最近使用jeesite框架，需要上传功能，机缘巧合使用了Jquery File Upload插件（以下简称JFU）。
首先下载JFU解压缩后里面自带demo，以jquery-ui.html这个demo为例，我经过测试上传发现上传时的进度条有明显缺陷这里我将他隐藏。将无用处的内容删除，注意demo里有部分CSS/JS链接指向外部网站这里我将它们统统下载至本地，令修改了“template-download”模板增加一个隐藏的input用于记录文件id。代码如下所示：
<!DOCTYPE HTML>
<html lang="zh">
<head>
<!-- Force latest IE rendering engine or ChromeFrame if installed -->
<!--[if IE]>
<meta http-equiv="X-UA-Compatible" content="IE=edge,chrome=1">
<![endif]-->
<meta charset="utf-8">
<title>上传测试</title>
<meta name="description" content="File Upload widget with multiple file selection, drag&drop support, progress bars, validation and preview images, audio and video for jQuery. Supports cross-domain, chunked and resumable file uploads and client-side image resizing. Works with any server-side platform (PHP, Python, Ruby on Rails, Java, Node.js, Go etc.) that supports standard HTML form file uploads.">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<!-- jQuery UI styles -->
<link rel="stylesheet" href="css/jquery-ui2.css" id="theme">
<!-- Demo styles -->
<!--[if lte IE 8]>
<link rel="stylesheet" href="css/demo-ie8.css">
<![endif]-->
<style>
/* Adjust the jQuery UI widget font-size: */
.ui-widget {
font-size: 0.95em;
}
</style>
<!-- blueimp Gallery styles -->
<link rel="stylesheet" href="css/blueimp-gallery.min.css">
<!-- CSS to style the file input field as button and adjust the Bootstrap progress bars -->
<!-- Demo styles -->
<link rel="stylesheet" href="css/demo.css">
<link rel="stylesheet" href="css/jquery.fileupload.css">
<link rel="stylesheet" href="css/jquery.fileupload-ui.css">
<!-- CSS adjustments for browsers with JavaScript disabled -->
<noscript><link rel="stylesheet" href="css/jquery.fileupload-noscript.css"></noscript>
<noscript><link rel="stylesheet" href="css/jquery.fileupload-ui-noscript.css"></noscript>
</head>
<body>
<!-- The file upload form used as target for the file upload widget -->
<form id="fileupload" action="//jquery-file-upload.appspot.com/" method="POST" enctype="multipart/form-data">
<!-- The fileupload-buttonbar contains buttons to add/delete files and start/cancel the upload -->
<div class="fileupload-buttonbar">
<div class="fileupload-buttons">
<!-- The fileinput-button span is used to style the file input field as button -->
<span class="fileinput-button">
<span>添加文件</span>
<input type="file" name="files[]" multiple>
</span>
<button type="submit" class="start">开始上传</button>
<button type="reset" class="cancel">取消上传</button>
<button type="button" class="delete">删除</button>
<input type="checkbox" class="toggle">
<!-- The global file processing state -->
<span class="fileupload-process"></span>
</div>
<!-- The global progress state -->
<div class="fileupload-progress fade" style="display:none">
<!-- The global progress bar -->
<div class="progress" role="progressbar" aria-valuemin="0" aria-valuemax="100"></div>
<!-- The extended global progress state -->
<div class="progress-extended"> </div>
</div>
</div>
<!-- The table listing the files available for upload/download -->
<table role="presentation"><tbody class="files">
<tr class="template-download fade" style="">
<td>
<span class="preview">
</span>
</td>
<td>
<p class="name">
<a href="upload?getfile=load-image.all.min.js" title="load-image.all.min.js" download="load-image.all.min.js">回显测试</a>
<input name="files" value="38c2ec65-841e-4cbf-a34b-f30a026773ec" type="hidden">
</p>
</td>
<td>
<span class="size">17.77 KB</span>
</td>
<td>
<button class="delete ui-button ui-widget ui-state-default ui-corner-all ui-button-text-icon-primary" data-type="" data-url="" role="button"><span class="ui-button-icon-primary ui-icon ui-icon-trash"></span><span class="ui-button-text">Delete</span></button>
<input name="delete" value="1" class="toggle" type="checkbox">
</td>
</tr>
<tr class="template-download fade" style="">
<td>
<span class="preview">
</span>
</td>
<td>
<p class="name">
<a href="upload?getfile=HTML2JS.exe" title="HTML2JS.exe" download="HTML2JS.exe">HTML2JS.exe</a>
<input name="files" value="d44bf3db-d79c-480e-8e04-b15847863c27" type="hidden">
</p>
</td>
<td>
<span class="size">11.78 KB</span>
</td>
<td>
<button class="delete ui-button ui-widget ui-state-default ui-corner-all ui-button-text-icon-primary" data-type="" data-url="" role="button"><span class="ui-button-icon-primary ui-icon ui-icon-trash"></span><span class="ui-button-text">Delete</span></button>
<input name="delete" value="1" class="toggle" type="checkbox">
</td>
</tr>
</tbody></table>
</form>
