private static void generatePatternHash(String patternStr) {
		if (null == patternStr || patternStr.isEmpty()) {
			throw new IllegalArgumentException("the arg:patternStr can not be null or empty");
		}

		hashValueOfPattern = 0;
		int sum = 0;

		for (int i = 0; i < patternStr.length(); i++) {
			char c = patternStr.charAt(i);
			sum += (int) c;
		}

		hashValueOfPattern = sum * FACTOR;
	}