jterm

A pure-Java terminal UI toolkit for building rich TTY applications. No native dependencies. No JNI. Just Java and a terminal.

Get Started View Source

jterm — Dashboard Demo

// Build a dashboard in 15 lines of Java var gui = new DefaultTextGUI(new DefaultScreen(new AnsiTerminal())); gui.getScreen().startScreen(); var window = new WindowImpl("System Monitor"); var panel = window.getContents(); panel.setLayoutManager(new BorderLayout()); panel.addComponent(new Label("System Monitor"), new BorderLayout.BorderLayoutData(BorderLayout.Region.NORTH)); var table = new Table("Metric", "Value", "Status"); table.addRow("CPU", "12%", "OK"); table.addRow("Memory", "45%", "OK"); table.addRow("Disk", "78%", "WARN"); panel.addComponent(table, new BorderLayout.BorderLayoutData(BorderLayout.Region.CENTER)); gui.addWindow(window); gui.runEventLoop();

01Features

Everything you need to build a full terminal application — not just a menu screen.

[█]

Full Widget Set

A complete component system for building interactive TUIs.

Button, Label, TextBox, TextArea
Table, DataGrid, ListBox
CheckBox, RadioGroup, ProgressBar
MenuBar, Menu, MenuItem
Panel, Border, Separator

╭─╮

Layout Managers

Position widgets without pixel math. Let the layout engine handle it.

BorderLayout (north/south/east/west/center)
LinearLayout (horizontal/vertical)
GridLayout (rows × columns)
Nested containers for complex UIs

🎨

Themes & Styling

Full terminal color support — 16-color, 256-color, and true color RGB.

Built-in ThemeManager with swappable themes
SGR support (bold, italic, underline, blink)
Cell-level TextCell styling
CP437 box-drawing characters

▄▀▄

Charts & Data

Render data visualizations in the terminal. No external charting libs.

Line charts, bar charts, sparklines
Configurable axes, labels, colors
TableModel + DataGrid for tabular data
ResultSetGridModel — bind JDBC directly

★

Animations

25+ animated backgrounds and transition effects. Because terminals deserve to be alive.

MatrixRain, Starfield, Fireworks
MandelbrotZoom, Spirograph, PlasmaWash
Fade, Wipe, Dissolve, Slide transitions
AnimationManager with frame timing
Sprites & particle effects

⎚

ANSI Art Renderer

Render full-color ANSI art files — splash screens, logos, background art. One part of the toolkit, not the whole story.

Full SGR parser (cursor positioning, colors)
16-color, 256-color, true color support
AnsiArtRenderer for full-screen display
ScreenBuffer with double-buffering

✦

Sprites & Effects

A character-based sprite system for games, animations, and rich terminal art.

Sprite + SpriteSheet for character art
ParticleEffect for bursts and weather
AnimatedText for typewriter effects
SpriteRenderer composites onto any Screen

02Widgets

A component model that feels like Swing, not like ncurses.

Component-based architecture

jterm uses a proper component hierarchy — containers, layout managers, event listeners, focus management. Build complex multi-panel UIs the way you'd build a desktop app, not by manually positioning characters on a grid.

Component → AbstractComponent → Widget
Container → Panel → Window
FocusManager for keyboard navigation
Event listeners (click, key, focus, change)
TableModel / ListModel data binding

// A login form with proper layout
var form = new Panel(new LinearLayout(LinearLayout.Direction.VERTICAL));

var userBox = new TextBox();
var passBox = new TextBox();
passBox.setMasked(true);
var loginBtn = new Button("Sign In");

loginBtn.addListener(() -> {
    String user = userBox.getValue();
    String pass = passBox.getValue();
    authenticate(user, pass);
});

form.addComponent(new Label("Username:"));
form.addComponent(userBox);
form.addComponent(new Label("Password:"));
form.addComponent(passBox);
form.addComponent(loginBtn);
        

03Animations

Terminal applications don't have to be static. 25+ animated backgrounds and transition effects ship in the box.

