https://github.com/mabe02/lanterna: Java library for creating text-based terminal GUIs
  • Martin Berglund 
/*
 * This file is part of lanterna (https://github.com/mabe02/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) 2010-2020 Martin Berglund
 */
package com.googlecode.lanterna.graphics;

import java.io.IOException;


Describes an area that can be 'scrolled', by moving a range of lines up or down. Certain terminals will implement
this through extensions and are much faster than if lanterna tries to manually erase and re-print the text.

Author:Andreas
/**
 * Describes an area that can be 'scrolled', by moving a range of lines up or down. Certain terminals will implement
 * this through extensions and are much faster than if lanterna tries to manually erase and re-print the text.
 *
 * @author Andreas
 */
public interface Scrollable {
    
Scroll a range of lines of this Scrollable according to given distance.
If scroll-range is empty (firstLine > lastLine || distance == 0) then
this method does nothing.
Lines that are scrolled away from are cleared.
If absolute value of distance is equal or greater than number of lines
in range, then all lines within the range will be cleared.
 

Params:
  • firstLine – first line of the range to be scrolled (top line is 0)
  • lastLine – last (inclusive) line of the range to be scrolled
  • distance – if > 0: move lines up, else if < 0: move lines down.
Throws:
  • IOException – If there was an I/O error when running the operation
/**
     * Scroll a range of lines of this Scrollable according to given distance.
     * 
     * If scroll-range is empty (firstLine &gt; lastLine || distance == 0) then
     * this method does nothing.
     * 
     * Lines that are scrolled away from are cleared.
     * 
     * If absolute value of distance is equal or greater than number of lines
     * in range, then all lines within the range will be cleared.
     *  
     * @param firstLine first line of the range to be scrolled (top line is 0)
     * @param lastLine last (inclusive) line of the range to be scrolled
     * @param distance if &gt; 0: move lines up, else if &lt; 0: move lines down.
     * @throws IOException If there was an I/O error when running the operation
     */
    void scrollLines(int firstLine, int lastLine, int distance) throws IOException;
}