src/jexer/backend/ECMA48Backend.java

   1 /*
   2  * Jexer - Java Text User Interface
   3  *
   4  * License: LGPLv3 or later
   5  *
   6  * This module is licensed under the GNU Lesser General Public License
   7  * Version 3.  Please see the file "COPYING" in this directory for more
   8  * information about the GNU Lesser General Public License Version 3.
   9  *
  10  *     Copyright (C) 2015  Kevin Lamonte
  11  *
  12  * This program is free software; you can redistribute it and/or
  13  * modify it under the terms of the GNU Lesser General Public License
  14  * as published by the Free Software Foundation; either version 3 of
  15  * the License, or (at your option) any later version.
  16  *
  17  * This program is distributed in the hope that it will be useful, but
  18  * WITHOUT ANY WARRANTY; without even the implied warranty of
  19  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  20  * General Public License for more details.
  21  *
  22  * You should have received a copy of the GNU Lesser General Public
  23  * License along with this program; if not, see
  24  * http://www.gnu.org/licenses/, or write to the Free Software
  25  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
  26  * 02110-1301 USA
  27  *
  28  * @author Kevin Lamonte [kevin.lamonte@gmail.com]
  29  * @version 1
  30  */
  31 package jexer.backend;
  32
  33 import java.io.InputStream;
  34 import java.io.OutputStream;
  35 import java.io.UnsupportedEncodingException;
  36 import java.util.List;
  37
  38 import jexer.event.TInputEvent;
  39 import jexer.io.ECMA48Screen;
  40 import jexer.io.ECMA48Terminal;
  41
  42 /**
  43  * This class uses an xterm/ANSI X3.64/ECMA-48 type terminal to provide a
  44  * screen, keyboard, and mouse to TApplication.
  45  */
  46 public final class ECMA48Backend extends Backend {
  47
  48     /**
  49      * Input events are processed by this Terminal.
  50      */
  51     private ECMA48Terminal terminal;
  52
  53     /**
  54      * Public constructor.
  55      *
  56      * @param listener the object this backend needs to wake up when new
  57      * input comes in
  58      * @param input an InputStream connected to the remote user, or null for
  59      * System.in.  If System.in is used, then on non-Windows systems it will
  60      * be put in raw mode; shutdown() will (blindly!) put System.in in cooked
  61      * mode.  input is always converted to a Reader with UTF-8 encoding.
  62      * @param output an OutputStream connected to the remote user, or null
  63      * for System.out.  output is always converted to a Writer with UTF-8
  64      * encoding.
  65      * @throws UnsupportedEncodingException if an exception is thrown when
  66      * creating the InputStreamReader
  67      */
  68     public ECMA48Backend(final Object listener, final InputStream input,
  69         final OutputStream output) throws UnsupportedEncodingException {
  70
  71         // Create a terminal and explicitly set stdin into raw mode
  72         terminal = new ECMA48Terminal(listener, input, output);
  73
  74         // Keep the terminal's sessionInfo so that TApplication can see it
  75         sessionInfo = terminal.getSessionInfo();
  76
  77         // Create a screen
  78         screen = new ECMA48Screen(terminal);
  79
  80         // Clear the screen
  81         terminal.getOutput().write(terminal.clearAll());
  82         terminal.flush();
  83     }
  84
  85     /**
  86      * Sync the logical screen to the physical device.
  87      */
  88     @Override
  89     public void flushScreen() {
  90         screen.flushPhysical();
  91     }
  92
  93     /**
  94      * Get keyboard, mouse, and screen resize events.
  95      *
  96      * @param queue list to append new events to
  97      */
  98     @Override
  99     public void getEvents(final List<TInputEvent> queue) {
 100         if (terminal.hasEvents()) {
 101             terminal.getEvents(queue);
 102         }
 103     }
 104
 105     /**
 106      * Close the I/O, restore the console, etc.
 107      */
 108     @Override
 109     public void shutdown() {
 110         terminal.shutdown();
 111     }
 112
 113 }