The Java Class Library is a set of dynamically loadable libraries that Java applications can call at runtime. Because the Java Platform is not dependent on any specific operating system, applications cannot rely on any of the existing libraries. Instead, the Java Platform provides a comprehensive set of standard class libraries, containing much of the same reusable functions commonly found in modern operating systems. Illustration of an application which may use libvorbisfile. ... Java is an object-oriented applications programming language developed by Sun Microsystems in the early 1990s. ... 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. ... In C++, the Standard Library is a collection of classes and functions, which are written in the core language. ...

The Java class libraries serve three purposes within the Java Platform:

• Like other standard code libraries, they provide the programmer a well-known set of functions to perform common tasks, such as maintaining lists of items or performing complex string parsing.
• In addition, the class libraries provide an abstract interface to tasks that would normally depend heavily on the hardware and operating system. Tasks such as network access and file access are often heavily dependent on the native capabilities of the platform.
• Finally, some underlying platforms may not support all of the features a Java application expects. In these cases, the class libraries can either emulate those features using whatever is available, or provide a consistent way to check for the presence of a specific feature.

In C++, the Standard Library is a collection of classes and functions, which are written in the core language. ... In object-oriented programming, a collection class is any class that is capable of storing other objects. ... In computing, a regular expression is a string that is used to describe or match a set of strings, according to certain syntax rules. ... This article or section is in need of attention from an expert on the subject. ... A computer file is a collection of information that is stored in a computer system and can be identified by its full path name. ...

Architecture

The Java Class Library is almost entirely written in Java itself, except the parts that need to have direct access to the hardware and operating system (as for I/O, or Graphic Rasterisation). The Java classes that give access to these functions commonly use JNI wrappers to access the native API of the operating system. Hardware is the general term that is used to describe physical artifacts of a technology. ... An operating system (OS) is a set of computer programs that manage the hardware and software resources of a computer. ... Energy Input: The energy placed into a reaction. ... Rasterization or rasterisation is the task of taking an image described in a vector graphics format (shapes) and converting it into a raster image (pixels or dots) for output on a video display or printer. ... The Java Native Interface (JNI) is a programming framework that allows Java code running in the Java virtual machine (VM) to call and be called by native applications (programs specific to a hardware and operating system platform) and libraries written in other languages, such as C, C++ and assembly. ...

Mostly all the Java classes of the library are contained in a single Jar file contained in the JRE or JDK distribution, called rt.jar. Contrary to other libraries used by an application, the Class Library contained in rt.jar is in the default Bootstrap Classpath ^[1], and so does not have to be included in the Classpath declared for the application. In computing, a JAR file (or Java ARchive) file used to distribute a set of Java classes. ... The Java Runtime Environment, or JRE, is a software bundle from Sun Microsystems that allows a computer system to run a Java application. ... The Java Development Kit (JDK) is a Sun Microsystems product aimed at Java developers. ... The Classpath is an argument set on the command-line that tells the Java Virtual Machine where to look for user-defined classes and packages in Java programs. ...

Conformance

Any Java implementation must pass the Java Technology Compatibility Kit tests for compliance. 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. ...

Main Features

Main article: Java Platform, Standard Edition

Features of the Class Library are accessed through classes grouped by packages. Java Platform, Standard Edition or Java SE (formerly known up to version 5. ... In object-oriented programming, a class is a programming language construct that is used to group related instance variables and methods. ... A Java package is a Java programming language mechanism for organizing classes into namespaces. ...

• java.lang contains fundamental classes and interfaces closely tied to the language and runtime system.
• I/O and networking: access to the platform File system, and more generally to networks is provided through the java.io, java.nio, and java.net packages.
• Mathematic package: the java.math provide regular mathematical expressions, as well as arbitrary-precision decimals and integers numbers.
• Collections and Utilities : provide built-in Collection data structures, and various utility classes, for Regular expressions, Concurrency, logging and Data compression.
• GUI and 2D Graphics: the java.awt package support basic GUI operations and binds to the underlying native system. It also contains the 2D Graphics API. The javax.swing package is built on awt and provide a platform independent widget toolkit, as well as a Pluggable look and feel. It also deals with editable and non editable text components.
• Sound: provides interfaces and classes for reading, writing, sequencing, and synthesizing of Sound data.
• Text: the java.text package deals with text, dates, numbers, and messages.
• Image package: java.awt.image and javax.imageio provide APIs to write, read, and modify images.
• XML: built-in classes handle SAX, DOM, StAX, XSLT transforms, XPath, and various APIs for Web services, as SOAP protocol and JAX-WS.
• CORBA and RMI APIs, including a built-in ORB
• Security and Cryptography
• Databases: access to SQL databases is provided through the java.sql package.
• Access to Scripting engines: the javax.script package give an API to access any Scripting language that conform to this API.
• Applets: java.applet allows applications to be downloaded over a network and run within a guarded sandbox
• Java Beans: java.beans provide ways to manipulate reusable components.

