Apache Harmony is an open source implementation of Java, starting with Java SE 5.0. It will be licensed under the Apache License, Version 2. It was announced in early May 2005 and on October 25th 2006, the Board of Directors voted to make Apache Harmony a top-level project. Software development is the translation of a user need or marketing goal into a software product. ... Apache Software Foundation Logo The Apache Softwares Foundation (ASF) is a non-profit corporation (classified as 501(c)(3) in the United States) to support Apache software projects, including the Apache HTTP Server. ... A software release refers to the creation and availability of a new version of a computer software product. ... April 28 is the 118th day of the year (119th in leap years) in the Gregorian calendar, with 247 days remaining. ... 2007 (MMVII) is the current year, a common year starting on Monday of the Gregorian calendar and the Anno Domini (common) era. ... An operating system (OS) is a set of computer programs that manage the hardware and software resources of a computer. ... A cross-platform (or platform independent) programming language, software application or hardware device works on more than one system platform (e. ... Java 1. ... A software license is a legal agreement which may take the form of a proprietary or gratuitous license as well as a memorandum of contract between a producer and a user of computer software. ... The Apache License (Apache Software License previous to version 2. ... A website (or Web site) is a collection of web pages, images, videos and other digital assets and hosted on a particular domain or subdomain on the World Wide Web. ... Open source refers to projects that are open to the public and which draw on other projects that are freely available to the general public. ... Java is an object-oriented applications programming language developed by Sun Microsystems in the early 1990s. ... Java Platform, Standard Edition or Java SE (formerly known up to version 5. ... A software license is a legal agreement which may take the form of a proprietary or gratuitous license as well as a memorandum of contract between a producer and a user of computer software. ... The Apache License (Apache Software License previous to version 2. ... 2005 (MMV) was a common year starting on Saturday of the Gregorian calendar. ...

History

Initiation

The Harmony project was initially conceived as an effort to unite all developers of the Free Java language implementations. Many developers expected that it would be the project above the GNU, Apache and other communities. GNU developers were invited into and participated during the initial, preparatory planning. Later it was decided not to use the code from GNU Classpath, and that Harmony would use an incompatible licence; therefore blocking the sharing of code between Harmony and existing free Java projects. Apache developers would then write the needed classes from scratch and expect necessary large code donations from software companies. A software developer is a person who is concerned with one or more facets of the software development process, a somewhat broader scope of computer programming or a specialty of project managing. ... GNU (pronounced ) is a computer operating system - consisting of a kernel, libraries, system utilities, compilers, and end-user application software - composed entirely of free software. ... Apache Software Foundation Logo The Apache Softwares Foundation (ASF) is a non-profit corporation (classified as 501(c)(3) in the United States) to support Apache software projects, including the Apache HTTP Server. ... GNU Classpath is a project aiming to create a free implementation of the standard class library for the Java programming language. ... The term software company could be applied to; a) a company that produces software or b) a company that distributes software from a third party or c) a company that provides services for software. ...

Reasons for rewriting from scratch

The main reason for disagreements between the GNU Classpath and Apache projects is due to differences between the General Public License (GNU Classpath's license also contains the linking exception) and Apache License. These disagreements are inspired by various organizations and individuals^[1] that prefer the slightly more liberal Apache License that allows for closed source derived works. GNU Classpath can also be linked^[2] with proprietary code, but it is legally difficult to make a closed source derivative of GNU Classpath itself. However, many free software developers think that the licenses and philosophy of these communities are not different enough to split the efforts, and the inability to find compromises is frequently estimated negatively. The occasionally appearing suggestion to view these projects as opposing forces does not find wide support. Enthusiasts of the free software tend to break the discussion with the simple words that "more free software is not a problem"^[3]. GPL redirects here. ... Some free software projects, notably GNU Classpath, distribute code under the terms of the GNU GPL but with the following clarification and special exception: Linking this library statically or dynamically with other modules is making a combined work based on this library. ...

