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MAJOR PRODUCTS AND TECHNOLOGIES Programming language See Also: Java programming language Writing in the Java Programming Language is the standard way to produce code that will be deployed as Java Bytecode (though there are compilers available for other languages such as Python and Ruby ). Java Syntax borrows heavily from C and C++ but it eliminates certain low-level constructs such as pointers and has a very simple memory model where every object is Allocated On The Heap and all variables of object types are References . Java has non-object primitive types but everything else is an object. The standard Java libraries provide Wrapper Objects for the Primitive Type s, and since Java SE 5.0 the Java compiler automatically inserts conversions between a wrapper type and its corresponding primitive. Memory management is handled through integrated Automatic Garbage Collection performed by the Java Virtual Machine . Platform See Also: Java platform The Java platform consists of a Java virtual machine and implementations of the standard libraries. In order to allow for different types of system there are now three versions. Sun refer to their implementation of the Java platform as the Java Runtime Environment (JRE).
Java Development Kit See Also: Java Development Kit The Java Development Kit ('''JDK''') is a Sun product aimed at Java developers. Since the introduction of Java, it has been by far the most widely used Java SDK . It contains a Java compiler and a number of other important development tools as well as a full copy of the Java Runtime Environment . HISTORY Early history The Java Platform and language began as an internal project at Sun Microsystems in December of 1990. Engineer Patrick Naughton had become increasingly frustrated with the state of Sun's C++ and C API s (application programming interfaces) and tools. While considering moving to NeXT , Naughton was offered a chance to work on new technology and thus the Stealth Project was started. The Stealth Project was soon renamed to the Green Project with James Gosling and Mike Sheridan joining Naughton. Together with other engineers, they began work in a small office on Sand Hill Road in Menlo Park, California . They were attempting to develop a new technology for programming next generation smart appliances, which Sun expected to be a major new opportunity. The team originally considered using C++, but it was rejected for several reasons. Because they were developing an Embedded System with limited resources, they decided that C++ demanded too large a footprint and that its complexity led to developer errors. The language's lack of Garbage Collection meant that programmers had to manually manage system memory, a challenging and error-prone task. The team was also troubled by the language's lack of portable facilities for security, Distributed Programming , and Thread ing. Finally, they wanted a platform that could be easily ported to all types of devices. Bill Joy had envisioned a new language combining the best of Mesa and C. In a paper called ''Further'', he proposed to Sun that its engineers should produce an Object-oriented environment based on C++. Initially, Gosling attempted to modify and extend C++, which he referred to as C++ ++ --, but soon abandoned that in favor of creating an entirely new language, which he called Oak after the tree that stood just outside his office. The team worked long hours and by the summer of 1992, they were able to demonstrate portions of the new platform including the Green OS , the Oak language, the libraries, and the hardware. Their first attempt, demonstrated on September 3 , 1992 , focused on building a PDA device named Star7 which had a graphical interface and a smart agent called "Duke" to assist the user. In November of that year, the Green Project was spun off to become '''FirstPerson, Inc''', a wholly owned subsidiary of Sun Microsystems, and the team relocated to Palo Alto, California . The FirstPerson team was interested in building highly interactive devices, and when Time Warner issued an RFP for a Set-top Box , FirstPerson changed their target and responded with a proposal for a set-top box platform. However, the Cable industry felt that their platform gave too much control to the user and FirstPerson lost their bid to SGI . An additional deal with The 3DO Company for a set-top box also failed to materialize. Unable to generate interest within the TV industry, the company was rolled back into Sun. Java meets the Internet In June and July of 1994, after a three-day brainstorming session with John Gage , James Gosling , Joy, Naughton, Wayne Rosing , and Eric Schmidt , the team re-targeted the platform for the Web . They felt that with the advent of the Mosaic browser, the Internet was on its way to evolving into the same highly interactive medium that they had envisioned for cable TV. As a prototype, Naughton wrote a small web browser, WebRunner, later renamed HotJava . That year, the language was renamed Java after a Trademark search revealed that the name "Oak" was used by a manufacturer of video adaptor cards. The name Java was coined at a local coffee shop frequented by some of the members. It is not clear whether the name is an acronym or not; although some accounts claim that it stands for the names of '''J'''ames Gosling, '''A'''rthur '''V'''an Hoff, and '''A'''ndy Bechtolsheim, or '''J'''ust '''A'''nother '''V'''ague '''A'''cronym, it is generally accepted that "Java" does not stand for anything. Lending credence to the idea that Java owes its name to the products sold at the coffee shop is the fact that the first 4 bytes (the so-called " Magic Number ") of any Class File are, in Hexadecimal , 0xCAFEBABE. In October of 1994, HotJava and the Java platform was demonstrated for Sun executives. Java 1.0a was made available for download in 1994, but the first public release of Java and the HotJava Web Browser came on May 23 , 1995 , at the SunWorld conference. The announcement was made by John Gage , the Director of Science for Sun Microsystems. His announcement was accompanied by a surprise announcement by Marc Andreessen , Executive Vice President of Netscape , that Netscape would be including Java support in its browsers. On January 9 , 1996 , the JavaSoft business group was formed by Sun Microsystems to develop the technology. {Link without Title} Two weeks later the first version of Java was released. Recent history Web use = Client side The ability of web browsers to run Java Applet s has ensured the continuing use of Java by the general public. Flash is more widespread for simple interactive animations and developers are beginning to apply Ajax techniques in this area too. Java is often applied to more complex applications like Yahoo! Games and more recently, video players from multiple suppliers (e.g. {Link without Title} ). = Server side On the Server side of the Web, Java is more popular than ever, with many websites using JavaServer Pages and other Java-based technologies. Desktop use On the desktop, stand-alone Java applications remain relatively rare for several reasons. {Link without Title}
Standalone applications have fallen out of favor as computing has switched to a Web-based model. New programming techniques have produced powerful Web applications. However, there are some Java applications in fairly widespread use, including the NetBeans and Eclipse Integrated Development Environment s, and file sharing clients such as LimeWire and Azureus . Java is also used in the MATLAB mathematics program for rendering the User Interface and for part of the calculation functionality. Java Swing and SWT desktop applications are being developed as an alternative to Microsoft .NET technology. Java runtime availability A version of the Java Runtime Environment is available on most desktops. Microsoft has not bundled a Java Runtime Environment with its operating systems since before Windows XP was released in 2001, but most manufacturers of Microsoft Windows systems continue to include a JRE when they ship their systems. It is also shipped as standard on Apple's Mac OS X , as well as most Linux Distribution s. Because of incompatibilities between different versions of the JRE, rather than rely on pre-installed JREs, many applications install their own JREs in order to function predictably. Java applets can detect which version of Java they are running on and the high level of compatibility between different versions of Java ensures it is a simple matter to support older versions of Java whilst making use of the additional features of later versions. Version history , first introduced for J2SE 1.3, allows provisioning applications over the Web by clicking a Desktop Icon or a link on a website.]] The Java language has undergone several changes since JDK ( Java Development Kit ) 1.0 as well as numerous additions of classes and packages to the standard Library . Since J2SE 1.4, the evolution of the Java Language has been governed by the Java Community Process (JCP), which uses ''Java Specification Requests'' (JSRs) to propose and specify additions and changes to the Java platform. The language is specified by the ''Java Language Specification'' (JLS); changes to the JLS are managed under JSR 901 .
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