springmvc+maven利用MultipartFile上传下载文件及一些技巧

最新推荐文章于 2025-07-01 17:04:55 发布

原创最新推荐文章于 2025-07-01 17:04:55 发布 · 7.6k 阅读

4 ·

CC 4.0 BY-SA版权

java 专栏收录该内容

14 篇文章

订阅专栏

本文介绍了如何在SpringMVC项目中结合Maven实现文件的上传和下载。在文件上传部分，讲解了在pom.xml中配置依赖、jsp页面的实现以及后台controller的处理。在文件下载部分，提到了jsp注意事项和控制器的实现，强调了参数值的简化以避免IE浏览器的400错误。

摘要生成于 C知道，由 DeepSeek-R1 满血版支持，前往体验 >

一，上传文件

1 在pom.xml中加入以下

		<dependency>
			<groupId>commons-io</groupId>
			<artifactId>commons-io</artifactId>
			<version>2.4</version>
		</dependency>
		<dependency>
			<groupId>commons-fileupload</groupId>
			<artifactId>commons-fileupload</artifactId>
			<version>1.3</version>
		</dependency>

2 在jsp上，由于上传插件本身都是汉字，为了设置自己想要的字眼可以隐藏它，通过两个input来实现。也可以实现多文件上传，只需要在MultipartFile下面继续添加input。

<form id="applyForm" name="applyForm" class="validateForm" enctype="multipart/form-data">
<!-- 一定加入 enctype="multipart/form-data"，相当于识别标志 -->
     <div  style="float:left" >
		 <input noValidate  type="button" value="<spring:message code="register.uploadLicense"/>" onclick="document.applyForm.picpath.click()"> 
		 <input noValidate  name="path" id="path" readonly>
	</div> <br>
	<div class="input-groups" id="MultipartFile">																	
		<input type="file" noValidate    class="form-input" size="5242880"  id="picpath" name="picpath" style="display:none;" onChange="tras()"
accept="image/jpg,image/jpeg,image/png,image/bmp,application/zip,application/x-rar-compressed,application/msword,application/vnd.openxmlformats-officedocument.wordprocessingml.document,application/vnd.ms-excel,application/vnd.openxmlformats-officedocument.spreadsheetml.sheet,application/vnd.ms-powerpoint,text/plain,application/pdf" >
	</div>

3，在js上，把文件放入myfiles里面

function tras(){
	//alert(vl);
	var pa = $("#picpath").val();
	//alert(pa);
	var ars = new Array();
	ars = pa.split("\\");
	var path = ars[ars.length-1];
	//alert(path);
	$("#path").val(path);

}
	/** *******企业资料上传 js********* */
	$("#MultipartFile input").change(function(e) {
		var name = $(this).attr("name");
		var max = 5;
		var value = $(this).val();
		if (value) {
			var file = $(this).get(0).files[0];
			var size = parseInt(file.size);
			var reg = new RegExp(
					"(.jpg|.jpeg|.png|.bmp|.doc|.docx|.xls|.xlsx|.ppt|.txt|.pdf|.zip|.rar)");
			var match_rel = reg.test(value);
			// var
			// index=value.indexOf(".jpg")>0||value.indexOf("")>0||value.indexOf("")>0||value.indexOf("")>0||value.indexOf("")>0||value.indexOf("")>0||value.indexOf("")>0||value.indexOf("")>0||value.indexOf("")>0||value.indexOf("")||value.indexOf("")||value.indexOf("")||value.indexOf("");
			console.log(match_rel);
			if (match_rel) {
				if (size > max * 1024 * 1024) {

					$(this).val("").removeAttr("name");
					
					$("#MultipartFile").after("<p class='errorEle'>"+i18n['accept5m']+"</p>");
				} else {
					$(this).attr("name", "myfiles");
				}
			} else {
				$(this).val("");
				
				$("#MultipartFile").after("<p class='errorEle'>"+i18n['specification']+"</p>");
			}

		} else {
			$(this).removeAttr("name");
			$(this).val("");
		}
		;

	})
//加入一个提交表单的ajax即可
$("#applyForm").ajaxSubmit({
								type : "post",
								url : ctx + "/user/register.shtml",
								dataType : "json",
								success : function(data) {
									
									if (data.state == '200') {
                                   }
}）

4，后台controller

	@RequestMapping("/register")
	public void register(User user, HttpServletRequest request, HttpServletResponse response,@RequestParam MultipartFile[] myfiles) throws Exception {
		Map<String, Object> map = new HashMap<>();
		try {
            String upload = FileUtil.upload(myfiles,dir, request);
			if ("true".equals(upload.split("=")[0])) {
				if (upload.length() > 6) {
					path = upload.split("[=]")[1];
					String[] split = path.split("[+]");
					switch (split.length) {
					case 1:
						user.setLicense(split[0]);
						break;
					default:
						break;
					}
				}
			} else if("empty".equals(upload.split("=")[0])) {
				// 打印错误信息{文件上传失败}
				map.put("state", "30119");
				map.put("msg", wcu.getValue("code.30119", request));
				HtmlUtil.writerJson(response, map);
				return;
			}
          } catch (Exception e) {
			e.printStackTrace();
			map.put("state", CodeConst.EXCEPTION_516.getState());
			map.put("msg", wcu.getValue("code.516", request));
			HtmlUtil.writerJson(response, map);
		}
	}