It has been suggested that this article or section be merged into Protocol (object-oriented programming). ... The Java Runtime Environment, or JRE, is a software bundle from Sun Microsystems that allows a computer system to run a Java application. ... Energy Input: The energy placed into a reaction. ... This article or section is in need of attention from an expert on the subject. ... In computing, a file system (often also written as filesystem) is a method for storing and organizing computer files and the data they contain to make it easy to find and access them. ... “Computer Networks” redirects here. ... java. ... In object-oriented programming, a collection class is any class that is capable of storing other objects. ... A binary tree, a simple type of branching linked data structure. ... In computing, a regular expression is a string that is used to describe or match a set of strings, according to certain syntax rules. ... Concurrent computing is the concurrent (simultaneous) execution of multiple interacting computational tasks. ... This article or section does not cite any references or sources. ... In computer science and information theory, data compression or source coding is the process of encoding information using fewer bits (or other information-bearing units) than an unencoded representation would use through use of specific encoding schemes. ... GUI can refer to the following: GUI is short for graphical user interface, a term used to describe a type of interface in computing. ... 2D computer graphics is the computer-based generation of digital images—mostly from two-dimensional models (such as 2D geometric models, text, and digital images) and by techniques specific to them. ... The Abstract Windowing Toolkit (AWT) is Javas platform_independent windowing, graphics, and user_interface widget toolkit. ... In computer programming, widget toolkits (or GUI toolkits) are sets of basic building units for graphical user interfaces. ... Pluggable look and feel is a mecanism used in some Widget toolkits allowing to change the look and feel of a graphical user interface at runtime. ... In the field of electronic music, a sequencer was originally any device that recorded and played back a sequence of control information for an electronic musical instrument. ... A synthesizer (or synthesiser) is an electronic musical instrument designed to produce electronically generated sound, using techniques such as additive, subtractive, FM, physical modelling synthesis, phase distortion, or Scanned synthesis. ... The Extensible Markup Language (XML) is a general-purpose markup language. ... SAX is a serial access parser API for XML. SAX provides a mechanism for reading data from an XML document. ... Document Object Model (DOM) is a platform- and language-independent standard object model for representing HTML or XML and related formats. ... Streaming API for XML (StAX) is an application programming interface (API) to read and write XML documents in the Java programming language. ... Diagram of the basic elements and process flow of Extensible Stylesheet Language Transformations. ... XPath (XML Path Language) is an expression language for addressing portions of an XML document, or for computing values (strings, numbers, or boolean values) based on the content of an XML document. ... The W3C defines a Web service[1] as a software system designed to support interoperable Machine to Machine interaction over a network. ... This article is about the computer protocol. ... The Common Object Request Broker Architecture (CORBA) is a standard defined by the Object Management Group (OMG) that enables software components written in multiple computer languages and running on multiple computers to interoperate. ... A typical implementation model of Java-RMI using Stub and Skeleton objects. ... In distributed computing, an object request broker (ORB) is a piece of middleware software that allows programmers to make program calls from one computer to another, via a network. ... In computing , a database can be defined as a structured collection of records or data that is stored in a computer so that a program can consult it to answer queries. ... The related Category:SQL statements has been nominated for deletion, merging, or renaming. ... Scripting languages (commonly called scripting programming languages or script languages) are computer programming languages that are typically interpreted and can be typed directly from a keyboard. ... A Java applet is an applet delivered in the form of Java bytecode. ... JavaBeans are classes written in the Java programming language. ...

Licensing

Following their promise to release a fully buildable JDK based almost completely on free and open source code in the first half of 2007 [1], 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 and open-source license ^[2]. Sun's goal is to replace the parts that remain proprietary and closed source with alternative implementations and make the class library completely free and open source.^[3]. The Java Development Kit (JDK) is a Sun Microsystems product aimed at Java developers. ... 2007 (MMVII) is the current year, a common year starting on Monday of the Gregorian calendar and the AD/CE era. ... Source code (commonly just source or code) is any series of statements written in some human-readable computer programming language. ... May 8 is the 128th day of the year in the Gregorian calendar (129th in leap years). ... 2007 (MMVII) is the current year, a common year starting on Monday of the Gregorian calendar and the AD/CE era. ...

As of May 2007, The parts of the Class library that remain proprietary and closed-source (4% as of May 2007 ^[4]) are: This article does not cite any references or sources. ... 2007 (MMVII) is the current year, a common year starting on Monday of the Gregorian calendar and the AD/CE era. ...

