• RELEVANCY SCORE 5.88

    DB:5.88:What Is Difference Between Abstraction And Abstract Class ? j3




    What is difference between abstraction and abstract class ?

  • RELEVANCY SCORE 5.73

    DB:5.73:Difference Between Abstraction And Abstract 98




     Could anyone give diffference between abstract and abstraction with example..

    DB:5.73:Difference Between Abstraction And Abstract 98

     senthilkr wrote:

     
    Could anyone give diffference between abstract and abstraction with example..

  • RELEVANCY SCORE 4.24

    DB:4.24:Difference Between A Abstract Class With 4 Abstract Methods And A Interface With 4 Abstract Methods. 8c




    what is the difference between Difference between a Abstract class with 4 abstract methods and a Interface with 4 abstract methods.

    DB:4.24:Difference Between A Abstract Class With 4 Abstract Methods And A Interface With 4 Abstract Methods. 8c

    Your question is better rephrased as: What is the difference between an abstract class and a interfase?
    This has been discused here
    http://social.msdn.microsoft.com/Forums/en-US/csharpgeneral/thread/67451957-f0bd-4b9b-a2c0-16f604ce8643
    Regards

  • RELEVANCY SCORE 4.23

    DB:4.23:What Is The Difference Between Abstract And Concrete Wsdl? ap


    What is the difference between Abstract and concrete WSDL?

    DB:4.23:What Is The Difference Between Abstract And Concrete Wsdl? ap

    see : https://blogs.oracle.com/aia/entry/aia_11g_best_practices_for_dec
    for an example

    we use the abstract wsdl's so we're able to develop the process wether or not the environment (of the concrete endpoint) is up and running

  • RELEVANCY SCORE 4.22

    DB:4.22:Difference B/W Abstract &Amp; Interface dx


    Anyone tell me 4 difference b/w abstract class and interface
    plz help me

    DB:4.22:Difference B/W Abstract &Amp; Interface dx

    Asking once is enough.
    http://forum.java.sun.com/thread.jspa?threadID=734361

  • RELEVANCY SCORE 3.89

    DB:3.89:Abstract Class And Interface mc


    From the design perspective what is the difference between Abstract class and Interface.
    If we are providing design, for a system. When should we use abstract class? and when should we use interface.

    DB:3.89:Abstract Class And Interface mc

    And,
    you can only "extends" one abstract class;
    but "implements" several interfaces.

  • RELEVANCY SCORE 3.82

    DB:3.82:Re: Difference Between Abstract Class And Interface 7k


    See reply #44 and then please find something more useful to do.

    DB:3.82:Re: Difference Between Abstract Class And Interface 7k

    Passionate_Java_Lover_Vijay wrote:
    hi tigers,
    i am very new to java.
    i have a doublt iin collection.
    at wht situation what interface wil be best than other.

    where should i use List Set, Map and all.
    Advance thanks 2 guys who help me.

    Thanks
    ThinkGodJebus. Are you for real? Get a grip will you

  • RELEVANCY SCORE 3.78

    DB:3.78:Difference Between Interface And Abstract Interface 8a


    What is the difference between the following?

    interface Sample{

    }and

    abstract interface Sample{

    }Please explain it with an example.

    DB:3.78:Difference Between Interface And Abstract Interface 8a

    An all the interface's methods are public and abstract, even if you don't declare them as such. And all it's variables are public, static final, even if you don't declare them as such.

  • RELEVANCY SCORE 3.75

    DB:3.75:Interfaces Vs Abstract Classes 1d


    Hi All !!!
    Can any body please tell the difference between Interfaces and Abstract Classes in terms of Third Party Convince, Homogenous and HAS-A Relation Ship.
    Regards,

    DB:3.75:Interfaces Vs Abstract Classes 1d

    do your own homework. had you just asked for the differences, you would probably have gotten an answer, but you've just dumped your homework on the forum and said "do this for me" which we won't

    search the forums for this, it's asked almost every day. but those homework questions? that's your own problem

  • RELEVANCY SCORE 3.72

    DB:3.72:Main Difference Between Virtual And Abstract Method 19


    Hi All,
    Please explain themain difference between virtual and abstract.

    Thanks in advance.

    DB:3.72:Main Difference Between Virtual And Abstract Method 19

    1 more difference is...
    Abstract methods can reside in Abstract Class only. you cannot put abstract method inconcrete class.

  • RELEVANCY SCORE 3.70

    DB:3.70:Abstract Class And Interface???? ja


    hi all, i would like to know the difference between abstract class and interface....could anybody enlighten me on this....

    DB:3.70:Abstract Class And Interface???? ja

    search the forums, lot's of times answered this one has been.

  • RELEVANCY SCORE 3.70

    DB:3.70:Java Interfaces 1a


    Java allows to put 'abstract' keyword while declaring an interface, but by definition interfaces are support to be abstract, so whether there is any specific meaning of declaring an interface abstract. I mean whats the difference between an interface and an abstract interface?

    DB:3.70:Java Interfaces 1a

    No difference whatsoever. I believe the "abstarct" keyword in interfaces is an ingheritance from previous versions

  • RELEVANCY SCORE 3.70

    DB:3.70:Use Of An Abstract Keyword 37


    Hi all , I want to know about

    1.the usage of an abstract keyword.

    2.Difference between abstract and interface

    3.When to use abstract keyword.

    DB:3.70:Use Of An Abstract Keyword 37

    Hi all , I want to know about Give it a try yourself first, post it here and you get feedback.

  • RELEVANCY SCORE 3.66

    DB:3.66:Abstract Class Doubt ?? 7k


    what's the difference between the first abstract class and second abstract class .. when and where to use the first type and second type .. Please give me some info on it ...

    First Abstract Class
    public abstract class TestT where T : class
    {

    }

    Second Abstract Class

    public abstract class Test
    {

    }Regards, Gullu.

    DB:3.66:Abstract Class Doubt ?? 7k

    The second class is just a general abstract class - class that cannot be instantiated and is meant to provide common definition of a base class that multiple derived classes can share.
    More about abstract classes on MSDN.
    The first one is a generic abstract class that uses constraints to place requirements on the generic parameter (T). In your case the generic parameter can only be a type that match or inherit from specific base (you call this type 'class').
    e.g.

    public class Testable
    {

    public void Test()
    {
    //some logic here
    }

    }

    public abstract class TestT where T : Testable
    {
    public T t1;

    public void DoWork()
    {
    t1.Test(); //this will work because T must be of type Testable
    }
    }

    More about constraints on MSDN.