FileUtil.java

package com.apk.openUser.utils;

import java.io.BufferedInputStream;
import java.io.BufferedOutputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.InputStream;
import java.io.OutputStream;
import java.net.URLEncoder;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import org.apache.commons.io.FileUtils;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.web.multipart.MultipartFile;

import sun.misc.BASE64Encoder;


public class FileUtil {
	private final static Logger logger = LoggerFactory
			.getLogger(FileUtil.class);
	private final static String file_path = PropertyUtil.getProperty("file_path");
	/**
	 * 多文件上传
	 * @param myfiles
	 * @param request
	 * @return
	 * @throws Exception
	 */
	public static String upload(MultipartFile[] myfiles,String dir,HttpServletRequest request) throws Exception{
		String msg = "true";
		StringBuffer path = new StringBuffer();
		if (myfiles==null||myfiles.length==0) {
			msg="empty=文件不能为空";
		}
		System.out.println(myfiles.length);
		for (MultipartFile myfile : myfiles) {
			System.out.println(myfile);
			if (myfile.isEmpty()) {
				msg = "empty=文件不能为空";

			} else {
				String fileName = myfile.getOriginalFilename();
				String lastName = fileName.substring(fileName.lastIndexOf(".") + 1,fileName.length());
				if(NetCheckFieldsUtil.isRight(lastName)){
					// 如果用的是Tomcat服务器，则文件会上传到\\%TOMCAT_HOME%\\webapps\\YourWebProject\\WEB-INF\\upload\\文件夹中
					/*String realPath = request.getSession().getServletContext()
							.getRealPath("/WEB-INF/myfiles");*/
					// 这里不必处理IO流关闭的问题，因为FileUtils.copyInputStreamToFile()方法内部会自动把用到的IO流关掉，我是看它的源码才知道的
					
					//String file_path1 = file_path+File.separator+dir;
					
					File folder = new File(file_path);
					
					if (!folder.exists() && !folder.isDirectory()) {
						logger.info("文件夹路径不存在，创建路径:" + folder);
						folder.mkdirs();
					}
					//用base加密防止Linux乱码
					BASE64Encoder encoder = new BASE64Encoder();//用base防止在Linux下中文乱码
					String fileN = encoder.encode((dir+fileName).getBytes());
					System.out.println("fileNames:"+fileN);
					FileUtils.copyInputStreamToFile(myfile.getInputStream(),
							new File(file_path, fileN));
					//数据保存为 myfilesHydrangeas.jpg,D:\ztyq-open\apply-open-web\src\main\webapp\WEB-INF\myfiles\Hydrangeas.jpg
					//path.append(fileName).append(",").append(UUID.randomUUID().toString().replace("-", "")).append(".").append(lastName).append("+");
					path.append(fileName).append("+");


				}else{
					logger.error("文件格式不支持请重新选择");
					msg = "401=文件格式不支持请重新选择";

				}
			}

		}
		msg = msg + "=" + path.toString();
		System.out.println("MSG:::"+msg);
		return msg;
	}
	/**
	 * 下载文件
	 * @param filepath
	 * @param response
	 * @param request
	 * @throws Exception
	 */
	public static void downloadPath(String dir,String fileName,HttpServletResponse response,HttpServletRequest request) throws Exception {
		BASE64Encoder encoder = new BASE64Encoder();
		String fileN = encoder.encode((dir+fileName).getBytes());
		File file = new File(file_path+File.separator+fileN);//File.separator是自动识别系统路径中斜杠的写法。
		InputStream inputStream;
		inputStream = new BufferedInputStream(new FileInputStream(file));
		byte[] buffer = new byte[inputStream.available()];
		inputStream.read(buffer);
		inputStream.close();
		response.reset();
		String fileNames="";
		System.out.println(request.getHeader("User-Agent").toLowerCase());
		//System.out.println(request.getHeader("User-Agent").toUpperCase());
		String agent = request.getHeader("User-Agent").toLowerCase();
		if (agent.indexOf("msie") > 0||agent.indexOf("edge")>0||(agent.indexOf("like gecko")>0&&agent.indexOf("chrome")==-1)) {  
				fileNames = URLEncoder.encode(fileName, "UTF-8");// IE浏览器  
		}else{  
				fileNames = new String(fileName.getBytes("UTF-8"), "ISO8859-1");// 谷歌  
		}
				
		System.out.println(fileNames);
		//System.out.println(new String(filenames.getBytes("UTF-8"), "ISO-8859-1"));
		// 先去掉文件名称中的空格,然后转换编码格式为utf-8,保证不出现乱码,这个文件名称用于浏览器的下载框中自动显示的文件名
		response.addHeader("Content-Disposition", "attachment;filename=" + fileNames);
		response.addHeader("Content-Length", "" + file.length());
		OutputStream os = new BufferedOutputStream(response.getOutputStream());
		response.setContentType("application/octet-stream");
		os.write(buffer);// 输出文件
		os.flush();
		os.close();
	}

}

二，下载文件

1，jsp上，注意传的参数值尽量简单是个数字不含有中文，如果有中文IE浏览器上直接报400.

<a href="${ ctx }/auditor/downloadFile.do?id=${session_user.id}">

2，controller

    @RequestMapping("/downloadFile")
    public void downloadFile(String id, HttpServletResponse response, HttpServletRequest request) throws Exception {

        
        int id1 = Integer.parseInt(id);
        User user = userService.queryUserById(id1);
        String fileName = user.getLicense();

        response.setCharacterEncoding("utf-8");
        response.setContentType("application/octet-stream;charset=utf-8");
        
        response.setHeader("Content-Disposition", "attachment;fileName=" + fileName);

        System.out.println("fileName:"+fileName);

        FileUtil.downloadPath(user.getUsername(),fileName, response, request);
    }
    
}