• some parts of the audio-engine code (connection to underlying audio systems, and some implementations of higher level functionalities, such as a MIDI synthesizer) [2].
• the code that scale and rasterize fonts (Sun plan to use FreeType as a replacement) [3] [4].
• some parts of the anti-aliasing graphics rasterizer code (one of the possible free and open-source candidates is the Pisces renderer used in the phoneME project) [5] [6].
• the native color management system (Sun plan to use LittleCMS as a replacement) [7].
• some parts of the cryptography extensions used in the Class library, as some providers (as JCE) who makes calls to underlying cryptography implementations [8].

MIDI (Musical Instrument Digital Interface) is an industry-standard electronic communications protocol that enables electronic musical instruments, computers and other equipment to communicate, control and synchronize with each other in real time. ... Rasterization or rasterisation is the task of taking an image described in a vector graphics format (shapes) and converting it into a raster image (pixels or dots) for output on a video display or printer. ... In typography, a typeface is a co-ordinated set of character designs, which usually comprises an alphabet of letters, a set of numerals and a set of punctuation marks. ... FreeType is a software library that implements a font engine. ... In digital signal processing, anti-aliasing is the technique of minimizing aliasing (jagged or blocky patterns) when representing a high-resolution signal at a lower resolution. ... Rasterization or rasterisation is the task of taking an image described in a vector graphics format (shapes) and converting it into a raster image (pixels or dots) for output on a video display or printer. ... Color management is a term used in computer environments which describes a controlled conversion between the colors of various color devices, such as scanners, digital cameras, monitors, TV screens, film printers, printers, offset presses, and corresponding media. ... The subject of this article seems to fail one of the following consensually-accepted Wikipedia inclusion guidelines: If you are familiar with the subject matter, please expand the article to establish its notability, citing reliable sources, so as to avoid it being considered for deletion. ... The German Lorenz cipher machine, used in World War II for encryption of very high-level general staff messages Cryptography (or cryptology; derived from Greek κρυπτός kryptós hidden, and the verb γράφω gráfo write) is the study of message secrecy. ...

Alternative implementations

GNU Classpath is the other main free software class library for Java. Contrary to other implementations, it only implement the Class Library, and is used by many free Java runtimes (like Kaffe, SableVM, JamVM, CACAO). GNU Classpath is a project aiming to create a free implementation of the standard class library for the Java programming language. ... 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. ... Kaffe is a clean room design of a Java Virtual Machine. ... SableVM is a clean room implementation of Java bytecode interpreter implementing the Java virtual machine specification, second edition. ... JamVM [1] is an open-source Java virtual machine developed to be extremely small compared with other VMs while conforming to the Java virtual machine specification version 2 (blue book). ... Binomial name Theobroma cacao L. Cacao (Theobroma cacao) is a small (4–8 m tall) evergreen tree in the family Sterculiaceae (alternatively Malvaceae), native to tropical Mexico, but now cultivated throughout the tropics. ...

Apache Harmony is another free software class library. Its aim is to also implement the other parts of the Java stack (Virtual Machine, Compiler, and other tools required for any Java implementation). Apache Harmony is an open source implementation of Java, starting with Java SE 5. ... A Java Virtual Machine (JVM), originally developed by Sun Microsystems, is a virtual machine that executes Java bytecode. ... It has been suggested that this article or section be merged into Java programming language. ... 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. ^ How Classes are Found
2. ^ Open JDK is here!. Sun Microsystems (2007-05-08). Retrieved on 2007-05-09.
3. ^ 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
4. ^ Fitzsimmons, Thomas (2007-05-18). Plans for OpenJDK. Retrieved on 2007-05-22.

2007 (MMVII) is the current year, a common year starting on Monday of the Gregorian calendar and the AD/CE era. ... May 8 is the 128th day of the year in the Gregorian calendar (129th in leap years). ... 2007 (MMVII) is the current year, a common year starting on Monday of the Gregorian calendar and the AD/CE era. ... May 9 is the 129th day of the year (130th in leap years) in the Gregorian calendar. ... The text below is generated by a template, which has been proposed for deletion. ... 2007 (MMVII) is the current year, a common year starting on Monday of the Gregorian calendar and the AD/CE era. ... May 18 is the 138th day of the year (139th in leap years) in the Gregorian calendar. ... 2007 (MMVII) is the current year, a common year starting on Monday of the Gregorian calendar and the AD/CE era. ... May 22 is the 142nd day of the year (143rd in leap years) in the Gregorian calendar. ...

See also

• Java Platform, Standard Edition
• List of Java APIs
• Free Java implementations
• Standard library

Java Platform, Standard Edition or Java SE (formerly known up to version 5. ... This is a list of Application Programming Interfaces (APIs) for the Java Programming Language. ... 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. ... In C++, the Standard Library is a collection of classes and functions, which are written in the core language. ...

External links

• Java SE Main page
• Java SE 6 API Javadocs
• Java SE API documentation
• Java software development kits (status as of August 2006):
  • 1.7 (early development)
  • 1.6 (stable, current)
  • 1.5 (stable)
  • 1.4 (stable)
  • 1.3 (obsolete)