Introduction to Java, Jan Pettersen Nytun, page 1

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IntroductiontoJava
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History

• In 1991 Sun started development of a programming
  language that should be used for programming of
  consumer electronics, e.g. Mobile telephones,
  remote console, ...
• The language was originally named Oak by James
  Gosling, the creator of the language.
• The market was not ready for this language and
  the project goal was changed the language should
  be a language for the web.
• The browser HotJava was launched in 1995. The
  browser was written in Java and could execute
  applets (code running inside web-pages)
• Also in 1995 Netscape decided to make their
  web-browser Java enabled.

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More History

• The first versions of the language (e.g. Java
  1.02 released 1996) was not ready for industry
  use, they were to immature (e.g. when it comes to
  making user interface).
• In December 1996 a much more mature version was
  released Java 1.1. This version is much more
  mature (some browser has build in support for JDK
  1.1.6 and not later versions)

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Java 2 Platform
Micro Edition
Standard Edition
Enterprise Edition
Embedded devices(e.g. phones)
Network-centricapplications
Enterpriseapplications
KVM,
Applet, JavaBean
EJB, servlet, JSP
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The Java 2 Platform EditionsFrom
http//java.sun.com/docs/glossary.html

• Java 2 Platform, Standard Edition (J2SE platform)
  
• The core Java technology platform.
• Java 2 Platform, Enterprise Edition (J2EE
  platform)
• An environment for developing and deploying
  enterprise applications. The J2EE platform
  consists of a set of services, application
  programming interfaces (APIs), and protocols that
  provide the functionality for developing
  multi-tiered, Web-based applications.
• Java 2 SDK, Enterprise Edition
• Sun's implementation of the J2EE platform. This
  implementation provides an operational definition
  of the J2EE platform.

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JDK Java Devlopment KitFrom
http//java.sun.com/docs/glossary.html

• Java Development Kit software. A software
  development environment for writing applets and
  application in the Java programming language.

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Java And Javascript Should Not Be Confused

• From http//java.sun.com/docs/glossary.html
• JavaScript(TM)
• A Web scripting language that is used in both
  browsers and Web servers. Like all scripting
  languages, it is used primarily to tie other
  components together or to accept user input.

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Java is a rich language

• Java have packages for almost every thing.E.g.
• Web/Network (distributed applications)
• Multimedia
• Thread programming
• Graphics (GUI, 2D, 3D, ...)

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Making Portable Software

• A Java source code file contains code written in
  the Java language the source code is compiled to
  bytecode.
• The bytecode is stored in a class file. The
  bytecode is machine-independent and can be
  executed by a virtual machine.
• You have a virtual machine on most operating
  system platform, making your code portable
  portable across multiple machine architectures,
  operating systems, and graphical user interfaces.

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Java and Internet

• Applet
• A Java component that can be placed in a
  web-page and executed by a virtual machine inside
  a Web browser. It is also possible to execute an
  applet in a variety of other applications or
  devices that support the applet programming
  model.
• There are a lot of support for network
  programming
• Sockets
• Servlets
• JDBC for databaser
• ....

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Java and C

• Java is more object-oriented
• Java has automatic garbage collection and a well
  designed exception handling
• Java is a C dialect and easy to learn if you
  can C
• Java is less complex than C Java does not
  have
• Global variables
• Pointers
• Union
• Macroer/Preprocessor directive