Blackdown Java was a

Linux Linux ( or ) is a family of open-source Unix-like operating systems based on the Linux kernel, an operating system kernel first released on September 17, 1991, by Linus Torvalds. Linux is typically packaged as a Linux distribution, which ...

port A port is a maritime facility comprising one or more wharves or loading areas, where ships load and discharge cargo and passengers. Although usually situated on a sea coast or estuary, ports can also be found far inland, such as Ham ...

Sun Microsystems Sun Microsystems, Inc. (Sun for short) was an American technology company that sold computers, computer components, software, and information technology services and created the Java programming language, the Solaris operating system, ZFS, the ...

Java virtual machine A Java virtual machine (JVM) is a virtual machine that enables a computer to run Java programs as well as programs written in other languages that are also compiled to Java bytecode. The JVM is detailed by a specification that formally describes ...

, developed by a group of volunteers led by Juergen Kreileder, Steve Byrne, and Karl Asha, and included a team of volunteers from around the globe. The first version, 1.0.2, was released in October 1996, predating Sun's official Linux port. Blackdown Java supported Linux on

architectures Architecture is the art and technique of designing and building, as distinguished from the skills associated with construction. It is both the process and the product of sketching, conceiving, planning, designing, and constructing buildings o ...

that the official version did not, including

SPARC SPARC (Scalable Processor Architecture) is a reduced instruction set computer (RISC) instruction set architecture originally developed by Sun Microsystems. Its design was strongly influenced by the experimental Berkeley RISC system developed ...

and

PowerPC PowerPC (with the backronym Performance Optimization With Enhanced RISC – Performance Computing, sometimes abbreviated as PPC) is a reduced instruction set computer (RISC) instruction set architecture (ISA) created by the 1991 Apple Inc., App ...

. The Blackdown project ended in August 2007, after Sun released an open source version of the HotSpot JVM as part of

OpenJDK OpenJDK (Open Java Development Kit) is a free and open-source implementation of the Java Platform, Standard Edition (Java SE). It is the result of an effort Sun Microsystems began in 2006. The implementation is licensed under the GPL-2.0-only wi ...

; OpenJDK is available under the free

GNU General Public License The GNU General Public License (GNU GPL or simply GPL) is a series of widely used free software licenses that guarantee end users the Four Freedoms (Free software), four freedoms to run, study, share, and modify the software. The license was th ...

. The Java software itself still exists on many mirrors. At its close, Blackdown supported J2SE versions 1.4.2 on i386 and AMD64, 1.4.1 on SPARC, and 1.3.1 on PowerPC. Work on J2SE 1.5.x support for x86, AMD64, SPARC, and PowerPC had been announced, but was never released. In 1999 Sun Microsystems and Inprise announced a port of Java to Linux. The port was based on Blackdown work, but the Blackdown team was not recognized or given any credit for the release. After some controversy, Sun publicly apologized to the Blackdown developers. The incident revealed that there were long standing problems between Sun and Blackdown. Despite widespread confusion, Blackdown was neither

free software Free software or libre software is computer software distributed under terms that allow users to run the software for any purpose as well as to study, change, and distribute it and any adapted versions. Free software is a matter of liberty, no ...

nor

open-source software Open-source software (OSS) is computer software that is released under a license in which the copyright holder grants users the rights to use, study, change, and distribute the software and its source code to anyone and for any purpose. Op ...

; this was due to licensing restrictions from Sun Microsystems. Its binary redistribution policy allowed it to be pre-installed or included with many

Linux distributions A Linux distribution (often abbreviated as distro) is an operating system made from a software collection that includes the Linux kernel and, often, a package management system. Linux users usually obtain their operating system by downloading one ...

(e.g.,

Gentoo Linux Gentoo Linux (pronounced ) is a Linux distribution built using the Portage package management system. Unlike a binary software distribution, the source code is compiled locally according to the user's preferences and is often optimized for the ...

), whereas at the time, Sun Java's binary redistribution policy did not. Since Java 5, the Operating System Distributor License for Java (DLJ) met many Linux distributions' requirements, lessening the demand for the older Blackdown JVM. The Blackdown team pioneered Sun's involvement with external, volunteer efforts. Steve Byrne, who was working at Sun at the time, worked with Sun legal to establish an agreement to license the Java test suite for a few Blackdown participants at no cost, and this was used to certify the Blackdown Java implementation as being 100% Java compatible. The Blackdown team received recognition at the JavaOne conference in 1998 for the work that the team had been doing.

Notes

{{Java (Sun) Discontinued Java virtual machines