free Java implementations

The first free project to offer substantial parts of Java platform functionality was likely guavac, which began some time before November 1995.{{cite web

|url=http://www.ccs.neu.edu/research/demeter/course/f96/hw/1/guavac-info

|title=Announcing: guavac 0.2.5, A free compiler for the Java language

|date=1996-09-07

|access-date=2007-06-24

|archive-url=https://web.archive.org/web/20090814181704/http://www.ccs.neu.edu/research/demeter/course/f96/hw/1/guavac-info

|archive-date=2009-08-14

|url-status=dead

}}{{cite web

|url=http://fresh.t-systems-sfr.com/unix/src/www/guavac-1.2.tar.gz:a/guavac-1.2/compiler/ChangeLog

|title=Changelog of guavac, showing the first release happening in January 1996

|quote=Wed Nov 22 05:43:07 1995 [...] CompilerMain.C, Compiler. C, Compiler.h, lexer.l, parser.y: Initial revision

|access-date=2007-06-24

|archive-url=https://web.archive.org/web/20070928155521/http://fresh.t-systems-sfr.com/unix/src/www/guavac-1.2.tar.gz:a/guavac-1.2/compiler/ChangeLog

|archive-date=2007-09-28

|url-status=dead

}}

Since then, the free software movement developed other Java compilers, most notably the GNU Compiler for Java. Others include the Eclipse Java Compiler (ECJ), which is maintained by the Eclipse Foundation, and Jikes, which is no longer actively maintained. Since the GNU Compiler Collection's 4.3 release, GCJ (its Java compiler) is using the ECJ parser front-end for parsing Java.{{cite web

|url=https://gcc.gnu.org/gcc-4.3/changes.html

|title=GCC 4.3 Release Series -- Changes, New Features, and Fixes

|access-date=2007-10-08

}}

Examples of free runtime environments include Kaffe, SableVM and gcj.

GNU Classpath is the main free software class library for Java. Most free runtimes use GNU Classpath as their class library.

In May 2005, Apache Harmony was announced, however, the project chose the Apache License, which was at the time incompatible with all existing free Java implementations.

Another event in May 2005 was the announcement that OpenOffice.org 2.0 would depend on Java features which free software implementations couldn't provide. Following controversy, OpenOffice.org adopted a guideline requiring it to work with free Java implementations.

Notable applications that already worked with free software Java implementations before November 2006 include OpenOffice.org and Vuze, both of which work when compiled with GCJ.

On November 13, 2006, Sun released its compiler, javac, under the GNU General Public License.[http://news.cnet.com/Sun-picks-GPL-license-for-Java-code/2100-7344_3-6134584.html Sun picks GPL license for Java code]

As of September 2007, as well as javac, Sun has released the code of HotSpot (the virtual machine) and almost all the Java Class Library as free software.

Following their promise to release a fully buildable JDK based almost completely on free and open source code in the first half of 2007,[http://www.sun.com/software/opensource/java/faq.jsp#b4 OpenJDK FAQ] {{webarchive |url=https://web.archive.org/web/20070402155851/http://www.sun.com/software/opensource/java/faq.jsp#b4 |date=April 2, 2007 }} Sun released the complete source code of the Class library under the GPL on May 8, 2007, except some limited parts that were licensed by Sun from 3rd parties who did not want their code to be released under a free software licence.{{cite web

| url=http://mail.openjdk.java.net/pipermail/announce/2007-May.txt

| title=Open JDK is here!

| publisher=Sun Microsystems

| date=2007-05-08

| access-date=2007-05-09}} Sun has stated that it aims to replace the parts that remain proprietary and closed source with alternative implementations and make the class library completely free and open source. Since there's some encumbered code in the JDK, Sun will continue to use that code in commercial releases until it's replaced by fully functional free and open-source alternatives.

{{See also|OpenJDK}}

{{Update|section|date=January 2014}}

As of May 2008, the only part of the Class library that remains proprietary (4% as of May 2007 for OpenJDK 7,

