/*
* 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 .
*
* Copyright (C) 2010-2015 Martin
*/
package com.googlecode.lanterna.terminal.ansi;
import java.io.IOException;
import java.net.ServerSocket;
import java.net.Socket;
import java.nio.charset.Charset;
import javax.net.ServerSocketFactory;
/**
* This class implements a Telnet server, capable of accepting multiple clients and presenting each one as their own
* Terminal. You need to tell it at least what port to listen on and then it create a Server socket listening for
* incoming connections. Use {@code acceptConnection()} to wait for the next incoming connection, it will be returned as
* a {@code TelnetTerminal} object that represents the client and which will be the way for the server to send content
* to this client. Next connecting client (through {@code acceptConnection()} will get a different
* {@code TelnetTerminal}, i.e. their content will not be in sync automatically but considered as two different
* terminals.
* @author martin
* @see TelnetTerminal
* @see Wikipedia
*/
@SuppressWarnings("WeakerAccess")
public class TelnetTerminalServer {
private final Charset charset;
private final ServerSocket serverSocket;
/**
* Creates a new TelnetTerminalServer on a specific port
* @param port Port to listen for incoming telnet connections
* @throws IOException If there was an underlying I/O exception
*/
public TelnetTerminalServer(int port) throws IOException {
this(ServerSocketFactory.getDefault(), port);
}
/**
* Creates a new TelnetTerminalServer on a specific port, using a certain character set
* @param port Port to listen for incoming telnet connections
* @param charset Character set to use
* @throws IOException If there was an underlying I/O exception
*/
public TelnetTerminalServer(int port, Charset charset) throws IOException {
this(ServerSocketFactory.getDefault(), port, charset);
}
/**
* Creates a new TelnetTerminalServer on a specific port through a ServerSocketFactory
* @param port Port to listen for incoming telnet connections
* @param serverSocketFactory ServerSocketFactory to use when creating the ServerSocket
* @throws IOException If there was an underlying I/O exception
*/
public TelnetTerminalServer(ServerSocketFactory serverSocketFactory, int port) throws IOException {
this(serverSocketFactory, port, Charset.defaultCharset());
}
/**
* Creates a new TelnetTerminalServer on a specific port through a ServerSocketFactory with a certain Charset
* @param serverSocketFactory ServerSocketFactory to use when creating the ServerSocket
* @param port Port to listen for incoming telnet connections
* @param charset Character set to use
* @throws IOException If there was an underlying I/O exception
*/
public TelnetTerminalServer(ServerSocketFactory serverSocketFactory, int port, Charset charset) throws IOException {
this.serverSocket = serverSocketFactory.createServerSocket(port);
this.charset = charset;
}
/**
* Returns the actual server socket used by this object. Can be used to tweak settings but be careful!
* @return Underlying ServerSocket
*/
public ServerSocket getServerSocket() {
return serverSocket;
}
/**
* Waits for the next client to connect in to our server and returns a Terminal implementation, TelnetTerminal, that
* represents the remote terminal this client is running. The terminal can be used just like any other Terminal, but
* keep in mind that all operations are sent over the network.
* @return TelnetTerminal for the remote client's terminal
* @throws IOException If there was an underlying I/O exception
*/
public TelnetTerminal acceptConnection() throws IOException {
Socket clientSocket = serverSocket.accept();
clientSocket.setTcpNoDelay(true);
return new TelnetTerminal(clientSocket, charset);
}
/**
* Closes the server socket, accepting no new connection. Any call to acceptConnection() after this will fail.
* @throws IOException If there was an underlying I/O exception
*/
public void close() throws IOException {
serverSocket.close();
}
}