<!-- The template to display files available for upload -->
<script id="template-upload" type="text/x-tmpl">
{% for (var i=0, file; file=o.files[i]; i++) { %}
<tr class="template-upload fade">
<td>
<span class="preview"></span>
</td>
<td>
<p class="name">{%=file.name%}</p>
<strong class="error"></strong>
</td>
<td>
<p class="size">Processing...</p>
<div class="progress" style="display:none;"></div>
</td>
<td>
{% if (!i && !o.options.autoUpload) { %}
<button class="start" disabled>Start</button>
{% } %}
{% if (!i) { %}
<button class="cancel">Cancel</button>
{% } %}
</td>
</tr>
{% } %}
</script>
<!-- The template to display files available for download -->
<script id="template-download" type="text/x-tmpl">
{% for (var i=0, file; file=o.files[i]; i++) { %}
<tr class="template-download fade">
<td>
<span class="preview">
{% if (file.thumbnailUrl) { %}
<a href="{%=file.url%}" title="{%=file.name%}" download="{%=file.name%}" data-gallery><img src="{%=file.thumbnailUrl%}"></a>
{% } %}
</span>
</td>
<td>
<p class="name">
<a href="{%=file.url%}" title="{%=file.name%}" download="{%=file.name%}" {%=file.thumbnailUrl?'data-gallery':''%}>{%=file.name%}</a>
<input type="hidden" name="files" value="{%=file.fileid%}" >
</p>
{% if (file.error) { %}
<div><span class="error">Error</span> {%=file.error%}</div>
{% } %}
</td>
<td>
<span class="size">{%=o.formatFileSize(file.size)%}</span>
</td>
<td>
<button class="delete" data-type="{%=file.deleteType%}" data-url="{%=file.deleteUrl%}"{% if (file.deleteWithCredentials) { %} data-xhr-fields='{"withCredentials":true}'{% } %}>Delete</button>
<input type="checkbox" name="delete" value="1" class="toggle">
</td>
</tr>
{% } %}
</script>
<script src="../bootstrap3/js/jquery-1.11.3.min.js"></script>
<script src="js/jquery-ui.js"></script>
<!-- The Templates plugin is included to render the upload/download listings -->
<script src="js/tmpl.min.js"></script>
<!-- The Load Image plugin is included for the preview images and image resizing functionality -->
<script src="js/load-image.all.min.js"></script>
<!-- The Canvas to Blob plugin is included for image resizing functionality -->
<script src="js/canvas-to-blob.min.js"></script>
<!-- blueimp Gallery script -->
<script src="js/jquery.blueimp-gallery.min.js"></script>
<!-- The Iframe Transport is required for browsers without support for XHR file uploads -->
<script src="js/jquery.iframe-transport.js"></script>
<!-- The basic File Upload plugin -->
<script src="js/jquery.fileupload.js"></script>
<!-- The File Upload processing plugin -->
<script src="js/jquery.fileupload-process.js"></script>
<!-- The File Upload image preview & resize plugin -->
<script src="js/jquery.fileupload-image.js"></script>
<!-- The File Upload audio preview plugin -->
<script src="js/jquery.fileupload-audio.js"></script>
<!-- The File Upload video preview plugin -->
<script src="js/jquery.fileupload-video.js"></script>
<!-- The File Upload validation plugin -->
<script src="js/jquery.fileupload-validate.js"></script>
<!-- The File Upload user interface plugin -->
<script src="js/jquery.fileupload-ui.js"></script>
<!-- The File Upload jQuery UI plugin -->
<script src="js/jquery.fileupload-jquery-ui.js"></script>
<!-- The main application script -->
<script src="js/main.js"></script>
<!-- The XDomainRequest Transport is included for cross-domain file deletion for IE 8 and IE 9 -->
<!--[if (gte IE 8)&(lt IE 10)]>
<script src="js/cors/jquery.xdr-transport.js"></script>
<![endif]-->
</body>
</html>
修改jquery.fileupload-ui.js里面的getFilesFromResponse方法，修改了返回值为return data.result，这里非常关键。
最后servlet代码如下所示：
package com.thinkgem.jeesite.JFupload.web;
import java.awt.image.BufferedImage;
import java.io.*;
import java.util.List;
import java.util.UUID;
import javax.imageio.ImageIO;
import javax.servlet.ServletConfig;
import javax.servlet.ServletException;
import javax.servlet.ServletOutputStream;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.apache.commons.fileupload.FileItem;
import org.apache.commons.fileupload.FileUploadException;
import org.apache.commons.fileupload.disk.DiskFileItemFactory;
import org.apache.commons.fileupload.servlet.ServletFileUpload;
import org.imgscalr.Scalr;
import org.json.JSONArray;
import org.json.JSONObject;
public class UploadServlet extends HttpServlet {
// private static final long serialVersionUID = 1L;
private File fileUploadPath;
@Override
public void init(ServletConfig config) {
String path = config.getServletContext().getRealPath("/");
