public void sendEmail() {
        //TODO implement email sending
        if (emailSender != null) {
            if (emailSender.sendEmail(this)) {
                this.emailSentDate = new GregorianCalendar();
                this.isFinalized = true;
            } else {
                throw new UnsupportedOperationException(ExecutionDefaults.EMAIL_WAS_NOT_SENT);
            }
        } else {
            throw new UnsupportedOperationException(ExecutionDefaults.EMAIL_SENDER_IS_NOT_SET);
        }
    }