Please Post All Your Java Programing Questions Here.

If you really want to learn stuff about java, i suggest u lay your hands on books like: thinking in java, or java how to program,  They're available in pdf

Abstraction and Encapsulation are quite similar and confusing when you start oops programming, but heres my explanation:

Abstraction means hiding the internal details and just exposing the ‘relevant’ functionality (i.e. the interface). For Example:-When you change the gear of your car, you know the gears will be changed without knowing how they are functioning internally. Now I have not coded in Java for about a year  but from the top of my head:

public interface GearBox
{
   int gearOne();
   int gearTwo();
   int gearThree();
   int gearFour();
   int gearFive();
int reverse();
int neutral();
}

Encapsulation refers to the transparency of an object - information hiding. By hiding the information inside an object we prevent a client from making unauthorized modifications, why? it makes code more robust. For example:

public class NaijaCar extends Car implements GearBox
{
   public NaijaCar() {  //init code here }
   
   private double acceleration = 1.0;
      
   //Now implement the interface
   
public int gearOne()
{
   super.speed += acceleration;
}

public int gearTwo() {
   super.speed += acceleration * 2.0;
}
//And so on for gear 2,3 and 4
public int gearFive()
{
   super.speed += acceleration * 5.0;
}
public int reverse()
{
   super.speed -= acceleration;
}
public int neutral()
{
   super.speed = 0.0;
}
}

So you can see the Abstraction in the sense that users of NaijaCar use all mthe relevant gearbox methods without knowing the deatils of how each one works. some homework for you, where is the encapsulation in NaijaCar?

 

Abstraction is definitely an OOP basic.

Abstraction - from the word abstract - meaning overview - As an analogy, when you read a technical document. There's always an abstract which gives a general overview of what the document is about.

In Object Oriented programming, Abstraction gives the specification of an Interface. i.e it gives the Name of the interface and the names of all the methods in the interface but not the details. Any class that plans to implement that interface must use the specified methods. You make use of the specified methods but you supply the details in each method yourself.

Encapsulation on the other hand refers to the fact that the when a user uses an object of a class, he has no ability to change the inner operations of the class methods and variables. That is the internal operations of the class is shielded protected or encapsulated.

No where near as good as Visual Studio am afraid.

 ;d
public class NaijaCar extends Car implements GearBox
{
   public NaijaCar() {  //init code here }
   
   private double acceleration = 1.0;
      
   //Now implement the interface
   
public int gearOne()


The field decleared private cant not be accessed by anyone outside of the class

Helo people.plx can i get d rough estimate of being a sun java certified programmer/developer and how long it takes to run the programme,all tins being equal.tanx

Pls anyone with useful info to my questn shld pls email me-evagreenfields@gmail.com

Self study,@blacksta,i just want to read up java programming books and then sit 4 the programming exam,

 :'(hello moderator and all nairaland fan,i'm a graduate of mathematics/computer sci. After my graduation i decide 2 learn JAVA programming to boost my knowledge.but the language is difficult.i hav decide 2 pick it up,4rm 2moro.i need help my email is bluediva555@yahoo.com,pls if u hav any codes 2 assist me i'll be glad.

Familiarize yourself with the Java 2D API. It's a whole lot of package. You'll see lots of (hands-on) examples while learning!!!

Visit http://www.corewebprogramming.com/PDF/ch10.pdf for Java 2D tutorial.

Thinking in Java
By Bruce Eckel


* Publisher: Prentice Hall PTR
* Number Of Pages: 1098
* Publication Date: 1998-02-19
* ISBN-10 / ASIN: 0136597238
* ISBN-13 / EAN: 9780136597230
* Binding: Paperback



Product Description:

The legendary author Bruce Eckel brings Java to life with this extraordinarily insightful, opinionated and downright funny introduction. Thinking in Java introduces all of the language's fundamentals, one step at a time, using to-the-point code examples. More than virtually any other book, Thinking in Java helps you understand not just what to do -- but why. Eckel introduces all the basics of objects as Java uses them; then walks carefully through the fundamental concepts underlying all Java programming -- including program flow, initialization and cleanup, hiding implementations, reusing classes and polymorphism. Using extensive, to-the-point examples, he introduces error handling, exceptions, Java I/O, run-time type identification, and passing and returning objects. He covers the Java AWT, multithreading, network programming with Java -- even design patterns. The best way to understand the real value of this book is to hear what readers of the online version have been saying about it: "much better than any other Java book I've seen, by an order of magnitude, " "mature, consistent, intellectually honest, well-written and precise, " "a thoughtful, penetrating analytical tutorial which doesn't kowtow to the manufacturers, " "Thank you again for your awesome book. I was really floundering, but your book has brought me up to speed as quickly as I could read it!"For both beginner and experienced C and C++ programmers who want to learn Java.

* From the basics of object development, all the way to design patterns and other advanced topics.

* By the author of the best-selling Thinking in C++ -- winner of the 1995 Jolt Cola Award!

* On-line version has already received tens of thousands of hits -- there's a huge built-in demand for this book!

Download Links:
Code:

http://www.megaupload.com/?d=177J8HKO

Head First Java, 2nd Edition
By Kathy Sierra, Bert Bates


* Publisher: O'Reilly Media, Inc.
* Number Of Pages: 720
* Publication Date: 2005-02-09
* ISBN-10 / ASIN: 0596009208
* ISBN-13 / EAN: 9780596009205
* Binding: Paperback



Product Description:

Learning a complex new language is no easy task especially when it s an object-oriented computer programming language like Java. You might think the problem is your brain. It seems to have a mind of its own, a mind that doesn't always want to take in the dry, technical stuff you're forced to study.

The fact is your brain craves novelty. It's constantly searching, scanning, waiting for something unusual to happen. After all, that's the way it was built to help you stay alive. It takes all the routine, ordinary, dull stuff and filters it to the background so it won't interfere with your brain's real work--recording things that matter. How does your brain know what matters? It's like the creators of the Head First approach say, suppose you're out for a hike and a tiger jumps in front of you, what happens in your brain? Neurons fire. Emotions crank up. Chemicals surge.

Download Links:
Code:

http://www.megaupload.com/?d=RBKQ55WY

@blacksta, pls can i get a book for newbie programmers

head first  what of mouth first