Welcome to Experts Exchange

Add your voice to the tech community where 5M+ people, just like you, are talking about what matters.

  • Help others & share knowledge
  • Earn cash & points
  • Learn & ask questions
Solved

interface and abstract class

Posted on 2011-09-07
5
413 Views
Last Modified: 2012-05-12
i would like to know about interface and abstract classes.
i read as
you need some classes to use some methods which you don't want to be included in the class, then you go for the interface, which makes it easy to just implement and make use of the methods defined in the interface.

abstract classes when
Abstract classes are an excellent way to create planned inheritance hierarchies. They're also a good choice for nonleaf classes in class hierarchies.

I am not clear on this this explanation. Thanks in advance
0
Comment
Question by:gudii9
  • 2
5 Comments
 
LVL 4

Accepted Solution

by:
SafetyFish earned 250 total points
ID: 36495735
This seems like a pretty simple explanation to me:

http://flylib.com/books/en/1.489.1.30/1/

This is short, but sweet and seems to include a nice example of simple code for abstract classes and members. Comparison to interfaces is only cursory:

http://www.startvbdotnet.com/oop/abstract.aspx

This also seems like it is a good article:

http://www.javaworld.com/javaworld/javaqa/2001-04/03-qa-0420-abstract.html

I really like the comparison table between the two on this website:

http://mindprod.com/jgloss/interfacevsabstract.html
0
 
LVL 1

Assisted Solution

by:amirms
amirms earned 250 total points
ID: 36501120
Interface is simply an abstract class which all of its methods are abstracts i.e. non of the methods have implementations. An abstract class in contrast can include implemented methods (i.e. methods which already contain functional work and are simply inheritted to the children classes) an Interface does not contain implemented methods i.e all the methods in there are just declared so that the children can implement them.

Basically, if the children of a parent class have no common implementation of methods which they inherit, we define their parent as an abstract. For example if parent class "Shape" has only one non-private abstract method called "Draw()" and its two children classes namely "Circle" and "Rectangle" do not have a same way of drawing themselves, we could simply define "shape" as an abstract class and leave "Circle" and "Rectangle" to draw themselves however they are required to by implementing the "shape" class.
0
 
LVL 59

Expert Comment

by:Kevin Cross
ID: 36935270
This question has been classified as abandoned and is closed as part of the Cleanup Program. See the recommendation for more details.
0
 
LVL 4

Expert Comment

by:SafetyFish
ID: 36912527
Sounds good to me.
0

Featured Post

Master Your Team's Linux and Cloud Stack!

The average business loses $13.5M per year to ineffective training (per 1,000 employees). Keep ahead of the competition and combine in-person quality with online cost and flexibility by training with Linux Academy.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Suggested Solutions

Title # Comments Views Activity
xampp tool 12 56
java jdbc batch example 8 39
Java string replace 11 53
junit as external jar or library 7 22
Java contains several comparison operators (e.g., <, <=, >, >=, ==, !=) that allow you to compare primitive values. However, these operators cannot be used to compare the contents of objects. Interface Comparable is used to allow objects of a cl…
Are you developing a Java application and want to create Excel Spreadsheets? You have come to the right place, this article will describe how you can create Excel Spreadsheets from a Java Application. For the purposes of this article, I will be u…
Viewers learn about the third conditional statement “else if” and use it in an example program. Then additional information about conditional statements is provided, covering the topic thoroughly. Viewers learn about the third conditional statement …
Viewers will learn one way to get user input in Java. Introduce the Scanner object: Declare the variable that stores the user input: An example prompting the user for input: Methods you need to invoke in order to properly get  user input:

790 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question