jQuery Uploadify + Apache Fileupload异步上传文件示例
1、可以限制上传文件大小和类型，理论上任何类型的文件都可以上传（自己根据api配置即可）；
2、后台使用Apache commons-fileupload-1.3.1.jar作为上传工具包，本示例支持一次性多文件上传；
3、文件上传目录可以任意指定，请在web.xml中配置；
Uploadify api 详见http://www.uploadify.com/documentation/
FileUploadServlet
package com.xiaoxing.upload;
import java.io.File;
import java.io.IOException;
import java.io.PrintWriter;
import java.io.UnsupportedEncodingException;
import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.Iterator;
import java.util.List;
import java.util.UUID;
import javax.servlet.ServletException;
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.disk.DiskFileItemFactory;
import org.apache.commons.fileupload.servlet.ServletFileUpload;
/**
* <h1>Apache Fileupload文件上传（2014-5-3）</h1>
* <p>1、如果你对本示例感兴趣并想了解更多，欢迎加入Java私塾在线学习社区（329232140）</p>
* <p>2、针对这个例子小修小改便可移植到你的实际项目中。</p>
*/
public class FileUploadServlet extends HttpServlet {
private static final long serialVersionUID = 7579265950932321867L;
// 设置文件默认上传目录（如果你没有在web.xml中配置的话）
private String uploadDir = "c:/"; // 文件上传目录
private String tempUploadDir = "c:/"; // 文件临时存放目录（会话销毁后由监听器自动删除）
/*
* (non-Javadoc)
* @see javax.servlet.GenericServlet#init()
* 如果在web.xml中配置了文件上传目录则优先使用，判断文件目录是否存在，不存在就创建。
*/
@Override
public void init() throws ServletException {
// 获取本项目所在真实硬盘目录
String path = getClass().getProtectionDomain().getCodeSource().getLocation().getPath();
path = path.substring(0, path.indexOf("WEB-INF"));
// 判断目标是否存在，不存在就建立
String uploadDir = path.concat(this.getInitParameter("uploadDir"));
String tempUploadDir = path.concat(this.getInitParameter("tempUploadDir"));
File f_uploadDir = new File(uploadDir);
File f_tempUploadDir = new File(tempUploadDir);
if (!f_uploadDir.exists()) {
f_uploadDir.mkdirs();
}
if (!f_tempUploadDir.exists()) {
f_tempUploadDir.mkdirs();
}
// 给变量赋值
this.uploadDir = uploadDir;
this.tempUploadDir = tempUploadDir;
}
/*
* (non-Javadoc)
* @see javax.servlet.http.HttpServlet#doGet(javax.servlet.http.HttpServletRequest, javax.servlet.http.HttpServletResponse)
* 不接收get方式提交的数据，返回上传失败状态码。
*/
@Override
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
this.setResponse(response);
PrintWriter out = response.getWriter();
out.print("{\"error\":\"-1\""); // 非法提交方式
}
/*
* (non-Javadoc)
* @see javax.servlet.http.HttpServlet#doPost(javax.servlet.http.HttpServletRequest, javax.servlet.http.HttpServletResponse)
* 上传文件请求都是通常POST提交
*/
@Override
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
this.setResponse(response); // 设置响应类型，以便前端解析
PrintWriter out = response.getWriter();
String result = "";
try {
// 检查本次是否一个文件上传请求
boolean isMultipart = ServletFileUpload.isMultipartContent(request);
if (isMultipart) {
DiskFileItemFactory factory = new DiskFileItemFactory(); // 创建一个工厂基于磁盘的文件项
factory.setRepository(new File(tempUploadDir)); // 配置储存库（确保安全的临时位置时）
ServletFileUpload upload = new ServletFileUpload(factory); // 创建一个新的文件上传处理程序
upload.setSizeMax(1024 * 1024 * 100); // 设置总体要求尺寸限制（建议前后台分别设置，因为前后台用到了不同的插件）
List<FileItem> items = upload.parseRequest(request); // 解析请求
Iterator<FileItem> iter = items.iterator(); // 处理上传的项目
while (iter.hasNext()) { //如果是一次性上传多个文件，那这里会分别去保存
FileItem item = iter.next();
if (!item.isFormField()) { // 过滤表单里的非文件类型字段
if (!"".equals(item.getName())) { // 过滤非文件类型的input
String s_name = item.getName(); // 获得原始文件名
int position = s_name.lastIndexOf(".");
String s_fileType = s_name.substring(position, s_name.length()); // 获得文件后缀
String date = new SimpleDateFormat("yyyyMMdd").format(new Date());
String s = uploadDir.concat("/").concat(date).concat("/");
//这里按日期分目录保存文件
File sf = new File(s);
if (!sf.exists()) {
