public static String Map2JSON(Map<?,?> map) {
		String output = "";
		output = output + "{";
		for (Map.Entry<?, ?> e : map.entrySet()) {
			if (output.length() > 1) output = output + ",";
			String key = json_escape(String.valueOf(e.getKey()));
			String value = json_escape(String.valueOf(e.getValue()));
			output = output + "\"" + key + "\"" + ":" + "\"" + value + "\"";
		}
		output = output + "}";
		return output;
		//{"balance":1000.21,"num":100,"nickname":null,"is_vip":true,"name":"foo"}
	}