src/com/googlecode/lanterna/input/InputProvider.java

   1 /*
   2  * This file is part of lanterna (http://code.google.com/p/lanterna/).
   3  *
   4  * lanterna is free software: you can redistribute it and/or modify
   5  * it under the terms of the GNU Lesser General Public License as published by
   6  * the Free Software Foundation, either version 3 of the License, or
   7  * (at your option) any later version.
   8  *
   9  * This program is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU Lesser General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU Lesser General Public License
  15  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  16  *
  17  * Copyright (C) 2010-2015 Martin
  18  */
  19 package com.googlecode.lanterna.input;
  20
  21 import java.io.IOException;
  22
  23 /**
  24  * Objects implementing this interface can read character streams and transform them into {@code Key} objects which can
  25  * be read in a FIFO manner.
  26  *
  27  * @author Martin
  28  */
  29 public interface InputProvider {
  30     /**
  31      * Returns the next {@code Key} off the input queue or null if there is no more input events available. Note, this
  32      * method call is <b>not</b> blocking, it returns null immediately if there is nothing on the input stream.
  33      * @return Key object which represents a keystroke coming in through the input stream
  34      * @throws java.io.IOException Propagated error if the underlying stream gave errors
  35      */
  36     KeyStroke pollInput() throws IOException;
  37
  38     /**
  39      * Returns the next {@code Key} off the input queue or blocks until one is available. <b>NOTE:</b> In previous
  40      * versions of Lanterna, this method was <b>not</b> blocking. From lanterna 3, it is blocking and you can call
  41      * {@code pollInput()} for the non-blocking version.
  42      * @return Key object which represents a keystroke coming in through the input stream
  43      * @throws java.io.IOException Propagated error if the underlying stream gave errors
  44      */
  45     KeyStroke readInput() throws IOException;
  46 }