自己对html字符串转义

http://lxs647.iteye.com/blog/800722

public static String htmlEncode(String source) {
		if (source == null) {
			return "";
		}
		String html = "";
		StringBuffer buffer = new StringBuffer();
		for (int i = 0; i < source.length(); i++) {
			char c = source.charAt(i);
			switch (c) {
			case '<':
				buffer.append("&lt;");
				break;
			case '>':
				buffer.append("&gt;");
				break;
			case '&':
				buffer.append("&amp;");
				break;
			case '"':
				buffer.append("&quot;");
				break;
			case ' ':
				buffer.append("&nbsp;");
				break;
			case 9:
				buffer.append("&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;");
				break;
			case 10:
			case 13:
				break;
			default:
				buffer.append(c);
			}
		}
		html = buffer.toString();
		return html;
	}