unicode

public static String chinese2Unicode(String str) {
		StringBuilder sb = new StringBuilder();
		for (char c : str.toCharArray()) {
			if (isChinese(c)) {
				sb.append("\\u" + Integer.toHexString(c));
			} else {
				sb.append(c);
			}
		}
		return sb.toString();
	}

	public static boolean isChinese(char c) {
		Character.UnicodeBlock ub = Character.UnicodeBlock.of(c);
		if (ub == Character.UnicodeBlock.CJK_UNIFIED_IDEOGRAPHS
				|| ub == Character.UnicodeBlock.CJK_COMPATIBILITY_IDEOGRAPHS
				|| ub == Character.UnicodeBlock.CJK_UNIFIED_IDEOGRAPHS_EXTENSION_A
				|| ub == Character.UnicodeBlock.GENERAL_PUNCTUATION
				|| ub == Character.UnicodeBlock.CJK_SYMBOLS_AND_PUNCTUATION
				|| ub == Character.UnicodeBlock.HALFWIDTH_AND_FULLWIDTH_FORMS) {
			return true;
		}
		return false;
	}

public static String unicodeToString(String str) {
		Pattern pattern = Pattern.compile("(\\\\u(\\p{XDigit}{4}))");
		Matcher matcher = pattern.matcher(str);
		char ch;
		while (matcher.find()) {
			String result = matcher.group(2);
			ch = (char) Integer.parseInt(result, 16);
			str = str.replace(matcher.group(1), ch + "");
		}
		return str;
	}

public String escapeHtml(String s) {
		if (s == null || s.trim().length() == 0) {
			return s;
		}
		s = s.replace("&", "&");
		s = s.replace("<", "&lt;");
		s = s.replace(">", "&gt;");
		s = s.replace("\"", "&quot;");
		return s;
	}

	public String unescapeHtml(String s) {
		if (s == null || s.trim().length() == 0) {
			return s;
		}
		s = s.replace("&quot;", "\"");
		s = s.replace("&lt;", "<");
		s = s.replace("&gt;", ">");
		s = s.replace("&amp;", "&");
		return s;
	}