public static void recursiveZipDirectory(File sourceFolder, ZipOutputStream zipStream) throws IOException {
		String[] dirList = sourceFolder.list();
		byte[] readBuffer = new byte[2156];
		int bytesIn = 0;
		for (int i = 0; i < dirList.length; i++) {
			File f = new File(sourceFolder, dirList[i]);
			if (f.isDirectory()) {
				recursiveZipDirectory(f, zipStream);
				continue;
			} else {
				FileInputStream input = new FileInputStream(f);
				ZipEntry anEntry = new ZipEntry(f.getPath());
				zipStream.putNextEntry(anEntry);
				while((bytesIn = input.read(readBuffer)) != -1)
					zipStream.write(readBuffer, 0, bytesIn);
				input.close();
			}
		}
	}