SquirrelJME/SquirrelJME

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# SquirrelJME

**SquirrelJME** is a Java ME 8 Virtual Machine for embedded and Internet of
Things devices. It has the ultimate goal of being 99.9% compatible with the
Java ME standard.

This project is purely written in Java, with a small secondary C project, and 
is very easy to port to different hardware. For running on native hardware, a
compiler handles the conversion of Java byte code to machine code (in an
intermediate format). Any system specific APIs are accessed via standardized
system calls that handle the logic the compiler cannot provide. An execution
engine which is written in C, it offers a lightweight method of code
execution.

Additionally, there is a port of SquirrelJME to RetroArch which enables the
ability to play older J2ME software and games designed for flip-phones.

 * Copyright (C) 2013-2024 Stephanie Gawroriski <xer@multiphasicapps.net>
 * "SquirrelJME" and "Lex" are trademarked by Stephanie Gawroriski 2016-2024
 * _Lex_ and The _SquirrelJME_ Logo were illustrated by...
   * Kat Adam-MacEwen
   * Kat@CMYKat Designs & Illustrations <http://www.cmykat-designs.com/>

Please support me on [Patreon](https://www.patreon.com/SquirrelJME)!

Dedicated to _Emily_ (1998-2020), the developer of
[Mu](https://github.com/meepingsnesroms/Mu), you will not be forgotten.
Rest in peace.

Dedicated to _Near_ (1983-2021), the developer of Higan, Ares, etc., may
your soul rest in peace. You will not be forgotten.

_I am currently searching for employment! Check out my_
_[LinkedIn](https://www.linkedin.com/in/xerthesquirrel/)!_

_SquirrelJME_ utilizes _Install4J_ for cross-platform installers, you can
read more about it and check out their product page at:

 * [Install4J Multi-Platform Installer Builder](
    https://www.ej-technologies.com/products/install4j/overview.html)

Badges:

 * _Checks and Quality_
   * [![CircleCI](
     https://img.shields.io/circleci/build/github/SquirrelJME/SquirrelJME/trunk.svg?label=CircleCI%20Build)](
     https://circleci.com/gh/SquirrelJME/SquirrelJME/tree/trunk)
   * [![Code Climate Maintainability](
     https://img.shields.io/codeclimate/maintainability-percentage/SquirrelJME/SquirrelJME)](
     https://codeclimate.com/github/SquirrelJME/SquirrelJME)
     [![Code Climate technical debt](
     https://img.shields.io/codeclimate/tech-debt/SquirrelJME/SquirrelJME)](
     https://codeclimate.com/github/SquirrelJME/SquirrelJME)
   * [![Docker Build](
     https://img.shields.io/docker/cloud/build/xerthesquirrel/squirreljme.svg?label=Docker%20Container)](
     https://hub.docker.com/r/xerthesquirrel/squirreljme/builds)
   * [![RetroArch Core](
     https://git.libretro.com/libretro/SquirrelJME/badges/trunk/pipeline.svg?key_text=RetroArch%20Core&key_width=115)](
     https://git.libretro.org/libretro/SquirrelJME)
 * _Social and Community_
   * [![Discord](https://img.shields.io/discord/278929900893634560.svg?label=Discord%20Server)](
     https://discord.gg/9PkMMKt)
   * [![Twitter](
     https://img.shields.io/twitter/follow/SquirrelJME.svg?label=Follow%20on%20Twitter)](
     https://twitter.com/SquirrelJME)
 * _Downloads and Activity_
   * ![Commit Activity](
     https://img.shields.io/github/commit-activity/w/SquirrelJME/SquirrelJME.svg?label=Code%20Commits)
   * [![Docker Pulls](
     https://img.shields.io/docker/pulls/xerthesquirrel/squirreljme?label=Docker%20Pulls)](
     https://hub.docker.com/r/xerthesquirrel/squirreljme)
   * [![SourceForge Downloads](
     https://img.shields.io/sourceforge/dm/squirreljme.svg?label=SourceForge%20Downloads)](
     https://sourceforge.net/projects/squirreljme/files/)
 * _Donations_
   * [![Liberapay](
     https://img.shields.io/liberapay/receives/xershadowtail.svg?logo=liberapay&label=LiberaPay)](
     https://liberapay.com/xershadowtail)

Information:

