Hey I m not able to understand the topics such as Abstract classes,annotations. Plz help me out.

And I also want to know how can i practice online java programs. I m not able to find some specific practice problems.:(

What don't you understand about those topics that Java Sun's articles can't answer? I'm not going to type you a paper about abstract classes and neither is anyone here, since the information is readily available. Ask a specific question.

I just want a simple small definition of abstract class or annotation if there is any.
Thats it.
Where can i practice programs?

You can get a simple definition from google.
And you can practice programs in a text editor, assuming you also have a compiler. Download eclipse if this is too much for you to handle.

Hi,

An annotation, in the Java computer programming language, is a special form of syntactic metadata that can be added to Java source code. Classes, methods, variables, parameters and packages may be annotated.

Java annotations can be reflective in that they can be embedded in class files generated by the compiler and may be retained by the Java VM to be made retrievable at run-time.

See the below example :


*********************************
// @Twizzle is an annotation to method toggle().
@Twizzle
public void toggle() {
}

// Declares the annotation Twizzle.
public @interface Twizzle {
}
*********************************

Hope this helps!
Let me know for more Confusions.. :confused:

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