Difficulties to obtain a TCK license from Sun

The Apache Software Foundation sent the following letter to Sun Microsystems CEO, Jonathan Schwartz, on April 10, 2007, regarding their inability to acquire an acceptable license for the Java SE 5 Technology Compatibility Kit (TCK), a test kit needed by the project to demonstrate compatibility with the Java SE 5 specification, as required by the Sun specification license for Java SE 5 ^[4]. What makes the license unacceptable for ASF is the fact that it impose rights restrictions through limits on the "field of use" available to users of Harmony, not compliant with the Java Community Process rules ^[5]. Apache Software Foundation Logo The Apache Softwares Foundation (ASF) is a non-profit corporation (classified as 501(c)(3) in the United States) to support Apache software projects, including the Apache HTTP Server. ... Sun Microsystems, Inc. ... A Chief Executive Officer (CEO), or Chief Executive, is the highest-ranking corporate officer, administrator, corporate administrator, executive, or executive officer, in charge of total management of a corporation, company, organization or agency. ... Jonathan I. Schwartz (born 1967 ? [1]) is the current President and COO of Sun Microsystems. ... April 10 is the 100th day of the year in the Gregorian calendar (101st in leap years). ... A technology compatibility kit (TCK) is a suite of tests that at least nominally checks a particular alleged implementation of a Java Specification Request (JSR) for compliance. ... Sun Microsystems, Inc. ... Apache Software Foundation Logo The Apache Softwares Foundation (ASF) is a non-profit corporation (classified as 501(c)(3) in the United States) to support Apache software projects, including the Apache HTTP Server. ... The Java Community Process or JCP, established in 1995, is a formalized process which allows interested parties to be involved in the definition of future versions and features of the Java platform. ...

Sun answered on a company blog [1][2] that it intended to create an open source implementation of the Java platform under GPL, including the TCK, but that their current priority was to make the Java Platform accessible to the GNU/Linux community under GPL as quickly as possible. The GNU logo For other uses of GPL, see GPL (disambiguation). ... The Java platform is the name for a computing environment, or platform, from Sun Microsystems which can run applications developed using the Java programming language and set of development tools. ... Linux (IPA pronunciation: ) is a Unix-like computer operating system family. ... The GNU logo For other uses of GPL, see GPL (disambiguation). ...

This answer triggered some reactions, either criticizing Sun for not responding in a sufficient open manner to an open letter [3], or rather Apache Software Foundation; some think that ASF acted unwise to ask aggressively for something they could obtain with more diplomacy from Sun, especially considering the timescale of the opening class library [4] [5] . Sun Microsystems, Inc. ... Apache Software Foundation Logo The Apache Softwares Foundation (ASF) is a non-profit corporation (classified as 501(c)(3) in the United States) to support Apache software projects, including the Apache HTTP Server. ...

Development team

Apache Harmony started from being mostly developed by several companies, receiving large code contributions at once. However the general discussions on the mailing lists were always opened for everyone, and later the Apache Software foundation mentors put a lot of effort ^[6] to bring the development process more in line with the Apache way ^[7], and it seems that their efforts were highly successful. In November 1, 2006, the current team of committers consisted of 16 developers, 12 of them from IBM and Intel ^[8]. November 1 is the 305th day of the year (306th in leap years) in the Gregorian Calendar, with 60 days remaining. ... For the Manfred Mann album, see 2006 (album). ...

Recent development status

Apache Harmony has been accepted among the official Apache projects on 29th October 2006.

Library Coverage

The expected donations from software companies were actually received. The Apache Harmony now contains the working code, including the Swing, AWT and Java 2D code which were contributed by Intel. Example Swing widgets in Java 5. ... The Abstract Windowing Toolkit (AWT) is Javas platform_independent windowing, graphics, and user_interface widget toolkit. ... In computing, Java 2D is an API for drawing two-dimensional graphics using the Java programming language. ... Intel Corporation (NASDAQ: INTC, SEHK: 4335), founded in 1968 as Integrated Electronics Corporation, is an American multinational corporation that is best known for designing and manufacturing microprocessors and specialized integrated circuits. ...

The part of the implemented classes is still smaller than in GNU Classpath (96% in the trunk versus almost 100% as of November 2006 ^[9]), despite some non-trivial applications were shown being running in 2006 JavaONE international conference. GNU Classpath is a project aiming to create a free implementation of the standard class library for the Java programming language. ... It has been suggested that this article or section be merged into Trunk build. ... For the Manfred Mann album, see 2006 (album). ... JavaOne is an annual conference (since 1996) put on by Sun Microsystems to discuss Java technologies, primarily among Java developers. ...

Also Harmony's test suite is less extensive than GNU Classpath's for now (20000 tests [6] versus 50000 [7] as of October 2006). GNU Classpath is a project aiming to create a free implementation of the standard class library for the Java programming language. ...

The progress of the Apache Harmony project can be tracked against J2SE 1.4^[10] and Java SE 5.0^[11].