  • RELEVANCY SCORE 3.66

    DB:3.66:Situation That Describes Difference Between Usage Of Inetrface And Abstract Class x8


    Hi,
    Can anybody please tell me the best example or situation where we can chosse between interface and abstract class?Thanks, Smiley:)

    DB:3.66:Situation That Describes Difference Between Usage Of Inetrface And Abstract Class x8

    Hi Smiley3,
    I am marking this issue as Answered. If you have any new questions or concerns about this issue, please feel free to let me know.
    Thank you and have a nice day!Min Zhu [MSFT]
    MSDN Community Support | Feedback to us
    Get or Request Code Sample from Microsoft
    Please remember to mark the replies as answers if they help and unmark them if they provide no help.

  • RELEVANCY SCORE 3.66

    DB:3.66:Static Vs Abstract Classes 17


    Just wondering if anyone knows the difference between static classes and abstract classes.

    How do static methods, static variables work?

    Is there such a thing as an abstract method?

    Thanks

    DB:3.66:Static Vs Abstract Classes 17

    Ok i think its easier to understand if u see some examples:

    abstract class X{
    protected int value;
    public abstract void setValue(int pValue);
    }
    class Y extends X{
    public void setValue(int pValue) {
    this.value=pValue;
    }//each class, which extends x has to implement this method, or the class has to be //declared abstract too
    }
    class Z extends X{
    public void setValue(int pValue) {
    this.value=2*pValue;
    }
    }

    You can use this inheritance-tree as follows:

    public class try {
    public static void main(String[] args) {
    X try=new X() //NOT possible!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
    X try=new Y();
    try.setValue(10); //the value-field of try has the value 10
    try=new Z();
    try.setValue(10); //the value-field of try has the value 20
    }
    }

    The techinque i used above is called "dynamical linking" and is one of the advantages of an objectoriented language.

    The main difference of abstract and static is, that you can't instantiate an abstract class direct.

    A static class or a static method and variables has just one (and only one!!) represantation during runtime. And if you want to change the value of a static variable within a method this method has to be static too.

    Example:
    public class StaticTest {
    static int counter;
    public StaticTest() {
    counter++;
    }
    public static void print() {
    System.out.println(this.counter);
    }
    }
    public class TestClass {
    public static void main(String[] args) {
    StaticTest test;
    for (int i=0;i10;i++) {
    test=new StaticTest();
    }
    StaticTest.print(); //the output would be 10!!!!!!!!!!!!!!
    }

    }

    I hope this helps

  • RELEVANCY SCORE 3.66

    DB:3.66:What Is The Difference Between Abstract And Interface? zd


    Could some one explain what is the difference between abstract class and interface class.

    Lets say I'm creating class why would I choose abstract over interface?

    THanks.

    DB:3.66:What Is The Difference Between Abstract And Interface? zd

    The difference between abstract classes and interfaces is interfaces are defined methods only. In abstract class methods are derived.

  • RELEVANCY SCORE 3.60

    DB:3.60:Swing And Awt ax


    What is the difference between Swing and the Abstract Window Toolkit?

    DB:3.60:Swing And Awt ax

    Ok thank you. Sorry you double posting :).

  • RELEVANCY SCORE 3.57

    DB:3.57:Interface &Amp; Abstract Class d3


    1whats the basic difference between an interface and an abstract class?
    when should one be using an interface or an abstract class?

    2whats the difference between method overriding and method overlaoding?
    does both of them has any relation with the instance of te class implementing them?

    DB:3.57:Interface &Amp; Abstract Class d3

    http://www.google.com/search?q=java+interface+%22abstract+class%22

    http://www.google.com/search?q=java+method+overloading+overriding

  • RELEVANCY SCORE 3.57

    DB:3.57:Abstraction Vs Interfacing d7


    I'm pretty sure you guys are going to think that this must be the stupidest question....!!!

    Ok. This is it.

    I find it hard to differentiate between the concept of abstract classes and interfaces. In the end when either of them are implemented the functionality they provide is more or less the same. If that is the case why does java provide both interfaces and abstract classes when either one of them would do the job gracefully. I'm sorry if I'm mistaken I'm totally confused.

    Whoever it is that ends up clarifying my doubt......thanks in advance :)

    DB:3.57:Abstraction Vs Interfacing d7

    In an interface, all methods are abstract and public
    in an abstract class, some methods can be defined in the abstract class yet some can be blank abstract methods left to be defined by subclasses

    Interface just means EVERY method must be declared public and abstract
    Advantages to this = you can implement multiple interfaces

    You cant implement an abstract class, you can implement an interface however

  • RELEVANCY SCORE 3.57

    DB:3.57:What Are Real Roles And Abstract Roles In The Albpm 6.0? jc


    Hi All,

    what is the difference between the Real role and abstract role? Can we assign a Real role to Abstract role and vice versa?

    Edited by: user10436555 on Dec 17, 2009 2:55 AM

    DB:3.57:What Are Real Roles And Abstract Roles In The Albpm 6.0? jc

    As you are adding roles in Oracle BPM's development environment called Studio, you are adding abstract roles. Each process with Interactive activies can have one or more abstract roles. If you're using Studio for testing, abstract roles are the only thing you need to be aware of. The participants you create in Studio are assigned the roles you added in the processes. When you log into Studio's testing environment, the participant can only perform the Interactive activities in the abstract role(s) you assigned to them in Studio.

    If you're using Oracle BPM's production environment called Enterprise, real roles are mapped (matched) to the abstract roles when you deploy the processes in your project. These real roles are created inside of Enterprise's web based Process Administration application or are automatically created and mapped if you click "Smart publish" when deploying.

  • RELEVANCY SCORE 3.56

    DB:3.56:Difference Between Abstraction And Encapsulation With Examples In C# ?? 3j


    can anyone please tell me the basic difference between abstraction and encapsulation with example.
    I have done lot of searches on the internet but didn't get anything which would prove the difference .
    so,it would be helpful if anyone guide me through the basic difference on the subject (with codes as the example).

