Android客户端向服务器传递图片(使用Http协议)

//客户端代码
public class HttpPost {
	/**
	 * 通过拼接的方式构造请求内容，实现参数传输以及文件传输
	 * 
	 * @param acti
	 *            .nUrl
	 * @param params
	 * @param files
	 * @return
	 * @throws IOException
	 */
	public static String post(String actionUrl, Map<String, String> params, Map<String, File> files) throws IOException {

		String BOUNDARY = java.util.UUID.randomUUID().toString();
		String PREFIX = "--", LINEND = "\r\n";
		String MULTIPART_FROM_DATA = "multipart/form-data";
		String CHARSET = "UTF-8";

		URL uri = new URL(actionUrl);
		HttpURLConnection conn = (HttpURLConnection) uri.openConnection();
		conn.setReadTimeout(5 * 1000); // 缓存的最长时间
		conn.setDoInput(true);// 允许输入
		conn.setDoOutput(true);// 允许输出
		conn.setUseCaches(false); // 不允许使用缓存
		conn.setRequestMethod("POST");
		conn.setRequestProperty("connection", "keep-alive");
		conn.setRequestProperty("Charsert", "UTF-8");
		conn.setRequestProperty("Content-Type", MULTIPART_FROM_DATA + ";boundary=" + BOUNDARY);

		// 首先组拼文本类型的参数
		StringBuilder sb = new StringBuilder();
		for (Map.Entry<String, String> entry : params.entrySet()) {
			sb.append(PREFIX);
			sb.append(BOUNDARY);
			sb.append(LINEND);
			sb.append("Content-Disposition: form-data; name=\"" + entry.getKey() + "\"" + LINEND);
			sb.append("Content-Type: text/plain; charset=" + CHARSET + LINEND);
			sb.append("Content-Transfer-Encoding: 8bit" + LINEND);
			sb.append(LINEND);
			sb.append(entry.getValue());
			sb.append(LINEND);
		}

		DataOutputStream outStream = new DataOutputStream(conn.getOutputStream());
		outStream.write(sb.toString().getBytes());
		// 发送文件数据
		if (files != null)
			for (Map.Entry<String, File> file : files.entrySet()) {
				StringBuilder sb1 = new StringBuilder();
				sb1.append(PREFIX);
				sb1.append(BOUNDARY);
				sb1.append(LINEND);
				sb1.append("Content-Disposition: form-data; name=\"file\"; filename=\"" + file.getKey() + "\"" + LINEND);
				sb1.append("Content-Type: application/octet-stream; charset=" + CHARSET + LINEND);
				sb1.append(LINEND);
				outStream.write(sb1.toString().getBytes());

				InputStream is = new FileInputStream(file.getValue());
				byte[] buffer = new byte[1024];
				int len = 0;
				while ((len = is.read(buffer)) != -1) {
					outStream.write(buffer, 0, len);
				}

				is.close();
				outStream.write(LINEND.getBytes());
			}

		// 请求结束标志
		byte[] end_data = (PREFIX + BOUNDARY + PREFIX + LINEND).getBytes();
		outStream.write(end_data);
		outStream.flush();
		// 得到响应码
		int res = conn.getResponseCode();
		InputStream in = conn.getInputStream();
		if (res == 200) {
			int ch;
			StringBuilder sb2 = new StringBuilder();
			while ((ch = in.read()) != -1) {
				sb2.append((char) ch);
			}
		}
		outStream.close();
		conn.disconnect();
		return in.toString();

	}

}

public class UploadServlet extends HttpServlet {
	private static final long serialVersionUID = 1L;

	/**
	 * Default constructor.
	 */
	public UploadServlet() {
		// TODO Auto-generated constructor stub
	}

	/**
	 * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse
	 *      response)
	 */
	protected void doGet(HttpServletRequest request,
			HttpServletResponse response) throws ServletException, IOException {
		// TODO Auto-generated method stub
	}

	/**
	 * @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse
	 *      response)
	 */
	public void doPost(HttpServletRequest request, HttpServletResponse response)
			throws ServletException, IOException {

		RequestContext req = new ServletRequestContext(request);
		if (FileUpload.isMultipartContent(req)) {
			DiskFileItemFactory factory = new DiskFileItemFactory();
			ServletFileUpload fileUpload = new ServletFileUpload(factory);
			fileUpload.setFileSizeMax(1024 * 1024 * 1024);

			List items = new ArrayList();
			try {
				items = fileUpload.parseRequest(request);
			} catch (Exception e) {

			}

			Iterator it = items.iterator();
			while (it.hasNext()) {
				FileItem fileItem = (FileItem) it.next();
				if (fileItem.isFormField()) {
					System.out.println(fileItem.getFieldName()
							+ " "
							+ fileItem.getName()
							+ " "
							+ new String(fileItem.getString().getBytes(
									"ISO-8859-1"), "GBK"));
				} else {
					System.out.println(fileItem.getFieldName() + " "
							+ fileItem.getName() + " " + fileItem.isInMemory()
							+ " " + fileItem.getContentType() + " "
							+ fileItem.getSize());
					if (fileItem.getName() != null && fileItem.getSize() != 0) {
						File fullFile = new File(fileItem.getName());
						File newFile = new File("F:\\upload\\"
								+ fullFile.getName());
						try {
							fileItem.write(newFile);
						} catch (Exception E) {

						}
					} else {
						System.out.println("no file choosen or empty file");
					}
				}
			}
		}
	}

}