welcome-file-list> 
</web-app>

applicationContext.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" 
    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" 
    default-lazy-init="true"> 
 
    <!-- 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" lazy-init="false" /> 
 
    <!-- 另外最好还要加入DefaultAnnotationHandlerMapping，不然会被 XML或其它的映射覆盖！ --> 
    <bean class="org.springframework.web.servlet.mvc.annotation.DefaultAnnotationHandlerMapping" /> 
 
    <!-- 对模型视图名称的解析，即在模型视图名称添加前后缀 --> 
    <bean class="org.springframework.web.servlet.view.InternalResourceViewResolver" p:prefix="/WEB-INF/jsp/" p:suffix=".jsp" /> 
 
    <!-- 支持上传文件 --> 
    <bean id="multipartResolver" class="org.springframework.web.multipart.commons.CommonsMultipartResolver"/> 
 
</beans>

codeifAction.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" 
    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" 
    default-lazy-init="true"> 
 
    <bean id="uploadAction" class="com.codeif.action.UploadAction" /> 
 
</beans>

UploadAction.java

package com.codeif.action; 
 
import java.io.File; 
import java.util.Date; 
 
import javax.servlet.http.HttpServletRequest; 
 
import org.springframework.stereotype.Controller; 
import org.springframework.ui.ModelMap; 
import org.springframework.web.bind.annotation.RequestMapping; 
import org.springframework.web.bind.annotation.RequestParam; 
import org.springframework.web.multipart.MultipartFile; 
 
@Controller 
public class UploadAction { 
 
    @RequestMapping(value = "/upload.do") 
    public String upload(@RequestParam(value = "file", required = false) MultipartFile file, HttpServletRequest request, ModelMap model) { 
 
        System.out.println("开始"); 
        String path = request.getSession().getServletContext().getRealPath("upload"); 
        String fileName = file.getOriginalFilename(); 
//        String fileName = new Date().getTime()+".jpg"; 
        System.out.println(path); 
        File targetFile = new File(path, fileName); 
        if(!targetFile.exists()){ 
            targetFile.mkdirs(); 
        } 
 
        //保存 
        try { 
            file.transferTo(targetFile); 
        } catch (Exception e) { 
            e.printStackTrace(); 
        } 
        model.addAttribute("fileUrl", request.getContextPath()+"/upload/"+fileName); 
 
        return "result"; 
    } 
 
}

index.jsp

<%@ page pageEncoding="utf-8"%> 
<!DOCTYPE html> 
<html> 
<head> 
<meta charset="utf-8"> 
<title>上传图片</title> 
</head> 
<body> 
<form action="upload.do" method="post" enctype="multipart/form-data"> 
<input type="file" name="file" /> <input type="submit" value="Submit" /></form> 
</body> 
</html>

WEB-INF/jsp/下的result.jsp

<%@ page pageEncoding="utf-8"%> 
<!DOCTYPE html> 
<html> 
<head> 
<meta charset="utf-8"> 
<title>上传结果</title> 
</head> 
<body> 
<img alt="" src="${fileUrl }" /> 
</body> 
</html>