    DB:3.56:Difference Between Abstraction And Encapsulation With Examples In C# ?? 3j

    in addition to the above excellent reply:

    encapsulation helps you to bring together an object's properties functions but abstraction means to simply abstract or hide away complexity.by encapsulation you do achieve abstraction as well because you do end up implementing functions / behaviors of the object so you do end up achieving abstraction as well right?you can use classes, etc to achieve encapsulation. abstraction, well there are numerous ways (apart from using classes: interfaces, virtual, abstract, etc)
    eg of encapsulation:
    //bringing together object's properties methods / functionality together
    class SomeClass
    {
    //public properties
    //public methods
    }

    focused eg of abstraction:
    interface IMyContract
    {
    // interface members
    }

    hope this helps!

  • RELEVANCY SCORE 3.56

    DB:3.56:Difference B/W Abstract Class And Interface mf


    Hi,
    can anyone tell the difference between Abstract class and an Interface?

    Thanks in advance!

    DB:3.56:Difference B/W Abstract Class And Interface mf

    The majoor diiffernce is that Interface canot ber
    inherited while absract calss can be inherited
    one abract class can iheret other abstract class
    while Interface doesnot???

  • RELEVANCY SCORE 3.55

    DB:3.55:Difference Between Abstract Classes And Interfaces And When To Use Each a1


    Hi,
    I want to know the exact implementation differences between an abstract classes and Interfaces.
    When would we use each of them..
    Its seems that each does the same kind of functionality...but we need to just extend an abstract class in one and implement an Interface in another.

    Do let me know.

    Thanks,
    Ravi

    DB:3.55:Difference Between Abstract Classes And Interfaces And When To Use Each a1

    Hi,
    I want to know the exact implementation differences
    between an abstract classes and Interfaces.
    When would we use each of them..
    Its seems that each does the same kind of
    functionality...but we need to just extend an abstract
    class in one and implement an Interface in another.

    Do let me know.

    Thanks,
    RaviHi Ravi,
    A class must be declared abstract if one or more of its method is abstract. In case of an Interface, ALL the methods MUST be abstract. As java does not support multiple inheritence, Interface comes handy. In java, a class cannot extend from more than one class. To incorporate multiple inheritance, one can extend a class from another class and implement interface.

    public TestClass extends AbsClass implements Inter {
    }

    Thanks,
    Hope this helps,
    Karthick

  • RELEVANCY SCORE 3.52

    DB:3.52:Abstraction And Encapsulation p1


    Hi,

    Can I have the difference between Encapsulation and Abstraction with Jave Program Example ..

    Regards,
    Rani.

    DB:3.52:Abstraction And Encapsulation p1

    Encapsulation refers to wrapping i.e binding of data and the methods with in an object. this is achieved by specifying them as private in the definition of the classNot quite:

    class X {
    private Object o;

    // ...

    Object getO() {
    return o;
    }
    }Private attribute, almost no encapsulation.

    And you still haven't said what the difference is, you just have explained both.

  • RELEVANCY SCORE 3.50

    DB:3.50:What Is Difference Between Abstraction And Encapsulation ? zd


    Hi,

    I am trying to figure out the difference between abstraction and encapsulation but confused.
    Both are used for data hiding then what is the exact difference ?

    Thanks.

    DB:3.50:What Is Difference Between Abstraction And Encapsulation ? zd

    Encapsulation is the hidding the irrelevant dataNot really. If the data is truly irrelevant, then why is it being maintained by an object? Encapsulation is a core precept of OO. The general idea is [tell don't ask|http://pragprog.com/articles/tell-dont-ask].

    - Saish

  • RELEVANCY SCORE 3.45

    DB:3.45:Abstract And Interface fa


    Dear Sir/Madam,

    Please let me know the difference between Abstract class and Interface.

    DB:3.45:Abstract And Interface fa

    I disappeared as i was checking the forums in javaworld.com, but now i will keep this site as main.

  • RELEVANCY SCORE 3.44

    DB:3.44:Abstract Class Vs Interface sc


    can anyone pls help me in understanding difference between an interface and an abstract class which has no function with implementation

    which is better abstract cls or interface in term of speed, features..?
    Thanksbahushekh

    DB:3.44:Abstract Class Vs Interface sc

    To Mike Feng or any other moderator,
    Can you unmark
    as answer the previous post from myself please?
    Reason: It has no relevance to the original question, I was just replying to the post preceding it from RudeDog2
    which I also feel, does not really relate to the original question.
    I will leave it to Rudy to decide if He wants that post to be unmarked.

    Regards,

    John

    Click this link to see how to insert a picture into a forum post.

  • RELEVANCY SCORE 3.44

    DB:3.44:Regarding Abstract Interface sa


    Hello,What makes the difference between the Normal Interfaces and Abstract Interfaces. Is there any technical differences between these two interfaces.Thank you

    DB:3.44:Regarding Abstract Interface sa

    HIAbstract message interface donu2019t have a direction and arenu2019t implemented in an application system. We use them to define the process signature of an integration process.These are also called as hidden Interfaces.The Message interface is the highest level representation of XML meta data. It has two important attributes: mode (Synchronous or Asynchronous) and direction (inbound or outbound). For Business processes, Abstract interfaces are used; these have a mode, but no direction. oReferences fault message types for exception handlingoContext objects can be assigned.oWSDL representation available for exportoStarting point for Proxy generation (ABAP and Java).cheers

  • RELEVANCY SCORE 3.44

    DB:3.44:Abstract Class 71


    Hi,
    can u tell me the exact difference between abstract class and interface.under which situations we should use this.

    DB:3.44:Abstract Class 71

    AmitChalwade123456 wrote:
    Anumanick wrote:
    Hi,
    can u tell me the exact difference between abstract class and interface.under which situations we should use this.A class implementing an interface must implement all of the methods defined in the interfacepublic abstract class ImNotImplementingThat implements Runnable {

    // public void run() {} I was going to implement this, but I can't be bothered

    }while a class extending an abstract class need not implement any of the methods defined in the abstract class. public class WhyAreYouMoaningAboutRead extends java.io.InputStream {

    // I won't compile, because I'm not implementing the abstract void method 'read'

    }Additionally, a class extending an abstract class can implement an infinite number of it's own methods.Erm

    An abstract class can contain non-abstract methods which do not have to be overridden in the subclass.Indeed

  • RELEVANCY SCORE 3.44

    DB:3.44:Inter Face And Abstract Class c3


    hi
    can u please tell me the difference between interface and an abstract class? In which situations they will be usefull.
    thank u
    shyam

  • RELEVANCY SCORE 3.44

    DB:3.44:Abstract Inteface 87


    What is the difference between Abstract interface and interface ?
    if there is no difference,why ServletRequest ,etc are abstract interface.
    Thanks
    Selva

    DB:3.44:Abstract Inteface 87

    SelvaBalaji wrote:
    in the eclipse have opened the interface.and where did eclipse get it from? Remember that it doesn't really matter at all and so we should probably spend our time learning more useful stuff.