{{cite web

|url = http://weblogs.java.net/blog/robogeek/archive/2007/10/openjdk_encumbr.html

|title = Plans for OpenJDK

|last = Herron

|first = David

|date = 2007-10-04

|access-date = 2007-10-09

|url-status = dead

|archive-url = https://web.archive.org/web/20071011014156/http://weblogs.java.net/blog/robogeek/archive/2007/10/openjdk_encumbr.html

|archive-date = 2007-10-11

}}

{{cite web

| url=http://fitzsim.org/blog/?p=17

| title=Plans for OpenJDK

| last=Fitzsimmons|first=Thomas

| date=2007-05-18

| access-date=2007-05-22}}

and less than 1% as of May 2008 in OpenJDK 6

{{cite web

|url = http://langel.wordpress.com/2008/03/13/openjdk-in-fedora-9/

|title = OpenJDK to replace IcedTea in Fedora 9

|last = Angel

|first = Lillian

|date = 2008-03-13

|access-date = 2008-04-05

|url-status = dead

|archive-url = https://web.archive.org/web/20080418133611/http://langel.wordpress.com/2008/03/13/openjdk-in-fedora-9/

|archive-date = 2008-04-18

}}

{{cite web

| url=http://developer.redhatmagazine.com/2008/03/12/openjdk-to-replace-icedtea-in-fedora-9/

| title=OpenJDK in Fedora 9!

| last=Wade

| first=Karsten

| publisher=redhatmagazine.com

| quote=Thomas Fitzsimmons updated the Fedora 9 release notes source pages to reflect that Fedora 9 would ship with OpenJDK 6 instead of the IcedTea implementation of OpenJDK 7. Fedora 9 (Sulphur) is due to release in May 2008.

| date=2008-03-13

| access-date=2008-04-05

| archive-url=https://web.archive.org/web/20080421100346/http://developer.redhatmagazine.com/2008/03/12/openjdk-to-replace-icedtea-in-fedora-9/

| archive-date=2008-04-21

| url-status=dead

}})

is the SNMP implementation.{{cite web

|url=http://mail.openjdk.java.net/pipermail/jdk6-dev/2008-May/000058.html

|title=OpenJDK 6 b10 source posted

|date=2008-05-30

|access-date=2008-06-01

}}

Since the first May 2007 release, Sun Microsystems, with the help of the community, has released as free software (or replaced with free-software alternatives) almost all the encumbered code:

• All the audio engine code, including the software synthesizer, has been released as open-source.[http://openjdk.java.net/projects/audio-engine/ audio-engine project page] The closed-source software synthesizer has been replaced by a new synthesizer developed specifically for OpenJDK called Gervill,{{cite web

|url = https://gervill.dev.java.net/

|archive-url = https://archive.today/20111004052704/https://gervill.dev.java.net/

|url-status = dead

|archive-date = 2011-10-04

|title = Gervill - Software Synthesizer

|access-date = 2008-06-01

}}

• All cryptography classes used in the Class library have been released as free software,{{cite web

|url=http://mail.openjdk.java.net/pipermail/security-dev/2007-September/000015.html

|title=Crypto has been added to OpenJDK

|date=2007-09-27

|access-date=2007-10-07

}}

• FreeType has replaced the code that scales and rasterizes fonts.[http://openjdk.java.net/projects/font-scaler/ font-scaler projectpage][http://openjdk.java.net/groups/2d/ Java2D project page]

{{cite web

|url=http://mail.openjdk.java.net/pipermail/font-scaler-dev/2007-August/000011.html

|title=Freetype font rasteriser

|date=2007-08-07

|access-date=2007-11-24

}}

• LittleCMS has replaced the native color-management system. There is a pluggable layer in the JDK, so that the commercial version can use the old color management system and OpenJDK can use LittleCMS.
• The open-sourced Pisces renderer used in the phoneME project has replaced the anti-aliasing graphics rasterizer code.[https://phoneme.dev.java.net/ phoneme.dev.java.net/] {{webarchive|url=https://web.archive.org/web/20070610234355/https://phoneme.dev.java.net/ |date=2007-06-10 }}

[http://openjdk.java.net/projects/graphics-rasterizer/ graphics-rasterizer project page] This code is fully functional, but still needs some performance enhancements,{{cite web

| url=http://mail.openjdk.java.net/pipermail/2d-dev/2007-October/000078.html

| title=Open Source rasterizer

| publisher=Sun Microsystems

|last=Graham|first=Jim

| date=2007-10-03

| access-date=2007-05-09}}

• The JavaScript plugin has been open-sourced (the JavaScript engine itself was open-sourced from the beginning).{{cite web

| url=http://icedtea.classpath.org/bugzilla/show_bug.cgi?id=85

| title=Javascript is encumbered and there is no javascript plugin support.

| publisher=IcedTea

| quote=Changing Summary. JavaScript is no longer encumbered, but we still need liveconnect support.

