private void write(String chunk_uuid, String chunk) throws IOException {
		// TODO Auto-generated method stub
		FileOutputStream fos = null;
		try {
			fos = new FileOutputStream(path+chunk_uuid);
		} catch (FileNotFoundException e) {
			// TODO Auto-generated catch block
			System.out.println("The file in HDFS is broken.");
		}
		fos.write(chunk.getBytes());
		fos.close();
	}