public boolean equals(Object o) {
        if (!(o instanceof ContactImpl)) {
            return false;
        } else {
            ContactImpl contact = (ContactImpl) o;
            if (firstName.equals(contact.firstName)
                    && lastName.equals(contact.lastName)
                    && organization.equals(contact.organization)
                    && title.equals(contact.title)) {
                return true;
            }
            return false;
        }
    }