Documentation

Harmony is currently less documented than the alternative free java implementations. For instance, in GNU Classpath every method of the central CORBA class (ORB) has the explaining comment both in the standard abstract API class [8] and implementation [9]. In the Yoko project, used by Harmony [10], the majority of methods both in the standard declaration [11] and implementing class [12] were not documented (at the end of October, 2006). Also, GNU Classpath supported both older and current CORBA features (same as Sun's implementation). Harmony, differently, left the central method of the older standard (ORB.connect(Object)) fully unimplemented. In computing, Common Object Request Broker Architecture (CORBA) is a standard for software componentry, created and controlled by the Object Management Group (OMG). ...

Tools

A complete implementation of the Java platform also requires a compiler that translates Java source code into bytecodes, a program that manages JAR files, a debugger, and an applet viewer and web browser plugin, to name a few. Harmony currently only has the compiler [13]. This article is about the computing term. ... Bytecode is a binary representation of an executable program designed to be executed by a virtual machine rather than by dedicated hardware. ... In computing, a Jar file (short for Java archive) is a ZIP file used to distribute a set of Java classes. ... Debug redirects here. ... An applet is a software component that runs in the context of another program, for example a web browser. ... An example of a web browser (Internet Explorer), displaying the English Wikipedia main page. ... A plugin (plug-in, addin, add-in, addon or add-on) is a computer program that interacts with a main (or host) application (a web browser or an email program, for example) to provide a certain, usually very specific, function on demand. ...

However incompleteness of the implementation cannot be a serious criticism for such project, as it is still very young.

Virtual machine support

Harmony currently has four virtual machine implementations, all of which were donations by external groups: In computer science, a virtual machine is software that creates a virtualized environment between the computer platform and its operating system, so that the end user can operate software on an abstract machine. ...

• JC Harmony Edition VM, "JCHEVM," based on the JCVM's interpreter, contributed by the author, Archie Cobbs.
• BootJVM, a simple bootstrapping virtual machine, contributed by Daniel Lydick.
• SableVM, an advanced, portable interpreter, contributed by authors from the Sable Research Group; and the Dynamic Runtime Layer Virtual Machine.
• DRLVM, a just-in-time compiler contributed by Intel.
• BEA announced the availability of an evaluation version of JRockit VM running Apache Harmony Class Library ^[12].

In the end of November, 2006, the language support provided by these virtual machine was still incomplete, and the build instructions recommended to use IBM's proprietary J9 instead to run the class library test suite [14]. JC virtual machine [1] is a java virtual machine that convers class files from byte-code into C and compile them using C compiler GCC. It uses Soot, a Java language framework to load, manipulate and optimize byte-code and GNU classpath as a standard library. ... An interpreter is a computer program that executes other programs. ... In computing, Bootstrapping refers to a process where a simple system activates another more complicated system that serves the same purpose. ... SableVM is a clean room implementation of Java bytecode interpreter implementing the Java virtual machine specification, second edition. ... The Sable Research Group is located at the School of Computer Science at McGill University and currently under the supervision of Laurie Hendren and Clark Verbrugge. ... See also Just in time for the business technique In computing, just-in-time compilation (JIT), also known as dynamic translation, is a technique for improving the performance of interpreted programs. ... Intel Corporation (NASDAQ: INTC, SEHK: 4335), founded in 1968 as Integrated Electronics Corporation, is an American multinational corporation that is best known for designing and manufacturing microprocessors and specialized integrated circuits. ... International Business Machines Corporation (known as IBM or Big Blue; NYSE: IBM) is a multinational computer technology and consulting corporation headquartered in Armonk, New York, USA. The company is one of the few information technology companies with a continuous history dating back to the 19th century. ... Proprietary software is software with restrictions on using, copying and modifying as enforced by the proprietor. ...

However, the DRLVM virtual machine is currently (as of November, 2006) under heavy development, so a fast improvement of its features can be expected. In computer science, a virtual machine is software that creates a virtualized environment between the computer platform and its operating system, so that the end user can operate software on an abstract machine. ...

Applications status

Since its conception, Harmony has steadily grown in its ability to execute non-trivial Java applications (see here). As of December 2006, supported applications include:

• Eclipse : 96% of the 36000 RI test pass on Harmony's DRLVM + class library. [15].
• Apache Tomcat : 100% of the RI tests pass [16].
• JUnit : 100% of the of the RI tests pass [17].
• Apache Ant : 97% of the RI tests pass. [18].
• other applications pass with a high success rate, as Apache Derby, Apache Axis, Log4j, Apache Velocity, Apache Cocoon, jEdit, or Apache Commons.

