MultiBackend.java

   1 /*
   2  * Jexer - Java Text User Interface
   3  *
   4  * The MIT License (MIT)
   5  *
   6  * Copyright (C) 2017 Kevin Lamonte
   7  *
   8  * Permission is hereby granted, free of charge, to any person obtaining a
   9  * copy of this software and associated documentation files (the "Software"),
  10  * to deal in the Software without restriction, including without limitation
  11  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
  12  * and/or sell copies of the Software, and to permit persons to whom the
  13  * Software is furnished to do so, subject to the following conditions:
  14  *
  15  * The above copyright notice and this permission notice shall be included in
  16  * all copies or substantial portions of the Software.
  17  *
  18  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  19  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  20  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
  21  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  22  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
  23  * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
  24  * DEALINGS IN THE SOFTWARE.
  25  *
  26  * @author Kevin Lamonte [kevin.lamonte@gmail.com]
  27  * @version 1
  28  */
  29 package jexer.backend;
  30
  31 import java.util.LinkedList;
  32 import java.util.List;
  33
  34 import jexer.event.TInputEvent;
  35
  36 /**
  37  * MultiBackend mirrors its I/O to several backends.
  38  */
  39 public class MultiBackend implements Backend {
  40
  41     /**
  42      * The screen to use.
  43      */
  44     private MultiScreen multiScreen;
  45
  46     /**
  47      * The list of backends to use.
  48      */
  49     private List<Backend> backends = new LinkedList<Backend>();
  50
  51     /**
  52      * Public constructor requires one backend.  Note that this backend's
  53      * screen will be replaced with a MultiScreen.
  54      *
  55      * @param backend the backend to add
  56      */
  57     public MultiBackend(final Backend backend) {
  58         backends.add(backend);
  59         if (backend instanceof TWindowBackend) {
  60             multiScreen = new MultiScreen(((TWindowBackend) backend).getOtherScreen());
  61         } else {
  62             multiScreen = new MultiScreen(backend.getScreen());
  63         }
  64     }
  65
  66     /**
  67      * Add a backend to the list.
  68      *
  69      * @param backend the backend to add
  70      */
  71     public void addBackend(final Backend backend) {
  72         backends.add(backend);
  73         if (backend instanceof TWindowBackend) {
  74             multiScreen.addScreen(((TWindowBackend) backend).getOtherScreen());
  75         } else {
  76             multiScreen.addScreen(backend.getScreen());
  77         }
  78     }
  79
  80     /**
  81      * Remove a backend from the list.
  82      *
  83      * @param backend the backend to remove
  84      */
  85     public void removeBackend(final Backend backend) {
  86         if (backends.size() > 1) {
  87             if (backend instanceof TWindowBackend) {
  88                 multiScreen.removeScreen(((TWindowBackend) backend).getOtherScreen());
  89             } else {
  90                 multiScreen.removeScreen(backend.getScreen());
  91             }
  92             backends.remove(backend);
  93         }
  94     }
  95
  96     /**
  97      * Getter for sessionInfo.
  98      *
  99      * @return the SessionInfo
 100      */
 101     public SessionInfo getSessionInfo() {
 102         return backends.get(0).getSessionInfo();
 103     }
 104
 105     /**
 106      * Getter for screen.
 107      *
 108      * @return the Screen
 109      */
 110     public Screen getScreen() {
 111         return multiScreen;
 112     }
 113
 114     /**
 115      * Subclasses must provide an implementation that syncs the logical
 116      * screen to the physical device.
 117      */
 118     public void flushScreen() {
 119         for (Backend backend: backends) {
 120             backend.flushScreen();
 121         }
 122     }
 123
 124     /**
 125      * Subclasses must provide an implementation to get keyboard, mouse, and
 126      * screen resize events.
 127      *
 128      * @param queue list to append new events to
 129      */
 130     public void getEvents(List<TInputEvent> queue) {
 131         for (Backend backend: backends) {
 132             backend.getEvents(queue);
 133         }
 134     }
 135
 136     /**
 137      * Subclasses must provide an implementation that closes sockets,
 138      * restores console, etc.
 139      */
 140     public void shutdown() {
 141         for (Backend backend: backends) {
 142             backend.shutdown();
 143         }
 144     }
 145
 146     /**
 147      * Subclasses must provide an implementation that sets the window title.
 148      *
 149      * @param title the new title
 150      */
 151     public void setTitle(final String title) {
 152         for (Backend backend: backends) {
 153             backend.setTitle(title);
 154         }
 155     }
 156
 157     /**
 158      * Set listener to a different Object.
 159      *
 160      * @param listener the new listening object that run() wakes up on new
 161      * input
 162      */
 163     public void setListener(final Object listener) {
 164         for (Backend backend: backends) {
 165             backend.setListener(listener);
 166         }
 167     }
 168
 169 }