class UserIs extends GenericRecipientMatcher {

    @Override
    public void init() throws MessagingException {
        if (Strings.isNullOrEmpty(getCondition())) {
            throw new MessagingException("UserIs should have a condition composed of a list of local parts of mail addresses");
        }
        users = ImmutableSet.copyOf(Splitter.on(", ").split(getCondition()));
        if (users.isEmpty()) {
            throw new MessagingException("UserIs should have at least a user specified");
        }
    }

}