  • RELEVANCY SCORE 3.43

    DB:3.43:What Is The Difference Between Abstract And Interface? d8



    and pls tell me how to know tat

    wen to use static and instance

    DB:3.43:What Is The Difference Between Abstract And Interface? d8


    Abstract class can have single inheritance and Interface can have multiple inheritance.

    Class can have abstract method, which implementation not done itself and subclasses can do. it means class can partial abstract but not in case of interface.

    Kind Rgds

    Ravi Lanjewar

  • RELEVANCY SCORE 3.41

    DB:3.41:Difference Between Interface And Abstract Class a1


    Hi sirs,

    Give me the differences between interface and abstract class
    and when we go for interfaces and abstract class in developing an application

    DB:3.41:Difference Between Interface And Abstract Class a1

    An interface is a 100% abstract class, which means it doesn't contain any code, just method names and signatures. You use abstract classes when you want some code to be shared among the inheritors.

    The advantage with interface is that a class can implement as many interfaces as you like, while it can only extend one (abstract) class.

    So, you use interfaces when you need to extend other classes or doesn't want any code shared, and abstract classes when you don't want to extend other classes, and would like to share some code.

  • RELEVANCY SCORE 3.36

    DB:3.36:Abstract Class And Interfaces s7


    I'm learning java on my own right now, but I still don't understand interfaces and abstract methods.What's the difference between an abstract class and interfaces? Why are interfaces important? Why can you not just create your own methods?

    Thanks

    DB:3.36:Abstract Class And Interfaces s7

    This question is asked and answered very often in this forum. Do a search.

  • RELEVANCY SCORE 3.36

    DB:3.36:Difference Between Abstraction And Encapsulation sd


    i'm new to java i'm some what confused in understanding what is the exact difference the abstraction and encapsulation. can any body send me the difference by using a small example

    DB:3.36:Difference Between Abstraction And Encapsulation sd

    class Person {
    private final Date birthdate = ...;

    long calculateAge() {
    return System.currentTimeMillis() - birthdate.getTime();
    }
    }Simplified, this would rather be encapsulation.

  • RELEVANCY SCORE 3.36

    DB:3.36:Difference Between Abstract Interface And Normal Interface za


    Hello Friends,

    What is the Difference between abstract interface and normal interface?....

    DB:3.36:Difference Between Abstract Interface And Normal Interface za

    What is the Difference between abstract interface and
    normal interface?....The difference is that you didn't follow convention in the first case. All interfaces are implicitly abstract so you don't have to declare them as such.

  • RELEVANCY SCORE 3.36

    DB:3.36:Help Pls! 87


    Hi, can someone pls tell me what the difference between a normal class and an 'abstract class' is.

    Thanx!

    DB:3.36:Help Pls! 87

    Chris Evans just rang to call it off, apparentley he'd rather be seen with someone cool like Danny Baker and that my wife was too old for him.
    So I'll knock up a quick batch of proper nosh and meet yer all there. Hope you all like Pie and Mash Suchi, beautiful.

    Jamie

  • RELEVANCY SCORE 3.36

    DB:3.36:Diff Between Interface And Abstract Class 9a



    Hi to all,

    I am woking on OOP in ABAP .Could any one can tell the difference between interface and abstract class.

    thanks in advance .

    DB:3.36:Diff Between Interface And Abstract Class 9a


    Hello Sagar,

    like Uwe told one basic difference is that you may provide some methods with an abstract class but not with an interface. The unique feature of interfaces is that you may implement several ones while abstract classes are limited to one inheritance hierarchy.

    Regards

    Klaus

  • RELEVANCY SCORE 3.36

    DB:3.36:Java Interfaces And Abstract Classed fc


    what is the difference between interface and abstract class?

    DB:3.36:Java Interfaces And Abstract Classed fc

    I suggest you try writing some code and see.

  • RELEVANCY SCORE 3.36

    DB:3.36:Wsdl's sp


    Hi All,

    What is difference between abstract and concret WSDLS in SOA??

    Can anybody help to understand this?

    - Thanks

    DB:3.36:Wsdl's sp

    refer below links,

    _http://oraclesoaonline.blogspot.co.uk/2011/12/difference-between-concreate-wsdl-and.html
    _http://pushplsingh.blogspot.co.uk/2011/12/difference-between-concrete-and.html

  • RELEVANCY SCORE 3.35

    DB:3.35:Difference Between Abstract Class And An Interface 3z


    Hi,
    Can any one pls define that what is exactly difference between an Abstract Class and an Interface? Also I'll appreciate if some one can tell me that what we should prefer to use and why.
    Waiting for reply,
    Pranav

    DB:3.35:Difference Between Abstract Class And An Interface 3z

    Hm, it shows some uses but it (and it's predecessor article) actually don't tell what an abstract class or an interface is (or I overlooked it :-)

    Abstract class
    An abstract class is a class which can be declared and used to derive from, but which is not possible to instantiate.

    Like Animal - there is no animal, but there are Goldfish or Cat. Thus you want no Animal objects roaming your heap but only Goldfish and Cat instances. Still it makes sense to bundle the common features in Animal, and distribute them per inheritance.

    Interface
    While a class allows to group functions and variables into a unit, an interface only allows to group functions.
    Otherwise it is the same, thus can be derived from.

    However it makes no sense to create different instances of this, because you can't seperate them, there is no variable which would hold different state information that could be used for a comparison with nonequal result.

    Java offers the multiple inheritance from interfaces only, not from classes.
    This is a simplification chosen by the language designers to keep the implementation algorithms for the tools, the VM, the memory layout of the VM and perhaps the semantics complexity simple.
    (Java was intended for remote controls and other embedded devices).

    Why is this simpler?
    If A inherits from B and A inherits from C as well.
    Plus B inherits from D, plus C inherits from D,
    then we have no longer a tree/directed acyclic graph,
    but the more general case of a directed graph.

    This makes algorithms more complicated (tree walk is easier than graph walk, where you have keep track of cycles).

