Kaffe is a discontinued "

clean room design Clean-room design (also known as the Chinese wall technique) is the method of copying a design by reverse engineering and then recreating it without infringing any of the copyrights associated with the original design. Clean-room design is usef ...

" ( reverse engineering) version of a Java Virtual Machine. It comes with a subset of the

Java Platform, Standard Edition Java Platform, Standard Edition (Java SE) is a computing platform for development and deployment of portable code for desktop and server environments. Java SE was formerly known as Java 2 Platform, Standard Edition (J2SE). The platform uses Ja ...

(Java SE),

Java API There are two types of Java programming language application programming interfaces (APIs): * The official core Java API, contained in the Android (Google), SE (OpenJDK and Oracle), MicroEJ. These packages (java.* packages) are the core Java la ...

, and

tool A tool is an object that can extend an individual's ability to modify features of the surrounding environment or help them accomplish a particular task. Although many animals use simple tools, only human beings, whose use of stone tools dates ba ...

s needed to provide a

Java Java (; id, Jawa, ; jv, ꦗꦮ; su, ) is one of the Greater Sunda Islands in Indonesia. It is bordered by the Indian Ocean to the south and the Java Sea to the north. With a population of 151.6 million people, Java is the world's mos ...

runtime environment. Like most other Free Java virtual machines, Kaffe uses

GNU Classpath GNU Classpath is a free software implementation of the standard class library for the Java programming language. Most classes from J2SE 1.4 and 5.0 are implemented. Classpath can thus be used to run Java-based applications. GNU Classpath is a p ...

as its

class library In computer science, a library is a collection of non-volatile resources used by computer programs, often for software development. These may include configuration data, documentation, help data, message templates, pre-written code and subro ...

. Kaffe, first released in 1996, was the original open-source Java implementation. Initially developed as part of another project, it grew so popular that developers Tim Wilkinson and Peter Mehlitz founded Transvirtual Technologies, Inc. with Kaffe as the company's flagship product. In July 1998, Transvirtual released Kaffe OpenVM under a

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 to run, study, share, and modify the software. The license was the first copyleft for general ...

. Kaffe is a lean and portable

virtual machine In computing, a virtual machine (VM) is the virtualization/ emulation of a computer system. Virtual machines are based on computer architectures and provide functionality of a physical computer. Their implementations may involve specialized h ...

, although it is significantly slower than commercial implementations. When compared to the reference implementation of the Java Virtual Machine written by Sun Microsystems, Kaffe is significantly smaller; it thus appeals to

embedded system An embedded system is a computer system—a combination of a computer processor, computer memory, and input/output peripheral devices—that has a dedicated function within a larger mechanical or electronic system. It is ''embedded'' ...

developers. It comes with just-in-time

compilers In computing, a compiler is a computer program that translates computer code written in one programming language (the ''source'' language) into another language (the ''target'' language). The name "compiler" is primarily used for programs that ...

for many of the

CPU architecture Processor design is a subfield of computer engineering and electronics engineering (fabrication) that deals with creating a processor, a key component of computer hardware. The design process involves choosing an instruction set and a certain ...

s, and has been

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 H ...

ed to more than 70

system platform A computing platform or digital platform is an environment in which a piece of software is executed. It may be the hardware or the operating system (OS), even a web browser and associated application programming interfaces, or other underlying so ...

s in total. It runs on devices ranging from embedded

SuperH SuperH (or SH) is a 32-bit reduced instruction set computing (RISC) instruction set architecture (ISA) developed by Hitachi and currently produced by Renesas. It is implemented by microcontrollers and microprocessors for embedded systems. At the ...

devices to

IBM zSeries IBM Z is a family name used by IBM for all of its z/Architecture mainframe computers. In July 2017, with another generation of products, the official family was changed to IBM Z from IBM z Systems; the IBM Z family now includes the newest mod ...

mainframe computers, and it will even run on a PlayStation 2. Unlike other implementations, in the past Kaffe used GNU Multi-Precision Library (GMP) to support arbitrary precision arithmetics. This feature has been removed from release 1.1.9, causing protests from people that claim they used Kaffe for the sole reason GMP arithmetic being faster than the typical pure java implementation, available in other distributions. The capability was removed to reduce the maintenance work, expecting that interested people will integrate GMP support into

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 w ...

. Subsequently GNU Classpath introduced GMP support in version 0.98.

References

External links

*
Transvirtual Adopts Microsoft Java Extensions, October 1st, 1999 by Craig Knudsen
{{Java (software platform) Discontinued Java virtual machines Free compilers and interpreters

See also

References

External links