What is datatypes in C.(Brief)

Data Types

Data types are provided to store various types of data that is processed in real life. A data type can be
described as a type of data or a data storage that can contain a specific type or range of values.

What is Eclipse?

Eclipse is a platform that has been designed from the ground up for building integrated web and application
development tooling. By design, the platform does not provide a great deal of end user functionality by itself. The value of the platform is what it encourages: rapid development of integrated features based on a plug-in model.
Eclipse provides a common user interface (UI) model for working with tools.  It is designed to run on multiple operating systems while providing robust integration with each underlying OS.  Plug-ins can program to the Eclipse portable APIs and run unchanged on any of the supported operating systems.
At the core of Eclipse is an architecture for dynamic discovery, loading, and running of plug-ins. The platform handles the logistics of finding and running the right code. The platform UI provides a standard user navigation model.  Each plug-in can then focus on doing a small number of tasks well. What kinds of tasks? Defining, testing, animating, publishing, compiling, debugging, diagramming...the only limit is your imagination.

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How to use the Eclipse IDE for the first time.

In this tutorial I will show you how to use the Eclipse IDE for the first time.
  
Once its downloaded & installed, double click the Eclipse icon to start.



Because this is your first time running Eclipse, it will take a while to load as it sets up the environment.




Once Eclipse is fully loaded you will see the Welcome Screen. You can close this straight away..



OK now lets start our first application.

Click File > New > Java Project



The 'Create a Java Project' box will popup.

Give your Project a name. In this case I have named it 'EclipseTutorial'



Click FINISH.

You have now setup your first project which will appear in the Package Explorer window.



Before we can begin to write any code, we must first add a Package which will contain all our project files.

Make sure your new project is highlighted and click the 'New Java Package' icon.



Give your package a name relevant to your project.



Click FINISH

Now your Package has been created we need to add a Class file. Make sure the Package is highlighted by clicking it once and then click the 'New Java Class' icon.



The Create a New Java Class box will popup.

Give your Class a name and tick the public static void main(String[] args) box.



Your Class will now appear in the Workspace and you are ready to start writing code!



Here I have wrote a simple Hello World application which will print the words into the console.



To Run your Java project. Right click the 'TutorialClass.java' file in the Package Explorer window, then click Run As > Java Application



The output will now be displayed in the console.



Congratulations! You have just wrote your first Java application in Eclipse!!

What is Java technology and why do I need it?

Java is a programming language and computing platform first released by Sun Microsystems in 1995. It is the underlying technology that powers state-of-the-art programs including utilities, games, and business
applications. Java runs on more than 850 million personal computers worldwide, and on billions of devices worldwide, including mobile and TV devices.

Why do I need Java?

There are lots of applications and websites that won't work unless you have Java installed, and more are created every day. Java is fast, secure, and reliable. From laptops to datacenters, game consoles to scientific supercomputers, cell phones to the Internet, Java is everywhere!

Is Java free to download?

Yes, Java is free to download. Get the latest version at http://java.com.
If you are building an embedded or consumer device and would like to include Java, please contact Oracle for more information on including Java in your device.

Why should I upgrade to the latest Java version?

The latest Java version contains important enhancements to improve performance, stability and security of the Java applications that run on your machine. Installing this free update will ensure that your Java applications continue to run safely and efficiently.

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MORE TECHNICAL INFORMATION

Originally called OAK, it was renamed as the Java programming language in 1995.

What will I get when I download Java software?

The Java Runtime Environment (JRE) is what you get when you download Java software. The JRE consists of the Java Virtual Machine (JVM), Java platform core classes, and supporting Java platform libraries. The JRE is the runtime portion of Java software, which is all you need to run it in your Web browser. When you download Java software, you only get what you need - no spyware, and no viruses.

What is Java Plug-in software?

The Java Plug-in software is a component of the Java Runtime Environment (JRE). The JRE allows applets written in the Java programming language to run inside various browsers. The Java Plug-in software is not a standalone program and cannot be installed separately.

I've heard the terms Java Virtual Machine and JVM. Is this Java software?

The Java Virtual Machine is only one aspect of Java software that is involved in web interaction. The Java Virtual Machine is built right into your Java software download, and helps run Java applications.

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Running a Java Program from Command Prompt

• Create a temporary folder C:\mywork.  Using Notepad or another text editor, create a small Java file HelloWorld.java with the following text:

  public class HelloWorld
  {
    public static void main(String[] args)
    {
      System.out.println("Hello, World!");
    }
  }

  Save your file as HelloWorld.java in C:\mywork.  To make sure your file name is HeloWorld.java, (not HelloWorld.java.txt), first choose "Save as file type:" All files, then type in the file name HelloWorld.java.
• Run Command Prompt (found under All Programs/Accessories in the Start menu).  Type

  C:\> cd \mywork

  This makes C:\mywork the current directory.

  C:\mywork> dir

  This displays the directory contents.  You should see HelloWorld.java among the files.

  C:\mywork> set path=%path%;C:\Program Files\Java\jdk1.5.0_09\bin

  This tells the system where to find JDK programs.

  C:\mywork> javac HelloWorld.java

  This runs javac.exe, the compiler.  You should see nothing but the next system prompt...

  C:\mywork> dir

  javac has created the HelloWorld.class file.  You should see HelloWorld.javaand HelloWorld.class among the files.

  C:\mywork> java HelloWorld

  This runs the Java interpreter.  You should see the program output:

  Hello, World!

  If the system cannot find javac, check the set path command.  If javac runs but you get errors, check your Java text.  If the program compiles but you get an exception, check the spelling and capitalization in the file name and the class name and the java HelloWorld command.  Java is case-sensitive!
• It is possible to make the path setting permanent but you have to be very careful because your system might crash if you make a mistake. Proceed with extreme caution! In Windows XP, go to Control Panel, choose "System," click on the "Advanced" tab, click on the "Environment variables" button. In the lower list, "System variables," click on Path:
  
  
  
  Click "Edit" and at the end append
  

  ;C:\Program Files\Java\jdk1.5.0_09\bin

  (or the path to the appropriate folder where the latest version of JDK is installed).  Do not put spaces before the appended path string.
   
  Click OK on the path edit box and OK on the Ennvironment Variables box.  The new setting will go into effect next time you run Command Prompt.
  
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