About Jexer

The Jexer Project strives to create an excellent cross-platform Text User Interface (TUI) appropriate for use in new projects. Jexer is intended to outwardly resemble the DOS-era Turbo Vision library from Borland, but its internal design is entirely new.

Jexer is Copyrighted (c) 2013-2022 Autumn Lamonte. Version 0.0.1 through 0.0.3 (spanning the years 2013-2016) are licensed under the Lesser GNU Public License version 3 or later. Version 0.0.4 and later are licensed under the MIT license.

Jexer is free to be used in both open-source and proprietary projects.

The Turbo Vision library was originally developed by Borland around 1990 and used in its Pascal and C++ development environments. The library was also used by a number of commercial DOS-based products in the early 1990's. Borland eventually "sort of" declared the library in the public domain. Three major derivatives were produced from Borland's code:

• Sergio Sigala's C++ version based on the "public domain" sources released by Borland: http://tvision.sourceforge.net/.
• Graphics Vision: a shareware Turbo Vision API-compatible (Pascal) library for DOS that draws super-VGA graphics loosely resembling Windows 3.x.
• Free Vision, a version of Graphics Vision ported to Free Pascal around 1999. Early versions of Free Vision (see below) appear to use code from Borland's examples. http://wiki.freepascal.org/Free_Vision.

"Public domain" is in quotes above due to the following email from Richard Stallman posted to the Debian legal mailing list in January 2000:

To: lubaldo@adinet.com.uy
Cc: debian-legal@lists.debian.org, salvador@inti.gov.ar, cbf@redlider.com.uy
Subject: Re: RHTVision and SETEdit, non-free? are they distributable at all? Anything that can be done about?
From: Richard Stallman 
Date: Fri, 14 Jan 2000 18:40:46 -0700 (MST)
Message-id: <200001150140.SAA15583@aztec.santafe.edu>
Reply-to: rms@gnu.org
In-reply-to: <387F6FD6.EB98E175@adinet.com.uy> (message from Ivan Baldo on Fri, 14 Jan 2000 15:49:58 -0300)
References: <387F6FD6.EB98E175@adinet.com.uy>

> The RHTVision library source code is based from the source code of the
> Turbo Vision library made long time ago by Borland Corporation, now
> Inprise.

Unfortunately, Turbo Vision is not free software.  The things Borland
has said about Turbo Vision are somewhat contradictory, but our lawyer
looked at them just this week and says that we cannot treat it as free
software.  In particular, he said that Turbo Vision is not "public
domain."

I asked people at Borland, a few months ago, if they would reconsider
the decision, but they said no.

As regards RHTVision, I know it is not free software.  It could be
illegal to distribute it at all.  I have not looked at that question
because, for the Free Software Movement, it is not a crucial question.
For me, the crucial point is that we need a free alternative.

As far as I am aware, every library except Jexer that produces Turbo Vision-like output was in some way derived from the original Borland codebase. Hence all of the libraries above that were connected to Borland's codebase may someday be at risk of either being deemed non-free software, or even worse being considered infringing on Embarcadero's copyright on the Turbo Vision API (depending on the final outcome of the Oracle vs Google lawsuit).

Jexer, however, is a brand new open source codebase, initially written as a LGPL-licensed D language project, now a MIT-licensed 100% Java project, with an entirely free-to-use API.

On the outside Jexer looks a lot like Turbo Vision, but some behaviors are quite different. On the inside, however, Jexer has a wildly different API: rather than Views it has TWidgets; event handlers are named onKeypress(), onMouseDown(), etc. (more like MFC and Qt); it uses separate threads to handle I/O; and many more things. Jexer's API will continue to evolve to meet new use cases.