Fullscreen Terminal Windows In Java Using Lanterna

[!warning] Hey, it’s you from 2025 Don’t do this. Don’t hurt yourself. You want to write a TUI? Don’t use Java. Use Python or Rust. That summer when you thought it was a fun idea is over.

tldr: Here’s a code snippet of a fullscreen terminal window using Lanterna.

Lanterna is an easy way to make text only user interfaces in Java that I highly recommend. One thing that took me too long to find was how to make a window fullscreen. Add:


yourWindow.setHints(java.util.Collections.singleton(Window.Hint.FULL_SCREEN));

Here’s it in a minimal example:

import java.io.IOException;
import com.googlecode.lanterna.gui2.*;
import com.googlecode.lanterna.screen.*;
import com.googlecode.lanterna.terminal.*;

public class TUI {
  public static void main(String[] args) {
    MultiWindowTextGUI gui;
    Screen screen;
    BasicWindow window;

    try (Terminal terminal = new DefaultTerminalFactory().createTerminal()) {
      screen = new TerminalScreen(terminal);
      screen.startScreen();

      gui = new MultiWindowTextGUI(screen);
      window = new BasicWindow();
      window.setComponent(new Label("Hello, fullscreen!"));
      // Set window to use fullscreen hint
      window.setHints(java.util.Collections.singleton(Window.Hint.FULL_SCREEN));
      gui.addWindowAndWait(window);
    } catch (IOException ex) {
    }
  }
}

Note: There are other hints you can use in Window.Hint you can use. Put them in a collection and pass them to the setHints method. I like Window.Hint.NO_DECORATIONS.

Note: Note: As told in the documentation, “Please note that it’s up to the window manager if these hints will be honored or not.”

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Tags: Code_Snippet, Commandline, Programming_Language/Java, Terminal, TUI