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OAuth 2.0

OAuth 2.0 is an open authorization framework and mainly focuses on authorization flows fand secures access to many well-known web APIs.

Java 8 features

The key features of JDK 8 are Project Lambda (JSR 335), the Nashorn JavaScript Engine, a new Date and Time API (JSR 310), a set of Compact Profiles and the removal of the "permanent generation" from the HotSpot Java Virtual Machine (JVM). A complete list of the new features and capabilities of JDK 8 is available.

Lambda Expression

A lambda expression represents an anonymous function. It comprises of a set of parameters, a lambda operator (->) and a function body.


SOAP : Web service use XML messages that follow the Simple Object Access Protocol (SOAP) standard.
RESTful : Web service, often better integrated with HTTP than SOAP-based services are, do not require XML messages or WSDL service–API definitions.

Softwares Engineering / SDLC

Software engineers apply the principles of engineering to the design, development, maintenance, testing, and evaluation of the software and systems that make computers or anything containing software work.

Monday, September 13, 2010

Introduction to Java Language

Java is an object-oriented programming language with a built-in application programming interface (API) that can handle graphics and user interfaces and that can be used to create applications or applets. Because of its rich set of API's, similar to Macintosh and Windows, and its platform independence, Java can also be thought of as a platform in itself. Java also has standard libraries for doing mathematics.

Much of the syntax of Java is the same as C and C++. One major difference is that Java does not have pointers. However, the biggest difference is that you must write object oriented code in Java. Procedural pieces of code can only be embedded in objects. In the following we assume that the reader has some familiarity with a programming language. In particular, some familiarity with the syntax of C/C++ is useful.

In Java we distinguish between applications, which are programs that perform the same functions as those written in other programming languages, and applets, which are programs that can be embedded in a Web page and accessed over the Internet. Our initial focus will be on writing applications. When a program is compiled, a byte code is produced that can be read and executed by any platform that can run Java.

Download jdk1.6 from java.sun.com/javase/downloads/index.jsp. Double click on jdk1.6 and install java. Set path to c:\program files\java\jdk1.6\bin;

Java Directory Structure
Directory Structure
(The name may be different, for example, jdk5.0)
The compiler and tools
Look here for demos
Library documentation in HTML format (after expansion of j2sdkversion-doc.zip)
Files for compiling native methods (see Volume 2)
Java runtime environment files
Library files
The library source (after expanding src.zip)


James Gosling initiated the Java language project in June 1991 for use in one of his many set-top box projects. The language, initially called Oak after an oak tree that stood outside Gosling's office, also went by the name Green and ended up later renamed as Java, from a list of random words. Gosling aimed to implement a virtual machine and a language that had a familiar C/C++ style of notation. 

Sun released the first public implementation as Java 1.0 in 1995. It promised "Write Once, Run Anywhere" (WORA), 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. With the advent of Java 2 (released initially as J2SE 1.2 in December 1998), new versions had multiple configurations built for different types of platforms. For example, J2EE targeted enterprise applications and the greatly stripped-down version J2ME for mobile applications. J2SE designated the Standard Edition. 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 JTC1 standards body and later the Ecma International to formalize Java, but it soon withdrew from the process. Java remains a de facto standard, controlled through the Java Community Process. 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. Sun distinguishes between its Software Development Kit (SDK) and Runtime Environment (JRE) (a subset of the SDK); the primary distinction involves the JRE's lack of the compiler, utility programs, and header files.

On 13 November 2006, Sun released much of Java as free and open source software under the terms of the GNU General Public License (GPL). On 8 May 2007 Sun finished the process, making all of Java'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.