Spring MVC文件上传示例详解

本文概述

• Spring MVC文件上传步骤(超出MVC)
• Spring MVC文件上传示例

Spring MVC提供了一种上传文件的简便方法, 它可以是图像或其他文件。让我们看一个使用Spring MVC上传文件的简单示例。

所需的Jar文件

要运行此示例, 你需要加载：

• Spring Core jar文件
• Spring Web jar文件
• commons-fileupload.jar和commons-io.jar文件

1)下载spring的所有jar文件, 包括core, web, aop, mvc, j2ee, remoting, oxm, jdbc, orm等。

2)下载commons-io.jar

3)下载commons-fileupload.jar

Spring MVC文件上传步骤(超出MVC)

1)添加commons-io和fileupload.jar文件

2)在spring-servlet.xml中添加CommonsMultipartResolver条目

<bean id="multipartResolver" 
class="org.springframework.web.multipart.commons.CommonsMultipartResolver"/>

3)创建表格以提交文件。方法名称必须为” post”, 并键入” multiple / form-data”。

<form action="savefile" method="post" enctype="multipart/form-data">
Select File: <input type="file" name="file"/>
<input type="submit" value="Upload File"/>
</form>

4)在Controller中使用CommonsMultipartFile类。

@RequestMapping(value="/savefile", method=RequestMethod.POST)
public ModelAndView upload(@RequestParam CommonsMultipartFile file, HttpSession session){
		String path=session.getServletContext().getRealPath("/");
		String filename=file.getOriginalFilename();
		
		System.out.println(path+" "+filename);
		try{
		byte barr[]=file.getBytes();
		
		BufferedOutputStream bout=new BufferedOutputStream(
                 new FileOutputStream(path+"/"+filename));
		bout.write(barr);
		bout.flush();
		bout.close();
		
		}catch(Exception e){System.out.println(e);}
		return new ModelAndView("upload-success", "filename", path+"/"+filename);
	}

5)在JSP中显示图像。

<h1>Upload Success</h1>
<img src="${filename}"/>

Spring MVC文件上传示例

创建图像目录

在你的项目中创建”图像”目录, 因为我们正在编写代码以将所有文件保存在” / images”目录中。

index.jsp

<a href="uploadform">Upload Image</a>

Emp.java

package com.srcmini;
import java.io.BufferedOutputStream;
import java.io.File;
import java.io.FileOutputStream;
import javax.servlet.ServletContext;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;
import org.apache.commons.fileupload.disk.DiskFileItemFactory;
import org.apache.commons.fileupload.servlet.ServletFileUpload;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.ModelAttribute;
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.commons.CommonsMultipartFile;
import org.springframework.web.servlet.ModelAndView;

@Controller
public class HelloController {
	private static final String UPLOAD_DIRECTORY ="/images";
	
	@RequestMapping("uploadform")
	public ModelAndView uploadForm(){
		return new ModelAndView("uploadform");	
	}
	
	@RequestMapping(value="savefile", method=RequestMethod.POST)
	public ModelAndView saveimage( @RequestParam CommonsMultipartFile file, HttpSession session) throws Exception{

	ServletContext context = session.getServletContext();
	String path = context.getRealPath(UPLOAD_DIRECTORY);
	String filename = file.getOriginalFilename();

	System.out.println(path+" "+filename);	    

	byte[] bytes = file.getBytes();
	BufferedOutputStream stream =new BufferedOutputStream(new FileOutputStream(
         new File(path + File.separator + filename)));
	stream.write(bytes);
	stream.flush();
	stream.close();
	     
	return new ModelAndView("uploadform", "filesuccess", "File successfully saved!");
	}
}

web.xml

<?xml version="1.0" encoding="UTF-8"?>
<web-app version="2.5" 
	xmlns="http://java.sun.com/xml/ns/javaee" 
	xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" 
	xsi:schemaLocation="http://java.sun.com/xml/ns/javaee 
	http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd">
 <servlet>
	<servlet-name>spring</servlet-name>
	<servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
	<load-on-startup>1</load-on-startup>
</servlet>
<servlet-mapping>
	<servlet-name>spring</servlet-name>
	<url-pattern>/</url-pattern>
</servlet-mapping>
</web-app>

spring-servlet.xml

在这里, 你需要为CommonsMultipartResolver创建一个bean。

<?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">  

<context:component-scan base-package="com.srcmini"></context:component-scan>

<bean class="org.springframework.web.servlet.view.InternalResourceViewResolver">
<property name="prefix" value="/WEB-INF/jsp/"></property>
<property name="suffix" value=".jsp"></property>
</bean>

<bean id="multipartResolver" 
class="org.springframework.web.multipart.commons.CommonsMultipartResolver"/>

</beans>

uploadform.jsp

这里的表单必须是method =” post”和enctype =” multipart / form-data”。

<%@taglib uri="http://www.springframework.org/tags/form" prefix="form"%>
 
<!DOCTYPE html>
<html>
 <head>
 <title>Image File Upload</title>
 </head>
 <body>
<h1>File Upload Example - srcmini</h1>

<h3 style="color:red">${filesuccess}</h3>
<form:form method="post" action="savefile" enctype="multipart/form-data">
<p><label for="image">Choose Image</label></p>
<p><input name="file" id="fileToUpload" type="file" /></p>
<p><input type="submit" value="Upload"></p>
</form:form>
</body>
</html>

输出

转到服务器控制台上打印的路径, 以查看上载的文件。

下载Spring MVC文件上传示例

我们已经在MyEclipse IDE中创建了该应用程序, 该应用程序已经提供了jar文件。如果你使用eclipse或其他IDE, 则需要为spring MVC加载jar文件。

下载此示例(使用MyEclipse开发)