Example of threading in Lanterna 3.

Lanterna3 Thread Example.java

package lanternaexample;

import com.googlecode.lanterna.TextColor;
import com.googlecode.lanterna.gui2.BasicWindow;
import com.googlecode.lanterna.gui2.DefaultWindowTextGUI;
import com.googlecode.lanterna.gui2.EmptySpace;
import com.googlecode.lanterna.gui2.Label;
import com.googlecode.lanterna.gui2.StackedModalWindowManager;
import com.googlecode.lanterna.gui2.TextGUI;
import com.googlecode.lanterna.gui2.Window;
import com.googlecode.lanterna.gui2.dialogs.WaitingDialog;
import com.googlecode.lanterna.screen.Screen;
import com.googlecode.lanterna.screen.TerminalScreen;
import com.googlecode.lanterna.terminal.ansi.TelnetTerminal;
import com.googlecode.lanterna.terminal.ansi.TelnetTerminalServer;
import java.io.IOException;
import java.net.SocketTimeoutException;
import java.util.Collections;
import java.util.HashSet;
import java.util.Set;
import java.util.concurrent.ConcurrentHashMap;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
import java.util.concurrent.Future;
import java.util.logging.Level;
import java.util.logging.Logger;

public class Main {

    //Port to listen on
    public static final int LISTEN_PORT = 1099;
    //Socket connect timeout
    public static final int SO_TIMEOUT = 200;
    //The Terminal Server Thread
    private static final ExecutorService TERMINAL_SERVER_THREAD = Executors.newSingleThreadExecutor();
    //The program thread pool...  Its unbounded, be careful.
    private static final ExecutorService PROGRAM_THREADS = Executors.newCachedThreadPool();

    public static final void main(String[] args) throws IOException {
        TelnetTerminalServer server = new TelnetTerminalServer(LISTEN_PORT);
        server.setSocketTimeout(SO_TIMEOUT);
        System.out.println(String.format("Listening on port %s", LISTEN_PORT));
        TERMINAL_SERVER_THREAD.submit(new TerminalServerThread(server));
        System.out.println("Press any key to quit...");
        System.in.read();
        System.out.println("Stopping threads...");
        TERMINAL_SERVER_THREAD.shutdownNow();
        PROGRAM_THREADS.shutdownNow();
        System.out.println("Exiting...");
    }

    private static class TerminalServerThread implements Runnable {

        TelnetTerminalServer server;

        public TerminalServerThread(TelnetTerminalServer server) {
            this.server = server;
        }

        @Override
        public void run() {
            int connectionsMade = 0;
            while (!Thread.currentThread().isInterrupted()) {
                try {
                    TelnetTerminal tt = server.acceptConnection();
                    System.out.println(String.format("Accepted connection #%s from %s", ++connectionsMade, tt.getRemoteSocketAddress()));
                    PROGRAM_THREADS.submit(new TerminalProgramThread(tt));
                } catch (SocketTimeoutException ex) {
                    //We expect this to happen... So do nothing
                } catch (IOException ex) {
                    Logger.getLogger(Main.class.getName()).log(Level.SEVERE, null, ex);
                }
            }
            System.out.println("Interrupt cought, ending...");
            Thread.currentThread().interrupt();
        }
    }

    private static class TerminalProgramThread implements Runnable {

        TelnetTerminal tt;

        private static int currentColor = 0;
        private static final TextColor.ANSI[] COLORS = {
            TextColor.ANSI.BLUE,
            TextColor.ANSI.CYAN,
            TextColor.ANSI.GREEN,
            TextColor.ANSI.MAGENTA,
            TextColor.ANSI.RED,
            TextColor.ANSI.WHITE,
            TextColor.ANSI.YELLOW
        };

        public TerminalProgramThread(TelnetTerminal tt) {
            this.tt = tt;
        }

        @Override
        public void run() {
            try {
                tt.setTerminalSize(32, 24);
                Screen screen = new TerminalScreen(tt);
                DefaultWindowTextGUI gui = new DefaultWindowTextGUI(screen, new StackedModalWindowManager(), new EmptySpace(COLORS[currentColor]));
                currentColor++;
                if (currentColor >= COLORS.length) {
                    currentColor = 0;
                }
                screen.startScreen();

                Window w = new BasicWindow("Waiting");
                Label timeLabel = new Label("Welcome!");
                w.setComponent(timeLabel);
                gui.getWindowManager().addWindow(w);
                gui.updateScreen();
                for (int i = 10; i > 0; i--) {
                    timeLabel.setText(String.format("Exiting in %s seconds.", i));
                    gui.updateScreen();
                    try {
                        Thread.sleep(1000);
                    } catch (InterruptedException ex) {
                        timeLabel.setText("Server shutting down...");
                        gui.updateScreen();
                        try {
                            Thread.sleep(200);
                        } catch (InterruptedException ex1) {

                        } finally {
                            Thread.currentThread().interrupt();
                            tt.close();
                            return;
                        }
                    }
                }
                timeLabel.setText(String.format("Time is up!"));
                gui.updateScreen();
                tt.close();
            } catch (IOException ex) {
                Logger.getLogger(Main.class.getName()).log(Level.SEVERE, null, ex);
            }
        }

    }
}