public String wrapper(String content) {
		if (content == null) return "";
		
		String spanStart = "<span style=\"background-color: yellow;\">";
		String spanEnd = "</span>";
		String result = content;
		String keyWord = this.keyWord.toLowerCase();
		int position = 0;
		while(true) {
			if (position >= result.length()) break;
			
			int index = result.toLowerCase().indexOf(keyWord, position);			
			if (index < 0) break;
			int i = index - 1;
			if (i > -1 && Utility.delimiters.indexOf(result.charAt(i)) < 0) {
				position = index + keyWord.length();
				continue;
			}
			i = index + keyWord.length();
			if (i < result.length() - 1 && Utility.delimiters.indexOf(result.charAt(i)) < 0 ) {
				position = index + keyWord.length();
				continue;
			}
			result = result.substring(0, index) + spanStart 
					+ result.substring(index, index + keyWord.length()) + spanEnd
					+ result.substring(index + keyWord.length());
			position = index + keyWord.length() + spanStart.length();
		}
		
		return result;
	}