| date=2008-03-11

| access-date=2008-06-01

| archive-date=2008-09-27

| archive-url=https://web.archive.org/web/20080927185957/http://icedtea.classpath.org/bugzilla/show_bug.cgi?id=85

| url-status=dead

}}

Because of these previously encumbered components, it was not possible to build OpenJDK only with free software components. In order to be able to do this before the whole class library is made free, and to be able to bundle OpenJDK in Fedora Core and other free Linux distributions, Red Hat has started a project called IcedTea. It is basically an OpenJDK/GNU Classpath hybrid that can be used to bootstrap OpenJDK using only free software.{{cite web

| url=http://article.gmane.org/gmane.comp.java.openjdk.distro-packaging.devel/5

| archive-url=https://web.archive.org/web/20080211190907/http://article.gmane.org/gmane.comp.java.openjdk.distro-packaging.devel/5

| url-status=dead

| archive-date=2008-02-11

| title=Experimental Build Repository at icedtea.classpath.org

| date=2007-06-07

|last=Andrew|first=Haley

| access-date=2007-06-09}}{{cite web

| url=http://developer.classpath.org/pipermail/classpath/2007-June/002109.html

| title=Experimental Build Repository at icedtea.classpath.org

| first=Mark

| last=Wielaard

| date=2007-06-07

| access-date=2007-06-09

| archive-date=2007-06-19

| archive-url=https://web.archive.org/web/20070619012918/http://developer.classpath.org/pipermail/classpath/2007-June/002109.html

| url-status=dead

}}

As of March 2008, the Fedora 9 distribution has been released with OpenJDK 6 instead of the IcedTea implementation of OpenJDK 7. Some of the stated reasons for this change are:

• Sun has replaced most of the encumbrances for which IcedTea was providing replacements (less than 1% of encumbered code remains in the class library, and this code is not necessary to run OpenJDK).
• OpenJDK 6 was a stable branch, whereas OpenJDK 7 was unstable and not expected to ship a stable release until 2009.
• Sun has licensed the OpenJDK trademark for use in Fedora.{{citation needed|reason=non-primary|date=December 2011}}

In June 2008, it was announced that IcedTea 6 (as the packaged version of OpenJDK on Fedora 9) had passed the Technology Compatibility Kit tests and can claim to be a fully compatible Java 6 implementation.{{cite web

|url = http://blog.softwhere.org/archives/196

|title = Java is finally Free and Open

|date = 2008-06-19

|last = Sharples

|first = Rich

|url-status = dead

|archive-url = https://web.archive.org/web/20080620065024/http://blog.softwhere.org/archives/196

|archive-date = 2008-06-20

}}

{{citation needed|reason=non-primary|date=December 2011}}

In September 2013, Azul Systems released Zulu, a free, open source build of OpenJDK for Windows Server and the Microsoft Azure Cloud. Later releases added support for Mac OS X, multiple versions of Linux and the Java Platform, Standard Edition version 8. Zulu is certified compliant with Java SE 8, 7 and 6 using the OpenJDK Community Technology Compatibility Kit.{{Cite web|url=http://www.azulsystems.com/products/zulu|title = Core}}

Amazon have released Amazon Corretto a no-cost, multiplatform, production-ready distribution of the Open Java Development Kit. It is released under GPL v2 with the Classpath Exception. Long-term support versions of Java 8 and Java 11 are available. It was first publicly released on January 31, 2019.{{cite web|access-date=2019-07-25|title=Amazon Corretto 8 Now Generally Available|url=https://aws.amazon.com/blogs/opensource/amazon-corretto-8-generally-available/|date=January 31, 2019|website=Amazon Web Services|author=Arun Gupta}}

In 2017, the Eclipse Foundation released AdoptOpenJDK, now named Adoptium, whose main goal is "to promote and support free and open-source high-quality runtimes and associated technology for use across the Java ecosystem."

{{Portal|Free and open-source software|Computer programming}}

• Java (software platform)
• javac
• HotSpot
• Apache Harmony
• OpenJDK
• GNU Classpath and GCJ
• IcedTea
• JamVM
• IKVM
• List of Java virtual machines
• Comparison of Java virtual machines
• Adoptium

{{Reflist|30em}}

• [https://www.gnu.org/philosophy/java-trap.html Free But Shackled - The Java Trap]
• [http://developer.classpath.org/support/ Escaping the Java Trap: A practical road map to the Free Software and Open Source alternatives]
• [http://www.infoq.com/news/2007/06/openjdk-hybrids Hybrids Combine GNU Classpath and OpenJDK]
• [http://meetings-archive.debian.net/pub/debian-meetings/2007/debconf7/low/115_State_of_the_Coffee_Cup.ogg Hour long 2007 video of a workshop with Sun, GGJ, and GNU Classpath developers]
• [https://web.archive.org/web/20060220174727/http://wiki.debian.org/Java/ResolveJavaNaming Java Trademark Issues]

{{Java Virtual Machine}}

{{Java (Sun)}}

{{DEFAULTSORT:Free Java Implementations}}

Category:Java virtual machine

Category:Free virtualization software