Java Text User Interface - Fork
Go to file
Lilith 3566949d51 Update
Update wiki links
2023-11-10 15:51:42 +00:00
docs Update 2022-01-14 20:37:01 +00:00
examples Cute XTermVideoPlayer 2022-01-25 20:04:08 -06:00
misc/icons transify icon 2021-03-05 07:15:25 -06:00
resources Update to 2022 2022-01-07 06:45:15 -06:00
screenshots update pixel ops 2022-02-02 17:53:27 -06:00
src/jexer #113 allow jexer.ECMA48.iTerm2Images to work when XTVERSION is not supported 2022-02-25 13:12:39 -06:00
.classpath Test commit from within Eclipse 2015-03-21 22:54:29 -04:00
.gitignore update ignore 2022-01-28 18:31:21 -06:00
LICENSE Update to 2022 2022-01-07 10:59:06 -06:00 Update 2023-11-10 15:51:42 +00:00
build.xml dev version bump 2022-02-03 17:22:32 -06:00
pom.xml change gitlab username 2022-02-12 06:47:39 -06:00

Jexer - Java Text User Interface library

This library implements a text-based windowing system loosely reminiscent of Borland's Turbo Vision system. It looks like this:

WezTerm, translucent images

...or this:

Terminal, Image, Table

...or anything in between. Translucent windows -- including layered images -- are supported and generally look as one would expect in a modern graphical environment...but it's mostly text. Translucent windows were inspired in part by notcurses.

Jexer works on both Xterm-like terminals and Swing, and supports images in both Xterm and Swing. On Swing, images are true color; on Xterm, images are rendered as sixel, iTerm2, or Jexer images.

Support for pixel-based operations was introduced in version 1.5.0. If the terminal supports mouse mode 1016 (SGR-Pixel), one can now get smooth(er) mouse motion with custom bitmap overlaid mouse. Below is stock xterm, with a custom mouse icon, and SGR-Pixel mode active:

Xterm SGR-Pixel Mouse

A new sixel encoder was introduced in version 1.6.0, and looks and performs much better. This encoder was inspired in part by chafa's high-performance principal component analysis based sixel encoder.

PCA color matching with 128-color palette and translucent windows

Jexer can be run inside its own terminal window, with support for all of its features including images and mouse, and more terminals:

Yo Dawg...

How...? What...?

Wondering how I did it? Here you go.


Jexer is available to all under the MIT License. See the file LICENSE for the full license text.

Obtaining Jexer

Jexer is available on Maven Central:


Binary releases are available on SourceForge:

The Jexer source code is hosted at:

Why I Do Not Post My Projects Anymore

Why I Do Not Post My Projects Anymore


Programming Examples

See Xterm Window Manager for a more comprehensive demonstration of what Jexer can accomplish. Here one can see a floating terminal window over tiled terminals, two of which are showing images:

Floating terminal over tiled terminals

Jexer's examples/ folder currently contains:

jexer.demos contains official demos showing all of the existing UI controls. The demos can be run as follows:

  • 'java -jar jexer.jar' . This will use with Xterm-like sequences on non-Windows non-Mac platforms. On Windows and Mac it will use a Swing JFrame.

  • 'java -Djexer.Swing=true -jar jexer.jar' . This will always use Swing on any platform.

  • 'java -cp jexer.jar jexer.demos.Demo2 PORT' (where PORT is a number to run the TCP daemon on). This will use the Xterm backend on a telnet server that will update with screen size changes.

  • 'java -cp jexer.jar jexer.demos.Demo3' . This will use with Xterm-like sequences. One can see in the code how to pass a different InputReader and OutputReader to TApplication, permitting a different encoding than UTF-8; in this case, code page 437.

  • 'java -cp jexer.jar jexer.demos.Demo4' . This demonstrates hidden windows and a custom TDesktop.

  • 'java -cp jexer.jar jexer.demos.Demo5' . This demonstrates two demo applications using different fonts in the same Swing frame.

  • 'java -cp jexer.jar jexer.demos.Demo6' . This demonstrates two applications performing I/O across three screens: an Xterm screen and Swing screen, monitored from a third Swing screen.

  • 'java -cp jexer.jar jexer.demos.Demo7' . This demonstrates the BoxLayoutManager, achieving a similar result as the javax.swing.BoxLayout apidocs example.

  • 'java -cp jexer.jar jexer.demos.Demo8 PORT' (where PORT is a number to run the TCP daemon on). This will use the Xterm backend on a telnet server to share one screen to many terminals.

Terminal Support

Most popular terminals can run Jexer, but only a few support all of Jexer's features. Jexer is actively developed against xterm and wezterm . The table below lists the terminals last tested against Jexer:

Terminal Environment Mouse Click Mouse Cursor Images
xterm X11 yes yes yes
jexer CLI, X11, Windows yes yes yes
wezterm X11, Windows yes yes yes(7)
foot(3) Wayland yes yes yes
contour(3) X11 yes yes yes
mintty Windows yes yes yes
mlterm X11 yes yes yes
RLogin Windows yes yes yes
xterm.js(8) Web yes yes yes
alacritty(3b) X11 yes yes yes
gnome-terminal X11 yes yes no
iTerm2 Mac yes yes no(5)
kitty(3) X11 yes yes no(9)
lcxterm CLI, Linux console yes yes no
rxvt-unicode X11 yes yes no(2)
xfce4-terminal X11 yes yes no
Windows Terminal(6) Windows yes yes no
DomTerm(3) Web yes no yes
darktile X11 yes no no(5)
konsole X11 yes no no
yakuake X11 yes no no
screen CLI yes(1) yes(1) no(2)
tmux CLI yes(1) yes(1) no
putty X11, Windows yes no no(2)
qodem(3) CLI, Linux console yes yes(4) no
qodem-x11(3) X11 yes no no
yaft Linux console (FB) no no yes
Linux Linux console no no no(2)
MacTerm Mac no no no(2)

1 - Requires mouse support from host terminal.

2 - Also fails to filter out sixel data, leaving garbage on screen.

3 - Latest in repository.

3b - Latest in repository, using graphics PR branch.

4 - Requires TERM=xterm-1003 before starting.

5 - Sixel images can crash terminal.

6 - Version 1.4.3243.0, on Windows 10.0.19041.1. Tested against WSL-1 Debian instance.

7 - Both sixel and iTerm2 images.

8 - Using jerch's xterm-addon-image.

9 - Kitty image protocol support will never be in Jexer, as a matter of principle. Should that terminal adopt iTerm2 or sixel, then images could work. (Image support for kitty was removed on February 10, 2022.)

See Also

  • Xterm Window Manager is a text-based window manager. It has virtual desktops, tiled terminals with draggable resizing, cascading terminal windows, and a plugin system for adding functionality. Add LCXterm and one can have a mouse-supporting X11-like text-based "GUI" on the raw Linux console.

  • XtermDOOM is an effort to make MochaDoom run smoothly under Xterm. The game is not yet playable, but it can show off Jexer's multiplexing and multihead image capabilities. For ramblings about the game, terminal resources, etc. see /r/xtermdoom.

  • LCXterm - ouroboros fork is a curses-based terminal emulator that allows one to use Jexer with full support on the raw Linux console.

  • ptypipe is a small C utility that permits a Jexer TTerminalWindow to resize the running shell when its window is resized.

  • Tranquil Java IDE is a TUI-based integrated development environment for the Java language that was built using a very lightly modified GPL version of Jexer.


Jexer makes use of the Terminus TrueType font made available here .

Jexer incorporates some ideas done first, or better implemented, elsewhere. If you like what you see here, please take a look at these projects too: