jodd-mail/src/main/java/jodd/mail/EmailUtil.java
public static boolean isEmptyFlags(Flags flags) {
		if (flags == null) return true;
		Flags.Flag[] systemFlags = flags.getSystemFlags();
		if (systemFlags != null && systemFlags.length > 0) {
			return false;
		}
		String[] userFlags = flags.getUserFlags();
		if (userFlags != null && userFlags.length > 0) {
			return false;
		}

		return true;
	}
public static boolean isEmptyFlags(Flags flags) {
		if (flags == null) return true;
		Flags.Flag[] systemFlags = flags.getSystemFlags();
		if (systemFlags != null && systemFlags.length > 0) {
			return false;
		}
		String[] userFlags = flags.getUserFlags();
		if (userFlags != null && userFlags.length > 0) {
			return false;
		}

		return true;
	}
Check whether flags is a empty flags
@param flags a flags of message to check
@return whether the flags is empty