WHAT IS JAVA

WHAT IS JAVA

Java?is a?high-level ,?class-based ,?object-oriented ?programming language ?that is designed to have as few implementation?dependencies ?as possible. It is a?general-purpose ?programming language intended to let?programmers ?write once, run anywhere?(WORA ),[17] ?meaning that?compiled ?Java code can run on all platforms that support Java without the need to recompile.[18] ?Java applications are typically compiled to?bytecode ?that can run on any?Java virtual machine ?(JVM) regardless of the underlying?computer architecture . The?syntax ?of Java is similar to?C ?and?C++ , but has fewer?low-level ?facilities than either of them. The Java runtime provides dynamic capabilities (such as?reflection ?and runtime code modification) that are typically not available in traditional compiled languages. As of 2019, Java was one of the most?popular programming languages in use ?according to?GitHub ,[citation not found ][19] [20] ?particularly for?client–server ?web applications , with a reported 9 million developers.[21]

Java was originally developed by?James Gosling ?at?Sun Microsystems . It was released in May 1995 as a core component of Sun Microsystems'?Java platform . The original and?reference implementation ?Java?compilers , virtual machines, and?class libraries ?were originally released by Sun under?proprietary licenses . As of May 2007, in compliance with the specifications of the?Java Community Process , Sun had?relicensed ?most of its Java technologies under the?GPL-2.0-only ?license.?Oracle ?offers its own?HotSpot ?Java Virtual Machine, however the official?reference implementation ?is the?OpenJDK ?JVM which is free open-source software and used by most developers and is the default JVM for almost all Linux distributions.

As of March?2023,?Java?20 ?is the latest version, while Java 17, 11 and 8 are the current?long-term support ?(LTS) versions.

Sun Microsystems released the first public implementation as Java 1.0 in 1996.[26] ?It promised?write once, run anywhere ?(WORA) functionality, providing no-cost run-times on popular?platforms . Fairly secure and featuring configurable security, it allowed network- and file-access restrictions. Major?web browsers ?soon incorporated the ability to run?Java applets ?within web pages, and Java quickly became popular. The Java 1.0 compiler was re-written?in Java ?by?Arthur van Hoff ?to comply strictly with the Java 1.0 language specification.[27] ?With the advent of Java 2 (released initially as J2SE 1.2 in December 1998?– 1999), new versions had multiple configurations built for different types of platforms.?J2EE ?included technologies and APIs for enterprise applications typically run in server environments, while J2ME featured APIs optimized for mobile applications. The desktop version was renamed J2SE. In 2006, for marketing purposes, Sun renamed new J2 versions as?Java EE ,?Java ME , and?Java SE , respectively.

In 1997, Sun Microsystems approached the?ISO/IEC JTC 1 ?standards body and later the?Ecma International ?to formalize Java, but it soon withdrew from the process.[28] [29] [30] ?Java remains a?de facto?standard , controlled through the?Java Community Process .[31] ?At one time, Sun made most of its Java implementations available without charge, despite their?proprietary software ?status. Sun generated revenue from Java through the selling of licenses for specialized products such as the Java Enterprise System.

On November 13, 2006, Sun released much of its Java virtual machine (JVM) as?free and open-source software ?(FOSS), under the terms of the?GPL-2.0-only ?license. On May 8, 2007, Sun finished the process, making all of its JVM's core code available under?free software /open-source distribution terms, aside from a small portion of code to which Sun did not hold the copyright.[32]

Sun's vice-president Rich Green said that Sun's ideal role with regard to Java was as an?evangelist.[33] ?Following?Oracle Corporation 's acquisition of Sun Microsystems in 2009–10, Oracle has described itself as the steward of Java technology with a relentless commitment to fostering a community of participation and transparency.[34] ?This did not prevent Oracle from filing a lawsuit against Google shortly after that for using Java inside the?Android SDK ?(see the?Android ?section).

On April 2, 2010, James Gosling resigned from?Oracle .[35]

In January 2016, Oracle announced that Java run-time environments based on JDK 9 will discontinue the browser plugin.[36]

Java software runs on everything from laptops to?data centers ,?game consoles ?to scientific?supercomputers .[37]

Oracle ?(and others) highly recommend uninstalling outdated and unsupported versions of Java, due to unresolved security issues in older versions.[38]

Principles

There were five primary goals in the creation of the Java language:[18]

  1. It must be simple,?object-oriented , and familiar.
  2. It must be?robust ?and secure.
  3. It must be architecture-neutral and portable.
  4. It must execute with high performance.
  5. It must be?interpreted ,?threaded , and?dynamic .

Versions

Main article:?Java version history

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