    Further instantiation make more trouble.
    An instance of A would contain two instances of D, one along the path A-B-D, and one along the path A-C-D.
    Thus if B,C,D were classes with variables, B-D's variables might be different from C-D's.
    This makes access semantics and storage much more complex.

    Java simplified this problem by avoiding it by just allowing interfaces for B, C, D.
    Calling A-B-D-f() is the same as calling A-C-D-f().

    Regards,
    Marc

  • RELEVANCY SCORE 3.35

    DB:3.35:Abstraction 7m


    Hi All,
    When I search for Abstraction- OOPS concept, I get results related to Abstract class and Abstract Method.
    Or the example for Abstraction includes abstract class or abstract method.
    Is abstract class isAbstraction?
    And in some search result, the Abstraction and Encapsulation is described with the change in Access modifiers.
    Which one is correct and if i want to describe Abstraction with Encapsulation which one should I use?
    Thanks,

    DB:3.35:Abstraction 7m

    Please also have a check on this thread:
    http://social.msdn.microsoft.com/Forums/en-US/csharpgeneral/thread/b54c98bf-e208-4332-b8f3-1dae944676ae/#5f733dbf-d483-4dcd-8d66-fbf6b2a5d1bf
    I've made a simple analogy to explain.Leo Liu [MSFT]
    MSDN Community Support | Feedback to us
    Get or Request Code Sample from Microsoft
    Please remember to mark the replies as answers if they help and unmark them if they provide no help.

  • RELEVANCY SCORE 3.30

    DB:3.30:Difference j9


    difference between abstract class and interface

    DB:3.30:Difference j9

    @OP You can see by the blatant obviousness and boring repetitiveness of these answers that this is a frequently asked question.

  • RELEVANCY SCORE 3.29

    DB:3.29:Difference 7x


    Hi sirs,
    Give me the main differences between abstract class and interface.Dont give me the links sir,

    when we go to use for the interface and for abstract class in developing an application

    DB:3.29:Difference 7x

    Another link:
    {color:#0000ff}http://forum.java.sun.com/thread.jspa?messageID=9961601{color}

    db

  • RELEVANCY SCORE 3.29

    DB:3.29:Entity Framework With Sql Azure *And* Table Storage cp


    Has anyone ever seen any kind of work, patterns, examples of a successful impementation of an abstraction layer between EF4 (or any other popular ORM) that can communicate back to (and switch between) SQL Azure and Azure Table Storage?

    I'd like to abstract away persistence from the ORM model.

    Thanks!Auto-scaling & monitoring service for Windows Azure applications at
    http://www.paraleap.com

    DB:3.29:Entity Framework With Sql Azure *And* Table Storage cp

    Hello,
    Have you looked at the examples on www.odata.org? Both SQL Azure and Azure Table Storage expose OData Services. It sounds like OData may be the way to go for what you would like to achieve?
    http://www.odata.org/blog/2010/3/18/got-sql-azure-then-you%27ve-got-odata--Kind of gives a simple example using OData and how to set it up for SQL Azure.
    Sincerely,
    Rob Beene, MSFT

  • RELEVANCY SCORE 3.28

    DB:3.28:Abstract Class &Amp; Interface 17


    What is the difference between Abstract Class and Interface Class? What I understood is both has to be defined in the subclass i.e methods. Apart from that Interface supports multiple inheritance whereas Abstract class doesn't. When both has to be defined in the subclass and interface supports multiple inheritance why we still need Abstract Class.

    Thanks in Advance,
    R.Ravindhran

    DB:3.28:Abstract Class &Amp; Interface 17

    A class can only extend one other class (Abstract or not) but it can implement any number of interfaces.

  • RELEVANCY SCORE 3.27

    DB:3.27:Abstract Class 13


    Difference between abstract class and interface
    use of abstract class

    DB:3.27:Abstract Class 13

    This question has been asked here about a billion times:

    http://search.java.sun.com/search/java/index.jsp?qt=interfacenh=10qp=st=11rf=0since=country=language=charset=variant=col=javaforums

  • RELEVANCY SCORE 3.27

    DB:3.27:Confusion Between Abstract And Interface a8


    Hi all,
    i'm new to java, can somebody help to explain on abstract and interface method. As i know that abstract or interface does not provide implementation in the superclass and interface class respectively. All the implementation are done in subclass.. why not we use the inheritances and abstract method to solve the problem instead of using the interface... i can't see the difference between the abstract and interface.. can somebody provide me a good example to understand the interface well..

    p/s: pls correct me if i wrong... ;)
    thanks

    DB:3.27:Confusion Between Abstract And Interface a8


    public class abstract Mainclass{
    abstract double area();
    abstract double meter();
    }

    public class Subclass1 extends Mainclass{
    double area(){
    return 5+1;
    }
    }

    public class Subclass2 extends Mainclass{
    double area(){
    return 8+10;
    }
    }Let's say you have
    public class abstract AreaClass {
    abstract double area();
    abstract double meter();
    }And then when you are working on your second iteration and you want to use Dimension class for this purpose for your new code but you want to leave the old code alone. If you have made AreaClass an abstract class, this is impossible.
    public class AreaDimension extends AreaClass, Dimension {
    }will not compile. However if you had defined AreaClass as and interface you can do this:
    public class AreaDimension extends Dimension implements AreaClass {
    double area() {
    return height * width;
    }
    }Then you can pass this to any method that accepts an AreaClass as a parameter and you can also pass it to any method that takes a Dimension.

  • RELEVANCY SCORE 3.26

    DB:3.26:Abstract Class Or Interface ? 11


    can any one tell me the difference between an abstract class an an interface. which is more useful ?

    DB:3.26:Abstract Class Or Interface ? 11

    You could also try searching this site for your question. It has been discussed in other threads as well (I posted a simialar (how do you spell that?) question).

  • RELEVANCY SCORE 3.26

    DB:3.26:Outbound And Abstract Sync Message Interface Difference zs



    Hi Experts,

    Is there any difference between the input and output messagetype for Outbound/Inbound Synch Message Interface and Abstract Sync Message Interface.

    Do we need to mention the same input and output messagetype for both outbound and Abstract or it should be otherway around?

    Regards

    Sara

    DB:3.26:Outbound And Abstract Sync Message Interface Difference zs


    ---Is there any difference between the input and output messagetype for Outbound/Inbound Synch Message Interface and Abstract Sync Message Interface.

    No there is not. U can select any message type irrespective of the type of message interface.

