上传

<%@ page language="java" contentType="text/html; charset=UTF-8" pageEncoding="UTF-8"%>
<%@ page import="java.util.*,java.io.*" %>
<%@ page import="java.text.SimpleDateFormat" %>
<%@ page import="org.apache.commons.fileupload.*" %>
<%@ page import="org.apache.commons.fileupload.disk.*" %>
<%@ page import="org.apache.commons.fileupload.servlet.*" %>
<%@ page import="org.json.simple.*" %>
<%

/**
 * KindEditor JSP
 * 
 * 本JSP程序是演示程序，建议不要直接在实际项目中使用。
 * 如果您确定直接使用本程序，使用之前请仔细确认相关安全设置。
 * 
 */

//文件保存目录路径
String savePath = pageContext.getServletContext().getRealPath("/") + "upload/";

//文件保存目录URL
String saveUrl  = request.getContextPath() + "/upload/";

//定义允许上传的文件扩展名
HashMap<String, String> extMap = new HashMap<String, String>();
extMap.put("image", "gif,jpg,jpeg,png,bmp");
extMap.put("flash", "swf,flv");
extMap.put("media", "swf,flv,mp3,wav,wma,wmv,mid,avi,mpg,asf,rm,rmvb");
extMap.put("file", "doc,docx,xls,xlsx,ppt,htm,html,txt,zip,rar,gz,bz2");

//最大文件大小
long maxSize = 1000000;

response.setContentType("text/html; charset=UTF-8");

if(!ServletFileUpload.isMultipartContent(request)){
    out.println(getError("请选择文件。"));
    return;
}
//检查目录
File uploadDir = new File(savePath);
if(!uploadDir.isDirectory()){
    out.println(getError("上传目录不存在。"));
    return;
}
//检查目录写权限
if(!uploadDir.canWrite()){
    out.println(getError("上传目录没有写权限。"));
    return;
}

String dirName = request.getParameter("dir");
if (dirName == null) {
    dirName = "image";
}
if(!extMap.containsKey(dirName)){
    out.println(getError("目录名不正确。"));
    return;
}
//创建文件夹
savePath += dirName + "/";
saveUrl += dirName + "/";
File saveDirFile = new File(savePath);
if (!saveDirFile.exists()) {
    saveDirFile.mkdirs();
}
SimpleDateFormat sdf = new SimpleDateFormat("yyyyMMdd");
String ymd = sdf.format(new Date());
savePath += ymd + "/";
saveUrl += ymd + "/";
File dirFile = new File(savePath);
if (!dirFile.exists()) {
    dirFile.mkdirs();
}

FileItemFactory factory = new DiskFileItemFactory();
ServletFileUpload upload = new ServletFileUpload(factory);
upload.setHeaderEncoding("UTF-8");
List items = upload.parseRequest(request);
Iterator itr = items.iterator();
while (itr.hasNext()) {
    FileItem item = (FileItem) itr.next();
    String fileName = item.getName();
    long fileSize = item.getSize();
    if (!item.isFormField()) {
        //检查文件大小
        if(item.getSize() > maxSize){
            out.println(getError("上传文件大小超过限制。"));
            return;
        }
        //检查扩展名
        String fileExt = fileName.substring(fileName.lastIndexOf(".") + 1).toLowerCase();
        if(!Arrays.<String>asList(extMap.get(dirName).split(",")).contains(fileExt)){
            out.println(getError("上传文件扩展名是不允许的扩展名。
只允许" + extMap.get(dirName) + "格式。"));
            return;
        }

        SimpleDateFormat df = new SimpleDateFormat("yyyyMMddHHmmss");
        String newFileName = df.format(new Date()) + "_" + new Random().nextInt(1000) + "." + fileExt;
        try{
            File uploadedFile = new File(savePath, newFileName);
            item.write(uploadedFile);
        }catch(Exception e){
            out.println(getError("上传文件失败。"));
            return;
        }

        JSONObject obj = new JSONObject();
        obj.put("error", 0);
        obj.put("url", saveUrl + newFileName);
        out.println(obj.toJSONString());
    }
}
%>
<%!
private String getError(String message) {
    JSONObject obj = new JSONObject();
    obj.put("error", 1);
    obj.put("message", message);
    return obj.toJSONString();
}
%>