/*
* This file is part of lanterna (http://code.google.com/p/lanterna/).
*
* lanterna is free software: you can redistribute it and/or modify
* it under the terms of the GNU Lesser General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*
* Copyright (C) 2010-2017 Martin Berglund
*/
package com.googlecode.lanterna.gui2.dialogs;
/**
* Interface to implement for custom validation of text input in a {@code TextInputDialog}
* @author Martin
*/
public interface TextInputDialogResultValidator {
/**
* Tests the content in the text box if it is valid or not
* @param content Current content of the text box
* @return {@code null} if the content is valid, or an error message explaining what's wrong with the content
* otherwise
*/
String validate(String content);
}