    ---Do we need to mention the same input and output messagetype for both outbound and Abstract or it should be otherway around?

    Yes. As per ur requirement u can specify the same.

    Regards,

    Prateek

  • RELEVANCY SCORE 3.26

    DB:3.26:Abstract Class And Interface Use 1k


    hi

    i am asking some stupied questions. plz can any one tell me

    1) what is interface and abstract class ? one example?
    2) when do u go for interface and when do u go for abstract class?
    3) what is exact difference between abstraction and encapsulation?

    thanks in advance

    DB:3.26:Abstract Class And Interface Use 1k

    Mahaboob wrote:
    hi

    i am asking some stupied questions.I agree.

    plz can any one tell meHere's a much better idea. You go do some basic research on these questions which have been asked 1,000,000,000 times previously and then tell us what you think. Then we can have a lively discussion about your ideas.

    'kay?

    And just to get you started in the right direction here's something you can review that will answer part of or all of your questions [_http://java.sun.com/docs/books/tutorial/java/index.html_|http://java.sun.com/docs/books/tutorial/java/index.html]

  • RELEVANCY SCORE 3.26

    DB:3.26:Differenece Between Abstraction And Encapsulation mj


    hi
    please define diference between abstraction and encapsulation in opps with C# and real life example
    thanks in advance

    DB:3.26:Differenece Between Abstraction And Encapsulation mj

    Hi nitinsharma1983,
    You can get a lot of information about those concepts when you google such as:

    difference between abstraction and encapsulation?
    abstraction Vs encapsulation
    What is the difference between abstraction and encapsulation?
    This response contains a reference to a third party World Wide Web site. Microsoft is providing this information as a convenience to you. Microsoft does not control
    these sites and has not tested any software or information found on these sites; therefore, Microsoft cannot make any representations regarding the quality, safety, or suitability of any software or information found there. There are inherent dangers in the
    use of any software found on the Internet, and Microsoft cautions you to make sure that you completely understand the risk before retrieving any software from the Internet.
    Helen Zhou [MSFT]
    MSDN Community Support | Feedback to us
    Get or Request Code Sample from Microsoft
    Please remember to mark the replies as answers if they help and unmark them if they provide no help.

  • RELEVANCY SCORE 3.25

    DB:3.25:Java Programming 33


    what is the difference between 'abstract' class and 'interface'

    DB:3.25:Java Programming 33

    Hey, get back in line. Don't jump the queue :)Well I guess I haven't qualified myself for this
    year's hunt. Maybe I could get a free-card because I
    was always on the Most Arrogant List a few years ago.Ok. I'll be nice. You'll get a free pass.

    Kaj

  • RELEVANCY SCORE 3.23

    DB:3.23:Abstract Classes And Interfaces kp


    I am kinda new to Java but have been studying frequently. I have a question that is probably very simple: What is the difference/advantage between an abstract Class and an Interface?

    DB:3.23:Abstract Classes And Interfaces kp

    Search the forum. Here's a topic that addresses it:
    http://forum.java.sun.com/thread.jsp?forum=31thread=273324

  • RELEVANCY SCORE 3.22

    DB:3.22:Difference Between Interface And Abstract Class mj


    hello friends give me the difference between interface and abstract class
    and link to find java material

    Thanx

  • RELEVANCY SCORE 3.22

    DB:3.22:Why Interface?Differnce Between Interface And Abstract Class d3


    why we go for interface? what is the difference between interface and abstract class?

    can anyone plz explain with clear picture.

    DB:3.22:Why Interface?Differnce Between Interface And Abstract Class d3

    Look at his profile. He's nothing but a homework dumper anyway. Someone to be ignored.

  • RELEVANCY SCORE 3.20

    DB:3.20:Whats The Difference Between Abstract Classes And Interfaces? sp


    What's de advantage ov Interfaces and vice versa the advantage of the Abstract Classes?
    Thanks

    DB:3.20:Whats The Difference Between Abstract Classes And Interfaces? sp

    1. Interface only contains Skeleton methods (no implementation at all). An interface does not have member variables.

    2. Interface does not have access modifiers.
    3. However interfaces help us in achieving multiple inheritances i.e. a class cannot inherit multiple classes (also abstract class) but it can inherit multiple interfaces.

    4. Abstract class contains Skeleton methods as well as default implementation (common functionality).

    5. Abstract class contains member variables and access modifier (default is private).

    6. Use abstract class if you need to modify base class because once base class is modified, we don’t need to change sub classes. But in case of interface, once interface is created and used, we cannot change base class. In this case we may need to add new
    interface to accommodate required change.
    7. Use abstract class if you have to implement common functionality for closely related objects (default method with provide this).

    8. Use interface if you have to implement common functionality for uncommon objects or disparate objects (in sub class implementation will provide this).

  • RELEVANCY SCORE 3.19

    DB:3.19:Difference Between Pure Abstract Class And Interface? 89


    hi,
    i just want to know the difference between pure abstract class(as same as interface- no implementation of methods) and interface

    Thanks,

    DB:3.19:Difference Between Pure Abstract Class And Interface? 89

    A very nice and detailed article on this code project link (posted by Magnus).

  • RELEVANCY SCORE 3.18

    DB:3.18:Concept Of Abstract Class &Amp; Interface fc


    Hi friends,

    My question is what is the main difference between Abstract class Interface?

  • RELEVANCY SCORE 3.18

    DB:3.18:What Is The Actual Difference Between Interfaces &Amp; Abstract Classes..? 73


    Hi Friends..!

    Please let me know what is the actual difference between Interfaces and Abstract Classes. All we can do in Abstract classes(ofcourse, except method definitions), is still possible to do in Interfaces. Then, why the concept of Abstract classes..?

    In which situation, we need Interfaces rather than Abstract classes and Vice-Versa..?

    Regards,
    k.suresh

  • RELEVANCY SCORE 3.18

    DB:3.18:Interfaces And Abstract Classes fk


    hi,

    Can anyone help me regarding the difference between interfaces and abstract classes. What is the advantage of interface over abstract classes and viceversa. Obout the possibities of multple inheritance I know. I found allmost all people are talking some external answers.
    Why an abstract class cant we do it with concrete class.
    regards,

    Jayaprasad Viswanathan

    DB:3.18:Interfaces And Abstract Classes fk

    Abstarct class can never be instantiated. Same as interfaces.

    Can be
    subclassed.Same as interfaces.

