public void sendEmailToDoctor() {
        String docUserName = (String) emailDoctor_doctorComboBox.getSelectedItem();
        String subjectOfMessage = emailDoctor_enterSubject.getText();
        String bodyOfMessage = emailDoctor_message.getText();
        // in the form of user:subject:message
        String emailMessage = userNameOfCurrentUser + ":" +  subjectOfMessage + ":" + bodyOfMessage;
        Doctor docUserPicked = (Doctor) hospital.getAllStaff().get(docUserName);
        docUserPicked.getEmailMessages().add(emailMessage);

        // TODO: WRITE A EMAIL SUCCESS DIALOG
        System.out.println("You have emailed Doctor " + docUserPicked.getLastName() + ".");
    }