However, Harmony's incomplete library prevents it from launching some other applications: Eclipse is an open source platform-independent software framework for delivering what the project calls rich-client applications, as opposed to thin client browser-based applications. ... In computing, a reference implementation (or, infrequently, sample implementation) is a software example of a standard for use in helping others implement their own versions of the standard. ... Apache Tomcat is a web container developed at the Apache Software Foundation (ASF). ... In computing, a reference implementation (or, infrequently, sample implementation) is a software example of a standard for use in helping others implement their own versions of the standard. ... JUnit is a unit testing framework for the Java programming language. ... In computing, a reference implementation (or, infrequently, sample implementation) is a software example of a standard for use in helping others implement their own versions of the standard. ... Apache Ant is a software tool for automating software build processes. ... In computing, a reference implementation (or, infrequently, sample implementation) is a software example of a standard for use in helping others implement their own versions of the standard. ... Apache Derby is a Java-based Relational Database Management System that can be embedded in Java programs and used for online transaction processing (OLTP). ... Apache Axis is an open source, Java and XML based Web service framework consisting of an implementation of the SOAP server, and various utilities and APIs for generating and deploying Web service applications. ... . The initial letter is shown capitalized due to technical restrictions. ... This article is about Velocity as template engine. ... Apache Cocoon, often just called Cocoon, is a web development framework built around the concepts of separation of concerns and component-based web development. ... jEdit is a text editor for programmers available under the GNU General Public License. ... The Jakarta Commons is a subproject of the Jakarta Project under the umbrella of the Apache Software Foundation. ...

• ArgoUML: because it requires a Java applet implementation, which is still not available in Harmony.
• Geronimo Application Server, because it requires unimplemented CORBA classes.
• Azureus, because of unimplemented security classes.

ArgoUML is a UML diagramming application written in Java and released under the open source BSD License. ... A Java applet is an applet delivered in the form of Java bytecode. ... The Geronimo project is a free software application server developed by the Apache Software Foundation and distributed under the Apache license. ... In computing, Common Object Request Broker Architecture (CORBA) is a standard for software componentry, created and controlled by the Object Management Group (OMG). ... This article is about a BitTorrent client. ...

See also

• GNU Classpath
• List of Java virtual machines
• Free Java implementations

GNU Classpath is a project aiming to create a free implementation of the standard class library for the Java programming language. ... This is a list of Java Virtual Machines. ... Free Java implementations are software projects that reimplement Suns Java technologies and are distributed under free software licences, thus making them free software / open source software. ...

References

1. ^ Mark Wielaard (2006-05-24). Toward a free Java. LWN.net.
2. ^ GNU Classpath License.
3. ^ Dalibor Topic (2006-06-01). Harmony, JavaONE 2007 and other thoughts.
4. ^ Open Letter to Sun Microsystems
5. ^ According to ASF, 1) a specification lead cannot impose any contractual condition or covenant that would limit or restrict the right of any licensee to create or distribute such Independent Implementations (section 5.C.III), and 2) a specification lead must license all necessary IP royalty-free to any compatible implementation of a specification (section 5.B).
6. ^ Leo Simons (2006-07-24). "We would like all the development to happen right here".
7. ^ The Apache Way.
8. ^ List of Apache Harmony Committers.
9. ^ that a class is implemented does not imply that this class behaves as requested in the RI specification. For example, some implemented methods can still do nothing at all (this is also true for GNU Classpath)
10. ^ Apache Harmony Library Coverage against J2SE 1.4
11. ^ Apache Harmony Library Coverage against Java SE 5.0
12. ^ BEA JRockit VM under a binary, evaluation-only license

For the Manfred Mann album, see 2006 (album). ... May 24 is the 144th day of the year in the Gregorian calendar (145th in leap years). ... LWN.net is a computing news site with an emphasis on Free/Libre/Open-Source Software and software for Unix-like operating systems. ... For the Manfred Mann album, see 2006 (album). ... June 1 is the 152nd day of the year in the Gregorian calendar (153rd in leap years), with 213 days remaining. ... For the Manfred Mann album, see 2006 (album). ... July 24 is the 205th day (206th in leap years) of the year in the Gregorian calendar, with 160 days remaining. ... In computing, a reference implementation (or, infrequently, sample implementation) is a software example of a standard for use in helping others implement their own versions of the standard. ... GNU Classpath is a project aiming to create a free implementation of the standard class library for the Java programming language. ...

External links

• Apache Harmony Web Page
• Apache Harmony FAQ
• Apache Harmony source code repository
• JavaOne 2006 Online Harmony Session
• Apache Harmony by Geir Magnusson at Javapolis 2006
• The Java open source debate - a good summary of the debate