  • RELEVANCY SCORE 3.18

    DB:3.18:Difference Between Interface And Abstract Class 71


    I'm confused on what is the difference of implementing n abstract class and inheriting an interface?

    DB:3.18:Difference Between Interface And Abstract Class 71

    Hi,
    i want to add a few more differences --
    1.The variable defined inside an interface is public, static and final means it's basically a constant,But in case of abstract class you can hide the variable in the implementation class means you can change the value of the variable.

    One very important thing about the these two feature is when to use what?
    Ans:If a group of object is having some common property such that they are not going to be changed over a period then create an Abstract class out of that property.But if only some object is having a common property but not all then create an interface out of that property and implement all that property in Subclass.

    Thanks.

  • RELEVANCY SCORE 3.18

    DB:3.18:What Is The Difference Between Abstract Class And Interface ? dd


    Hi,

    Could u plz tell me the difference between Abstract class and Interface?

    Thanks in advance.

    Gopi

    DB:3.18:What Is The Difference Between Abstract Class And Interface ? dd

    Lots.

    An abstract class can contain some method implementations, or indeed all the method implementations. It may contain methods with all the various access modifiers. It cannot be instantiated. A class may inherit from only a single abstract class.

    An interface contains only public method stubs and constants. A class may implement multiple interfaces. An interface cannot (obviously) be instantiated.

    Abstract classes are particularly useful when you need to provide a semi-complete implementation for reuse. Interfaces are used more like types.

    Look at java.util.* for some good examples of the use of both.

  • RELEVANCY SCORE 3.18

    DB:3.18:Best Situation That Describe Difference Between Interface And Abstract c7


    Hi, Please tell me the best example or situation where we should choose interface or abstract class?

    DB:3.18:Best Situation That Describe Difference Between Interface And Abstract c7

    Smiley,
    It is the same as about apples and computers.
    An Interface is a contract, it describes what a class should contain to implement it (and can than be used to to get those members of a class whichfulfillthe contract) but an interface contains no actual implementation.
    An Abstract Class is a class itself which can be (only) inherited used as base for another class, the members and properties of a base class can be used likewise the inheriting class.
    Because of above can an Abstract Class implement an Interface, however an Interface cannot implement an Abstract class.

    Success
    Cor

  • RELEVANCY SCORE 3.18

    DB:3.18:Difference Between Interface And Abstract Class? x1


    Hi,

    Can u plz explain
    at what scenarios we use interface and abstract class.?

    Thanks,
    B.Maruthi

    DB:3.18:Difference Between Interface And Abstract Class? x1

    If you had read the FAQ at the top of the forum home
    page you wouldn'y have bothered to ask this
    question.Anyways heres the link

    Read the question number 13 in this link

    http://access1.sun.com/FAQSets/newtojavatechfaq.htmlnice

  • RELEVANCY SCORE 3.18

    DB:3.18:Re: Difference Between Abstract Class And Interface. f3


    Thanks, jverd. I have got it.

    George

  • RELEVANCY SCORE 3.18

    DB:3.18:Difference Between Interface And Abstract Class zm


    What is the differrence between an abstract class and an interace? and when would you use one over the other?

    DB:3.18:Difference Between Interface And Abstract Class zm

    What is the differrence between an abstract class and
    an interace? and when would you use one over the
    other?To (over-)summarise:
    An interface defines what you want to do, but doesn't tell you how to do any of it.
    An abstract class may define some of how to do it, but not necessarily all.

    RObin

  • RELEVANCY SCORE 3.17

    DB:3.17:Difference Between Interface And Abstract Class zk


    hai

    please tell me what is the difference between interface and abstract class?

    when i want use inteface? when i want use abstrct class?

    give me the simple example for that?......

    DB:3.17:Difference Between Interface And Abstract Class zk

    This thread is moved from "JavaServer Pages (JSP) and JSTL" to here.

  • RELEVANCY SCORE 3.16

    DB:3.16:What Is Difference Between Interface And Abstract? 3s


    Many time, I just confuse the purpose of interface and abstract.
    When should use interface or abstract in real world?
    Please give me the difference point alike point of both interface and abstract.

    Thank you.

    DB:3.16:What Is Difference Between Interface And Abstract? 3s

    Hi
    Take a look on this
    http://www.c-sharpcorner.com/UploadFile/yougerthen/104232008193919PM/1.aspx
    Reguards

    The complexity resides in the simplicity Follow me at: http://smartssolutions.blogspot.com

  • RELEVANCY SCORE 3.15

    DB:3.15:Re: Abstract Class &Amp; Interface xp


    i posted a part of a pdf file for understanding about abstract classes and interfaces. trust me read it thoroughly and once you are finished you will say Ah.. that is why we use interfaces and abstract methods. This will give you a brief description on java inheritance, polymorphism and abstraction and interfaces.

    Good Luck

    DB:3.15:Re: Abstract Class &Amp; Interface xp

    Hai Ram! It is the batameeze leading the the
    batameeze!You mean budding budtameezee? ;)Yes budding. As in fungus that reproduce by budding. :-)

  • RELEVANCY SCORE 3.14

    DB:3.14:Difference Between Inheritance And Abstract Class 9s


    difference between inheritance and abstract class

    DB:3.14:Difference Between Inheritance And Abstract Class 9s

    There was never an episode of Blackadder where he tried to con his aunt out of an abstract class

  • RELEVANCY SCORE 3.14

    DB:3.14:Abstract Class And Interface 18


    what is the difference between abstract class and interface

  • RELEVANCY SCORE 3.14

    DB:3.14:Difference B/W Factory Pattern Abstract Factory Pattern ? 88


    Hi friends,
    Can anyone tell me what is the difference between factory pattern and abstract factory pattern ? I know how to implement factory pattern...
    Thanks!!
    MCP

    DB:3.14:Difference B/W Factory Pattern Abstract Factory Pattern ? 88

    Factory pattern violates OCP while Abstract Factory doesnt
    I tried to think about 3 factories here:factories from simpledesignpatterns
    Please, share Your thoughts there
    Thanks,
    Efim

  • RELEVANCY SCORE 3.12

    DB:3.12:What Is The Difference Between Abstract Class And Interface jf


    Hi,
    Can you please tell me the differences between Abstract class and Interface.
    In which scenarios we have to use Abstract class and in which scenarios should use Interface.

