private boolean compareContentFile(File first, File second) {
		int size = 1024;
		if (first.length() < size) size = (int)first.length(); 
		byte firstArray[] = new byte[size];
		byte secondArray[] = new byte[size];

		try{
			InputStream isFirst  = new FileInputStream(first);
			InputStream isSecond = new FileInputStream(second);
			while ((isFirst.read(firstArray)) > 0 
					&& (isSecond.read(secondArray) > 0)){
				for (int i=0; i<firstArray.length; i++) {
					if (firstArray[i] != secondArray[i]) return false;
				}
			}
			if (isFirst != null) isFirst.close();
			if (isSecond != null) isSecond.close();
		} catch (Exception e) {
			e.printStackTrace();
			return false;
		}
		return true;
	}