sf.mkdirs();
}
String s_filePath = s.concat(UUID.randomUUID().toString()).concat(s_fileType);
File path = new File(s_filePath);
item.write(path);
result += s_filePath.concat(",");
} else {
result = "";
break;
}
}
}
} else {
result = "";
}
String s_resultJSON = this.jointJSON(result); // 拼接返回前端JSON
out.print(s_resultJSON);
} catch (Exception e) {
e.printStackTrace();
} finally {
out.flush();
out.close();
}
}
/**
* 拼接JSON，将保存文件的文件名和日期目录返回给前端（前端可能需要这个路径完成其他表单操作，比如将文件路径存放到数据库）
* @param result JSON格式的字符串
* @return
* @throws UnsupportedEncodingException
*/
private String jointJSON (String result) throws UnsupportedEncodingException {
String str = "";
if(!"".equals(result)) {
String rs[] = result.split(",");
StringBuffer buffer = new StringBuffer("{\"rows\":[");
for (int i = 0; i < rs.length; i++) {
String s_tmpName = rs[i];
s_tmpName = s_tmpName.substring(uploadDir.length(), s_tmpName.length());
buffer.append("{\"name\":\"").append(s_tmpName).append("\"},");
}
str = buffer.toString();
str = str.substring(0, str.length() - 1).concat("]}");
} else {
str = "{\"error\":\"-2\""; //上传失败
}
return str;
}
/**
* 设置响应类型ContentType为"application/x-json"
* @param response
*/
private void setResponse(HttpServletResponse response) {
response.setCharacterEncoding("UTF-8");
response.setContentType("application/json;charset=UTF-8");
response.setHeader("cache-control", "no-cache");
}
}
test_upload.html
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>jQuery Uploadify + Apache Fileupload异步上传文件示例(2014-5-3)</title>
<link rel="stylesheet" type="text/css" href="/js/uploadify/uploadify.css">
<script src="/js/jquery-1.9.0.js"></script>
<script src="/js/uploadify/jquery.uploadify.min.js"></script>
<script type="text/javascript">
$(function() {
$('#fileupload').uploadify({
'method' : 'post',
'buttonText' : 'flash上传文件',
'fileSizeLimit' : '1024KB',
'fileTypeExts' : '*.gif; *.jpg; *.png',
'swf' : '/js/uploadify/uploadify.swf',
'uploader' : '/upload', //这是上传图片的路径，也就是我在web.xml里配置的servlet
'onUploadSuccess' : function(file, data, response) { //图片上传成功后返回数据在这里处理
var ary = eval("(" + data + ")").rows;
for(var i = 0; i < ary.length; i++) {
$("#J_div").append("<img style="margin: 3px auto 0px; padding: 0px 3px; outline: none; line-height: 25.2px; font-size: 14px; background: rgb(242, 246, 251); width: 640px; clear: both; border-top: 1px solid rgb(0, 153, 204); border-right: 1px solid rgb(0, 153, 204); border-left: 1px solid rgb(0, 153, 204); border-image: initial; border-bottom: none; font-family: tahoma, arial, "Microsoft YaHei";"> 复制代码代码如下:
<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://java.sun.com/xml/ns/javaee" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd" metadata-complete="true" version="3.0">
<welcome-file-list>
<welcome-file>test_upload.html</welcome-file>
</welcome-file-list>
<servlet>
<description>专门用来处理上传操作的servlet</description>
<servlet-name>FileUploadServlet</servlet-name>
<servlet-class>com.xiaoxing.upload.FileUploadServlet</servlet-class>
<init-param>
<description>文件存放的正式目录，可以自己配置</description>
<param-name>uploadDir</param-name>
<param-value>/upload/images/</param-value>
</init-param>
<init-param>
<description>文件存放的临时目录，可以自己配置，里的文件由下面配置的监听器自动删除。</description>
<param-name>tempUploadDir</param-name>
<param-value>/upload/temp</param-value>
</init-param>
</servlet>
<servlet-mapping>
<servlet-name>FileUploadServlet</servlet-name>
<url-pattern>/upload</url-pattern>
</servlet-mapping>
<listener>
<description>临时文件资源清理，工具包自带，不用我们来写</description>
<listener-class>org.apache.commons.fileupload.servlet.FileCleanerCleanup</listener-class>
</listener>
</web-app>