springmvc文件上传下载

注意：

1  get和post请求时，获取参数的方法是不一样的。

2  下载文件时，可能文件名中包含%28或者%29，出现这种情况是是urlEncoder的encode方法将小括号编码了，而在游览器端没有解码%28，所以下载的文件名出现了%28的符号。

这里是将%28替换为“（”，将%29 替换为“）”，即对小括号不进行编码

上传文件的方法

@Controller
@RequestMapping("/file")
public class FileController {

    @PostMapping("/upload")
    @ResponseBody
    public String upload(@RequestParam("file") MultipartFile file, HttpServletRequest request) {
        if (!file.isEmpty()) {
            Date date = new Date();
            SimpleDateFormat dateFormat = new SimpleDateFormat("yyyyMMddHHmmss_");
            String prefix = dateFormat.format(date);
            String saveFileName = prefix + file.getOriginalFilename();
            File saveFile = new File(request.getSession().getServletContext().getRealPath("/upload/") +"/" +saveFileName);
            if (!saveFile.getParentFile().exists()) {
                saveFile.getParentFile().mkdirs();
            }
            try {
                BufferedOutputStream out = new BufferedOutputStream(new FileOutputStream(saveFile));
                out.write(file.getBytes());
                out.flush();
                out.close();
                return "success";
            } catch (FileNotFoundException e) {
                e.printStackTrace();
                return "failure";
            } catch (IOException e) {
                e.printStackTrace();
                return "failure";
            }
        } else {
            return "failure";
        }
    }

}

下载文件和删除文件的方法

@Controller
@RequestMapping
public class DownloadFileController {

    @Autowired
    private ServletContext servletContext;

    @RequestMapping(value = "/testDownload", method = RequestMethod.GET)
    public void Download(HttpServletRequest req  , HttpServletResponse res) throws Exception {
        String fileName =     new String(req.getParameter("name").getBytes("ISO-8859-1"),"utf-8");
        String type =     new String(req.getParameter("type").getBytes("ISO-8859-1"),"utf-8");
        res.setHeader("content-type", "application/octet-stream");
        res.setContentType("application/octet-stream");
        res.setHeader("Content-Disposition", "attachment;filename=" + URLEncoder.encode(fileName, "utf-8").replaceAll("%28", "(").replaceAll("%29", ")"));
        byte[] buff = new byte[1024];
        BufferedInputStream bis = null;
        OutputStream os = null;
        try {
            os = res.getOutputStream();
            bis = new BufferedInputStream(new FileInputStream( new File(servletContext.getRealPath("/upload/") +"/"+type+"/"+fileName)));
            int i = bis.read(buff);
            while (i != -1) {
                os.write(buff, 0, buff.length);
                os.flush();
                i = bis.read(buff);
            }
        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            if (bis != null) {
                try {
                    bis.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
        }
        System.out.println("success");
    }
    
    @RequestMapping(value = "/delfile", method = RequestMethod.GET)
    public void delfile(HttpServletRequest req  , HttpServletResponse res) throws Exception {
        String fileName =     new String(req.getParameter("name").getBytes("ISO-8859-1"),"utf-8");
        String type =     new String(req.getParameter("type").getBytes("ISO-8859-1"),"utf-8");
        File file =  new File(servletContext.getRealPath("/upload/") +"/"+type+"/"+fileName);
        if (file.exists() && file.isFile()) {
            if (file.delete()) {
                System.out.println("删除单个文件" + fileName + "成功！");
                return ;
            } 
        }
    }
    

}

文件列表显示方法

@Controller
@RequestMapping
public class ToFileListController {

    @Autowired
    private ServletContext servletContext;

    @RequestMapping("/fileList/{type}")
    public String fileList(Model model, @PathVariable("type") String type) {

        ArrayList<String> list = new ArrayList<String>();
        ArrayList<String> files = getFiles(servletContext.getRealPath("/upload/" + type));

        for (int i = 0; i < files.size(); i++) {
            File tempFile = new File(files.get(i).trim());

            String fileName = tempFile.getName();
            list.add(fileName);
        }
        Collections.sort(list, new Comparator<String>() {
            @Override
            public int compare(String o1, String o2) {
                String newO1 = o1.substring(0, 14);
                String newO2 = o2.substring(0, 14);
                return -newO1.compareTo(newO2);
            }
        });
        model.addAttribute("files", list);
        if ("android".equals(type)) {
            return "fileList";
        }return "";
    }

    public static ArrayList<String> getFiles(String path) {
        ArrayList<String> files = new ArrayList<String>();
        File file = new File(path);
        File[] tempList = file.listFiles();

        for (int i = 0; i < tempList.length; i++) {
            if (tempList[i].isFile()) {
                files.add(tempList[i].toString());
            }
        }
        return files;
    }
}

前台html

<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<%@ taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c" %>
<html>
<head>
    <title>文件列表</title>
    <style type="text/css">
        a{
            text-decoration:none;
        }
        table , td ,th{

            border:1px solid black;
            border-collapse:collapse;/*细线表格，合并边框*/
        }
    </style>
    <script type="text/javascript" src="http://apps.bdimg.com/libs/jquery/1.6.4/jquery.js"></script>
</head>
<body>
<div style="margin-top: 20px"></div>
<table id="content" width="800" border="0" cellspacing="0" cellpadding="0">
    <c:forEach items="${files}" var="user"  varStatus="status">
        <tr align="center">
            <td height="40px"> ${status.index}</td>
            <td> ${user}</td>
            <td><a href="/testDownload?type=android&name=${user}">下载</a></td>
            <td><a href="javascript:void(0)" onclick='delfile("${user}");'>删除</a></td>
        </tr>
    </c:forEach>
</table>
<!-- js部分 -->
<script>
    function delfile(name){
        //alert(name);
        $.get("/delfile", {name:name,type:"android"},function(){
            window.location.reload();
        });
    }
</script>
</body>
</html>

设置springmvc的配置文件

    <bean id="multipartResolver"
        class="org.springframework.web.multipart.commons.CommonsMultipartResolver">
        <property name="defaultEncoding" value="utf-8"></property>
        <property name="maxUploadSize" value="5242440"></property>
    </bean>