▓

Animated Backgrounds

MatrixRain, Starfield, TwinkleStarfield
Fireworks, Snowfall, RainStorm
LavaLamp, Aurora, OceanWaves
CircuitBoard, PacketFlow
MandelbrotZoom, Spirograph, PlasmaWash
VoronoiCells, MoirePatterns
DNAHelix, LightningStorm
TickerTape, MarketDepth
PortfolioHeatmap, TerrainFlyover
Scanlines, PhosphorDecay

⇆

Screen Transitions

FadeTransition
WipeTransition
DissolveTransition
SlideTransition
Randomized per navigation

✦

Sprites & Effects

SpriteSheet for character art
ParticleEffect for bursts
AnimatedText for typewriter
AnimationFrame timing control

04Quick Start

Add the dependency, write a few lines, run it. That's it.

Maven

Add jterm to your pom.xml. Published to Maven Central — latest release 0.1.2.

Requires JDK 26+
No native libraries
Works on any terminal — SSH, Telnet, local console, web terminal
Single fat JAR option

<dependency>
    <groupId>io.jterm</groupId>
    <artifactId>jterm</artifactId>
    <version>0.1.2</version>
</dependency>

// Grab the latest:
// implementation("io.jterm:jterm:0.1.2")  // Gradle
        

// Hello World in jterm
import io.jterm.core.AnsiTerminal;
import io.jterm.screen.DefaultScreen;
import io.jterm.window.DefaultTextGUI;
import io.jterm.window.WindowImpl;
import io.jterm.widget.*;

public class Hello {
    public static void main(String[] args) throws Exception {
        var gui = new DefaultTextGUI(new DefaultScreen(new AnsiTerminal()));
        gui.getScreen().startScreen();

        var window = new WindowImpl("jterm");
        var panel = window.getContents();
        panel.addComponent(new Label("Hello, Terminal!"));
        var quit = new Button("Quit");
        quit.addListener(() -> System.exit(0));
        panel.addComponent(quit);

        gui.addWindow(window);
        gui.runEventLoop();
    }
}
        

05Built With jterm

jterm powers real applications — not just demos.

▣

Phosphor BBS

A full-featured SSH/Telnet BBS with message boards, real-time chat, door games, file archives, and mesh networking over LoRa radio. 870+ Java files built on jterm's widget, animation, and screen systems.

Multi-caller SSH + Telnet server
ANSI art splash screens
Animated screen transitions
Dashboard with live session monitoring
Stock/finance screens with charts

phosphorbbs.net →

07Why jterm?

The Java ecosystem deserves a terminal UI framework — not just an ANSI escape code wrapper.

☕

Pure Java

No JNI. No native binaries. No platform-specific builds. One JAR works everywhere Java does.

⚡

Modern Java

Built for JDK 26. Uses records, sealed interfaces, pattern matching, and var throughout. No legacy cruft.

🧪

Testable

2,500+ tests. Screen buffers are inspectable. Widgets render to off-screen buffers you can assert against. No terminal required to test.

🧩

Full Framework

Screen buffers, text graphics, layout managers, focus management, event listeners, component hierarchy, theming. Everything Swing has — for the terminal.

📦

Self-Contained

Zero runtime dependencies. Drop the JAR in and go. Works in standalone apps, server daemons, or embedded devices.

06Docs

API reference is generated from the source and ships with every build.

📄

Javadoc

Every public class, method, and record is documented. Generate the full API reference locally:

git clone https://github.com/phosphorbbsbot/jterm
cd jterm && mvn javadoc:javadoc
Open target/reports/apidocs/index.html

Browse the artifact on Maven Central →

🧭

Guides

Deep-dive write-ups on the architecture:

Sprite & animation guide
DataGrid design notes
8 runnable demos in src/main/java/io.jterm.demo