 * [User Guide](assets/user-guide/readme.mkd)
 * [Code of Conduct](code-of-conduct.mkd)
 * [License](license.mkd)
   * _Source_: Mozilla Public License 2.0
   * _Assets_: Creative Commons CC-BY-SA 4.0
   * _Fonts_ : SIL Open Font License Version 1.1
   * [Third Party Licenses](third-party.mkd)
 * [Contributing to SquirrelJME](contributing.mkd)
   * [Credits of Contributions](credits.mkd)
   * [Test Writing](test-writing.mkd)
 * _End-User Documents_
   * [Building](building.mkd)
   * [Changelog](changelog.mkd)
   * [Compatibility](compatibility.mkd)
   * [History](history.mkd)
   * [Release Roadmap](route.mkd)
 * _Developer Resources_
   * [CircleCI Status](
     https://circleci.com/gh/SquirrelJME/SquirrelJME/tree/trunk)
   * [Developer Guide](developer-guide.mkd)
   * [Developer Notes](assets/developer-notes/index.mkd)
   * [Design Document](design.mkd)
   * [Porting SquirrelJME](porting.mkd)
   * [Project Scope](scope.mkd)
   * [CLDC 1.8 API (docs.oracle.com)](
     https://docs.oracle.com/javame/8.0/api/cldc/api/overview-summary.html)

## Repository

 * [Online repository](http://squirreljme.cc/)
   ([HTTPS](https://squirreljme.cc/),
   [Tor (A)](http://vzwveldr7djnlpg7ujslaqre632htbl3unkmfbltpgumevw63jn47dad.onion/),
   [Tor (B)](http://hrkzpyi33og6j5z3anfpjuqkawvkw4kxyasrp64elg3i6dffihmdhxad.onion/))
 * SquirrelJME uses `fossil` <http://fossil-scm.org/>.
 * The repository may be cloned using Fossil:
   * One of these commands:
     * `fossil clone -u http://squirreljme.cc/ squirreljme.fossil`
     * `fossil clone -u https://squirreljme.cc/ squirreljme.fossil`
     * `fossil clone -u http://vzwveldr7djnlpg7ujslaqre632htbl3unkmfbltpgumevw63jn47dad.onion/ squirreljme.fossil`
     * `fossil clone -u http://hrkzpyi33og6j5z3anfpjuqkawvkw4kxyasrp64elg3i6dffihmdhxad.onion/ squirreljme.fossil`
     * `fossil clone -u http://squirrelmfbf2udn.onion/ squirreljme.fossil`
   * `mkdir squirreljme`
   * `cd squirreljme`
   * `fossil open ../squirreljme.fossil`
 * Alternatively via [GitHub](https://github.com/SquirrelJME/SquirrelJME):
   * `git clone https://github.com/SquirrelJME/SquirrelJME`
   * `cd SquirrelJME`
 * Alternatively via [repo.or.cz](https://repo.or.cz/SquirrelJME.git):
   * `git clone https://repo.or.cz/SquirrelJME.git`
   * `cd SquirrelJME`
 * Trunk Source Snapshot (Main website or `fossil serve` only):
   * [TAR.GZ](/tarball/squirreljme-trunk.tar.gz?uuid=trunk)
   * [ZIP](/zip/squirreljme-trunk.zip?uuid=trunk)

## Links

 * [My Portfolio](https://shadowtail.dev/)
 * [My Public PGP Key](public-key.gpg.mkd)
 * [SquirrelJME BlueSky](https://bsky.app/profile/squirreljme.bsky.social)
 * [SquirrelJME Twitter](https://twitter.com/SquirrelJME)
 * [SquirrelJME Mastodon](https://mastodon.online/@SquirrelJME)
 * Locations where you can get support:
   * [Discord](https://discord.gg/9PkMMKt)
   * _LiberaChat (IRC)_ (Bridged to _Discord_)
     * [#squirreljme](ircs://irc.libera.chat:6697/squirreljme) -- Main Support
     * [#squirreljme-softwares](ircs://irc.libera.chat:6697/squirreljme-software) -- Software channel
     * [##squirreljme](ircs://irc.libera.chat:6697/#squirreljme) -- Off-Topic
   * [Reddit](https://reddit.com/r/SquirrelJME)
 * Front facing social media:
   * [BlueSky](https://bsky.app/profile/squirreljme.bsky.social)
   * [Mastodon (mastodon.online)](https://mastodon.online/@SquirrelJME)
   * [YouTube](https://www.youtube.com/channel/UCbmC7qQjeXUEUyE5XfDX5RA/)
   * [Twitter](https://twitter.com/SquirrelJME)
 * [Docker Hub](https://hub.docker.com/r/xerthesquirrel/squirreljme)
 * [SourceForge](https://sourceforge.net/p/squirreljme/)
 * Personal Accounts (If you wish to contact me this way)
   * [GitHub](https://github.com/XerTheSquirrel/)
   * [Keybase](https://keybase.io/xerthesquirrel)
   * [LinkedIn](https://www.linkedin.com/in/xerthesquirrel/)
   * [Mastodon (chitter.xyz)](https://chitter.xyz/@XerShadowTail)
   * [BlueSky](https://bsky.app/profile/xershadowtail.bsky.social)
   * [Twitter](https://twitter.com/XerShadowTail)
   * [Cohost](https://cohost.org/XerShadowTail)
   * [YouTube (Personal)](
     https://www.youtube.com/channel/UCJ4QrvbDhjtd7u6EpfBQ__g)
   * E-Mail: <xer@multiphasicapps.net>

