项目中多处用到文件批量上传功能，今天正好攻克了此问题。在此写出来，以便日后借鉴。
首先，以下架构下的批量文件上传可能会失败或者不会成功：
1.androidclient+springMVC服务端：服务端採用org.springframework.web.multipart.MultipartHttpServletRequest作为批量上传接收类。这种搭配下的批量文件上传会失败。终于服务端仅仅会接受到一个文件。即仅仅会接受到第一个文件。可能由于MultipartHttpServletRequest对servlet原本的HttpServletRequest类进行封装，导致批量上传有问题。
2.androidclient+strutsMVC服务端：这种搭配下的多文件上传。本人没有亲自尝试，不做评论。假设有网友採用此种方式上传失败的。原因可能同1。
接下来说明上传成功的方案： 採用androidclient+Servlet（HttpServletRequest）进行文件上传。 Servlet端代码例如以下：
DiskFileItemFactory factory = new DiskFileItemFactory(); ServletFileUpload upload = new ServletFileUpload(factory); try { List items = upload.parseRequest(request); Iterator itr = items.iterator(); while (itr.hasNext()) { FileItem item = (FileItem) itr.next(); if (item.isFormField()) { System.out.println("表单參数名:" + item.getFieldName() + "，表单參数值:" + item.getString("UTF-8")); } else { if (item.getName() != null && !item.getName().equals("")) { System.out.println("上传文件的大小:" + item.getSize()); System.out.println("上传文件的类型:" + item.getContentType()); // item.getName()返回上传文件在client的完整路径名称 System.out.println("上传文件的名称:" + item.getName()); File tempFile = new File(item.getName()); // 上传文件的保存路径 File file = new File(sc.getRealPath("/") + savePath, tempFile.getName()); item.write(file); request.setAttribute("upload.message", "上传文件成功！"); } else { request.setAttribute("upload.message", "没有选择上传文件！"); } } } } catch (FileUploadException e) { e.printStackTrace(); } catch (Exception e) { e.printStackTrace(); request.setAttribute("upload.message", "上传文件失败！
"); } request.getRequestDispatcher("/uploadResult.jsp").forward(request, response);
android端代码例如以下：
public class SocketHttpRequester { /** *多文件上传 * 直接通过HTTP协议提交数据到server,实现如以下表单提交功能: * <FORM METHOD=POST ACTION="http://192.168.1.101:8083/upload/servlet/UploadServlet" enctype="multipart/form-data"> <INPUT TYPE="text" NAME="name"> <INPUT TYPE="text" NAME="id"> <input type="file" name="imagefile"/> <input type="file" name="zip"/> </FORM> * @param path 上传路径(注：避免使用localhost或127.0.0.1这种路径測试。由于它会指向手机模拟器，你能够使用http://www.iteye.cn或http://192.168.1.101:8083这种路径測试) * @param params 请求參数 key为參数名,value为參数值 * @param file 上传文件 */ public static boolean post(String path, Map<String, String> params, FormFile[] files) throws Exception{ final String BOUNDARY = "---------------------------7da2137580612"; //数据分隔线 final String endline = "--" + BOUNDARY + "--\r\n";//数据结束标志 int fileDataLength = 0; for(FormFile uploadFile : files){//得到文件类型数据的总长度 StringBuilder fileExplain = new StringBuilder(); fileExplain.append("--"); fileExplain.append(BOUNDARY); fileExplain.append("\r\n"); fileExplain.append("Content-Disposition: form-data;name=\""+ uploadFile.getParameterName()+"\";filename=\""+ uploadFile.getFilname() + "\"\r\n"); fileExplain.append("Content-Type: "+ uploadFile.getContentType()+"\r\n\r\n"); fileExplain.append("\r\n"); fileDataLength += fileExplain.length(); if(uploadFile.getInStream()!=null){ fileDataLength += uploadFile.getFile().length(); }else{ fileDataLength += uploadFile.getData().length; } } StringBuilder textEntity = new StringBuilder(); for (Map.Entry<String, String> entry : params.entrySet()) {//构造文本类型參数的实体数据 textEntity.append("--"); textEntity.append(BOUNDARY); textEntity.append("\r\n"); textEntity.append("Content-Disposition: form-data; name=\""+ entry.getKey() + "\"\r\n\r\n"); textEntity.append(entry.getValue()); textEntity.append("\r\n"); } //计算传输给server的实体数据总长度 int dataLength = textEntity.toString().getBytes().length + fileDataLength + endline.getBytes().length; URL url = new URL(path); int port = url.getPort()==-1 ?