fileUploadPath = new File(path+config.getInitParameter("upload_path"));
}
/**
* @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
*
*/
@Override
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
if (request.getParameter("getfile") != null
&& !request.getParameter("getfile").isEmpty()) {
File file = new File(fileUploadPath,
request.getParameter("getfile"));
if (file.exists()) {
int bytes = 0;
ServletOutputStream op = response.getOutputStream();
response.setContentType(getMimeType(file));
response.setContentLength((int) file.length());
response.setHeader( "Content-Disposition", "inline; filename=\"" + file.getName() + "\"" );
byte[] bbuf = new byte[1024];
DataInputStream in = new DataInputStream(new FileInputStream(file));
while ((in != null) && ((bytes = in.read(bbuf)) != -1)) {
op.write(bbuf, 0, bytes);
}
in.close();
op.flush();
op.close();
}
} else if (request.getParameter("delfile") != null && !request.getParameter("delfile").isEmpty()) {
File file = new File(fileUploadPath, request.getParameter("delfile"));
if (file.exists()) {
file.delete(); // TODO:check and report success
}
} else if (request.getParameter("getthumb") != null && !request.getParameter("getthumb").isEmpty()) {
File file = new File(fileUploadPath, request.getParameter("getthumb"));
if (file.exists()) {
String mimetype = getMimeType(file);
if (mimetype.endsWith("png") || mimetype.endsWith("jpeg") || mimetype.endsWith("gif")) {
BufferedImage im = ImageIO.read(file);
if (im != null) {
BufferedImage thumb = Scalr.resize(im, 75);
ByteArrayOutputStream os = new ByteArrayOutputStream();
if (mimetype.endsWith("png")) {
ImageIO.write(thumb, "PNG" , os);
response.setContentType("image/png");
} else if (mimetype.endsWith("jpeg")) {
ImageIO.write(thumb, "jpg" , os);
response.setContentType("image/jpeg");
} else {
ImageIO.write(thumb, "GIF" , os);
response.setContentType("image/gif");
}
ServletOutputStream srvos = response.getOutputStream();
response.setContentLength(os.size());
response.setHeader( "Content-Disposition", "inline; filename=\"" + file.getName() + "\"" );
os.writeTo(srvos);
srvos.flush();
srvos.close();
}
}
} // TODO: check and report success
} else {
PrintWriter writer = response.getWriter();
writer.write("call POST with multipart form data");
}
}
/**
* @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
*
*/
@SuppressWarnings("unchecked")
@Override
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
if (!ServletFileUpload.isMultipartContent(request)) {
throw new IllegalArgumentException("Request is not multipart, please 'multipart/form-data' enctype for your form.");
}
ServletFileUpload uploadHandler = new ServletFileUpload(new DiskFileItemFactory());
PrintWriter writer = response.getWriter();
response.setContentType("text/html;charset=utf-8");
JSONArray json = new JSONArray();
try {
List<FileItem> items = uploadHandler.parseRequest(request);
for (FileItem item : items) {
if (!item.isFormField()) {
File file = new File(fileUploadPath, item.getName());
item.write(file);
JSONObject jsono = new JSONObject();
jsono.put("name", item.getName());
jsono.put("size", item.getSize());
jsono.put("url", "upload?getfile=" + item.getName());
jsono.put("thumbnail_url", "upload?getthumb=" + item.getName());
jsono.put("delete_url", "upload?delfile=" + item.getName());
jsono.put("delete_type", "GET");
jsono.put("fileid", UUID.randomUUID().toString());
json.put(jsono);
}
}
} catch (FileUploadException e) {
throw new RuntimeException(e);
} catch (Exception e) {
throw new RuntimeException(e);
} finally {
System.out.println(json.toString());
writer.write(json.toString());
writer.close();
}
}
private String getMimeType(File file) {
String mimetype = "";
if (file.exists()) {
// URLConnection uc = new URL("file://" + file.getAbsolutePath()).openConnection();
// String mimetype = uc.getContentType();
// MimetypesFIleTypeMap gives PNG as application/octet-stream, but it seems so does URLConnection
// have to make dirty workaround
if (getSuffix(file.getName()).equalsIgnoreCase("png")) {
mimetype = "image/png";
} else {
javax.activation.MimetypesFileTypeMap mtMap = new javax.activation.MimetypesFileTypeMap();
mimetype = mtMap.getContentType(file);
}
}
System.out.println("mimetype: " + mimetype);
return mimetype;
}
private String getSuffix(String filename) {
String suffix = "";
int pos = filename.lastIndexOf('.');
if (pos > 0 && pos < filename.length() - 1) {
suffix = filename.substring(pos + 1);
}
System.out.println("suffix: " + suffix);
return suffix;
}
}