## Goals

 * _To be small_ - Smaller programs are easier to maintain and are usually
   simpler.
 * _To be fast_ - With the potential of AOT/JIT, systems that do not normally
   have a port of an existing virtual machine will usually only have an
   interpreter.
 * _To be compatible_ - So that existing Java ME 8 applications can run on this
   virtual machine, along with J2ME applications when required. This has the
   added bonus of allowing one to use older software to catalog for
   preservation.
 * _To compile once and run anywhere_ - Current and up to date Java
   implementations are limited only to a few select systems (_Solaris_,
   _Linux_, _BSD_, _Mac OS X_, and _Windows_). Java ME 8 as of this writing
   only supports the *FRDM-K64F* (dropped), *STM32429I-EVAL*, *Raspberry Pi*,
   *Intel Galileo Gen2* (preview), and *STM 32F746G DISCOVERY* (preview) all
   of which are either out of date or discontinued by their manufacturers.
   There are multitudes of devices that support **J2ME**, however that is
   horribly out of date when compared with the Java that is used today
   (**J2ME** is equal to Java 1.4 which was released in _2002_).

## Donations

You may donate to SquirrelJME to which would be used by the author to keep the
web server online, the purchasing of new hardware/software, and for the
purchasing of food items for consumption.

 * Traditional
   * [Ko-Fi](http://ko-fi.com/xerthesquirrel)
   * [Patreon](https://www.patreon.com/SquirrelJME)
   * [Liberapay](https://liberapay.com/xershadowtail)

## Important Statements

***JAVA AND ALL OTHER RELATED TRADEMARKS AND COPYRIGHTS ARE OWNED BY ORACLE
CORPORATION <http://www.oracle.com/>.***

***SQUIRRELJME IS NEITHER PRODUCED BY, ENDORSED BY, NOR SUPPORTED BY
_ORACLE CORPORATION_.***

***ALL SOURCE CODE IS WRITTEN BY MYSELF WITH FUNCTIONALITY DETERMINED BY THE
DOCUMENTED APIS AND RUN-TIME BEHAVIOR. I HAVE NOT LOOKED AT THE SOURCE CODE FOR
OTHER IMPLEMENTATIONS, NEITHER FREE SOFTWARE NOR PROPRIETARY IMPLEMENTATIONS.
ESSENTIALLY SQUIRRELJME IS A CLEAN-ROOM IMPLEMENTATION OF THE DESIGN OF JAVA
ME 8. THE IMPLEMENTATIONS OF THE JAVA ME 8 APIS AND ASSOCIATED JSRS/JEPS IS
CONSIDERED BY MYSELF (STEPHANIE GAWRORISKI) TO BE IN THE FAIR USE.***

***THIS SOFTWARE IS INCOMPLETE AND IN ITS CURRENT STATE IS NOT CURRENTLY
100% COMPATIBLE WITH JAVA ME 8. THERE ARE CURRENTLY NO STABLE RELEASED VERSIONS
OF THIS SOFTWARE. AS SUCH THE FIRST MAJOR VERSION RELEASE WILL BE WHEN IT IS
COMPATIBLE SO AS TO NOT VIOLATE POTENTIAL LICENSES, AND IF POSSIBLE BE VERIFIED
WITH ANY APPLICABLE TCKS (SO IT WOULD BE AN "OFFICIAL" IMPLEMENTATION).***