80 : url.getPort(); Socket socket = new Socket(InetAddress.getByName(url.getHost()), port); OutputStream outStream = socket.getOutputStream(); //以下完毕HTTP请求头的发送 String requestmethod = "POST "+ url.getPath()+" HTTP/1.1\r\n"; outStream.write(requestmethod.getBytes()); String accept = "Accept: image/gif, image/jpeg, image/pjpeg, image/pjpeg, application/x-shockwave-flash, application/xaml+xml, application/vnd.ms-xpsdocument, application/x-ms-xbap, application/x-ms-application, application/vnd.ms-excel, application/vnd.ms-powerpoint, application/msword, */*\r\n"; outStream.write(accept.getBytes()); String language = "Accept-Language: zh-CN\r\n"; outStream.write(language.getBytes()); String contenttype = "Content-Type: multipart/form-data; boundary="+ BOUNDARY+ "\r\n"; outStream.write(contenttype.getBytes()); String contentlength = "Content-Length: "+ dataLength + "\r\n"; outStream.write(contentlength.getBytes()); String alive = "Connection: Keep-Alive\r\n"; outStream.write(alive.getBytes()); String host = "Host: "+ url.getHost() +":"+ port +"\r\n"; outStream.write(host.getBytes()); //写完HTTP请求头后依据HTTP协议再写一个回车换行 outStream.write("\r\n".getBytes()); //把全部文本类型的实体数据发送出来 outStream.write(textEntity.toString().getBytes()); //把全部文件类型的实体数据发送出来 for(FormFile uploadFile : files){ StringBuilder fileEntity = new StringBuilder(); fileEntity.append("--"); fileEntity.append(BOUNDARY); fileEntity.append("\r\n"); fileEntity.append("Content-Disposition: form-data;name=\""+ uploadFile.getParameterName()+"\";filename=\""+ uploadFile.getFilname() + "\"\r\n"); fileEntity.append("Content-Type: "+ uploadFile.getContentType()+"\r\n\r\n"); outStream.write(fileEntity.toString().getBytes()); if(uploadFile.getInStream()!=null){ byte[] buffer = new byte[1024]; int len = 0; while((len = uploadFile.getInStream().read(buffer, 0, 1024))!=-1){ outStream.write(buffer, 0, len); } uploadFile.getInStream().close(); }else{ outStream.write(uploadFile.getData(), 0, uploadFile.getData().length); } outStream.write("\r\n".getBytes()); } //以下发送数据结束标志。表示数据已经结束 outStream.write(endline.getBytes()); BufferedReader reader = new BufferedReader(new InputStreamReader(socket.getInputStream())); if(reader.readLine().indexOf("200")==-1){//读取webserver返回的数据，推断请求码是否为200。假设不是200，代表请求失败 return false; } outStream.flush(); outStream.close(); reader.close(); socket.close(); return true; } /** *单文件上传 * 提交数据到server * @param path 上传路径(注：避免使用localhost或127.0.0.1这种路径測试，由于它会指向手机模拟器，你能够使用http://www.itcast.cn或http://192.168.1.10:8080这种路径測试) * @param params 请求參数 key为參数名,value为參数值 * @param file 上传文件 */ public static boolean post(String path, Map<String, String> params, FormFile file) throws Exception{ return post(path, params, new FormFile[]{file}); } }
public class FormFile {
/* 上传文件的数据 */
private byte[] data;
private InputStream inStream;
private File file;
private int fileSize;
/* 文件名 */
private String filname;
/* 请求參数名称*/
private String parameterName;
/* 内容类型 */
private String contentType = "application/octet-stream";
public FormFile(String filname, byte[] data, String parameterName, String contentType) {
this.data = data;
this.filname = filname;
this.parameterName = parameterName;
if(contentType!=null) this.contentType = contentType;
}
public FormFile(String filname, File file, String parameterName, String contentType) {
this.filname = filname;
this.parameterName = parameterName;
this.file = file;
try {
this.inStream = new FileInputStream(file);
} catch (FileNotFoundException e) {
e.printStackTrace();
}
if(contentType!=null) this.contentType = contentType;
}
public FormFile(InputStream inStream, int fileSize, String filname,
String parameterName, String contentType) {
super();
this.inStream = inStream;
this.fileSize = fileSize;
this.filname = filname;
this.parameterName = parameterName;
this.contentType = contentType;
}
public int getFileSize() {
return fileSize;
}
public File getFile() {
return file;
}
public InputStream getInStream() {
return inStream;
}
public byte[] getData() {
return data;
}
public String getFilname() {
return filname;
}
public void setFilname(String filname) {
this.filname = filname;
}
public String getParameterName() {
return parameterName;
}
public void setParameterName(String parameterName) {
this.parameterName = parameterName;
}
public String getContentType() {
return contentType;
}
public void setContentType(String contentType) {
this.contentType = contentType;
}
}注：以上android端上传代码是从网上借用的。对原作者表示感谢。
以上代码经本人測试，能正常进行多文件上传。