    Thanks and Regards
    Kranthi

    DB:3.12:What Is The Difference Between Abstract Class And Interface jf

    http://stackoverflow.com/questions/761194/interface-vs-abstract-class-general-oo

  • RELEVANCY SCORE 3.10

    DB:3.10:C#: Data Abstraction And Abstract Data Types 3f


    Hi!
     
    I'd like to know what is 1. Data Abstraction (apart from abstract class) and 2. Abstract Data Types in C#? Example?
     
    Thanks

    DB:3.10:C#: Data Abstraction And Abstract Data Types 3f

    You can find textbook definition here among other places.
    Abstract types are types that describe how things are done and not necessary have the actual implementation to do them. In C# this is typically done using Interfaces where you define a contract that all types that implement this interface must adhere to. So something like IEquatable is an abstract data type, but I'm guessing that's not what you asked about.
    The other option is to have abstract classes in C#. Examples include System.Diagnostics.TraceListener which is an abstract class where there are many implementation of a TraceListener (in the framework and out) but they all have some common things that describes what a TraceListener is.
     

  • RELEVANCY SCORE 3.10

    DB:3.10:Interface And Abstract Class c8


    Hi,

    Could you please let me know what is the exact difference between interface and abstract class.Which one is better to use .Could you please give me indepth answer.

    DB:3.10:Interface And Abstract Class c8

    Stop. Stop. Stop. I beg you...You're behaving like a Chinese gentleman with sand in his boots. Stop.

    Do we save the execution time by using interface.This is a compiler/byte code related question. Please post it in the proper place.

    What might be the behaviour inside the memory
    location by using interface and abstract class.Same answer.

    /Morten

  • RELEVANCY SCORE 3.08

    DB:3.08:Abstract Vs Interfaces sx


    hi i am looking for the difference between abstract classes and interfaces. i have refered a couple of books but nothing seems to satisfy me. and another thing when to use an abstract class and when to use an interface( other than multiple inheritence)

    thanks

    DB:3.08:Abstract Vs Interfaces sx

    In my opinion, Java sun programmers construct
    abstract classes in order to prevent some of the
    disadvantages of interfaces such that using only
    empty bodied method.It is a joke do not take it serious but it is really true that they construct abstract classes in order to prevent some of the disadvantages of interfaces

  • RELEVANCY SCORE 3.08

    DB:3.08:Re: Java Abstraction Concept? fm


    JavaFunda wrote:
    then whats the difference between inheritance and abstraction?Abstraction is the separation of "what" from "how." For example, an interface is an abstraction which defines what a given type must do (for instance, a Collection must provide add(), contains(), iterator(), etc.methods) without worrying about how it does it. When I declare a variable as a List, all I care about are that it provides certain capabilities and behaviors. I don't care how it implements them.

    Inheritance defines an "IS-A" relationship, and is the mechanism by which a subtype has the same operations and attributes as its parent. It's what ensures that ArrayList can do everything that AbstractList, List, Collection, and Object can do.

    DB:3.08:Re: Java Abstraction Concept? fm

    JavaFunda wrote:
    then whats the difference between inheritance and abstraction?Lets assume you have a car. You want to drive it..now while you are going to drive...do you really want to know how the break works, or how the transmission system works?? surely not[if you are not totally a nerd and try to find out everything...]. You just know how to drive it.

    Like this when in java you are using a component...say Collection.retainAll(Collection?)..you just need those elements that are common to both collections..now you just pass the arguments and get the result..you do not bother to know the details of retainAll() method. Just like when you are driving a car and using a component..you are passing arguments..like increasing the accelerator,applying breaks...completely unaware of the actual logic. So the logic of the car is abstract to you..you dont know it..but you use it..same here in java.

    Now in inheritance..Lets say you have a son/daughter[just assume it..no offence]... He/She has all the qualities like you.. but he/she may redefine a property..say he/she may not work as you would..etc. So here your sibling has obtained the quality from you but has modified it...it same here in java.. Child classes can modify or use the same method from their parents.

  • RELEVANCY SCORE 3.08

    DB:3.08:Subclass Vs Concrete Class fs


    Hi,

    What is the exact difference between subclass and concrete class?

    What is the need in subclassing abstract class to again abstract class?

    Thanks in Advance,
    venu.

    DB:3.08:Subclass Vs Concrete Class fs

    Hi,

    U mean to say Concrete classes are instantiatable
    and every concrete class is a subclass of some
    super class.Plz clarify me if i am wrong.That's correct. But it's also true that every class--both concrete and abstract--is a subclass of some superclass, except Object which has no superclass.

    NOTE: The following is simply provided in the interest of completeness because I'm a ballsniffing pedant. It's not that important to what you're asking about, and may just cause more confusion. Feel free to ignore it.

    Also, it's possible to make a concrete class non-instantiable by having a single private constructor and throwing an exception from it, but that's a runtime issue--the compiler will let you insstantiate the class (only from within itself if the c'tor is private).

  • RELEVANCY SCORE 3.08

    DB:3.08:Difference Between Abstract Class And Interface 71


    Here is a fresher in Java. Could any body tell me the difference between Abstract Class and Interface. And suppose Abstract class has three methods, in those, two of them are Abstract and one is normal method, and it has been implemented in that class itself. If we extend the Abstract class to our class, do we need to over ride or implement all the methods that are there in the Abstract class or we need to implement only those methods that have been declared as abstract. If it is so, then what is the purpose of implementing non abstract method in the Abstract class.

    Sravan

    DB:3.08:Difference Between Abstract Class And Interface 71

    public abstract class TestAbstract {
    public abstract void method1();
    public abstract void method2();
    public static void method3() {
    // non-abstract method must have a body
    }
    }

    public class TestAbstract2 extends TestAbstract {
    public void method1() {
    // Does not work:
    // Object test = new TestAbstract();
    TestAbstract.method3();
    }
    public void method2() {
    }
    }- you will have to implement all method which are declared as abstract. you do not need to implement method3 in this example., only method1 and method2.
    - an abstract class cannot be instantiated (doesn't work: Object test=new MyAbstractClass())
    - a non-abstract method in an abstract class can be used, if it's a static member.
    - with "extends" you can only have one class, and your class will inherit the members of the superclass
    - with "implements" you can use multiple interfaces, which are only a description of what you have to write yourself...

  • RELEVANCY SCORE 3.08

    DB:3.08:Difference Between Abstract Classes Vs Interface 77


    Hi,
    Can u pls mention all the differences between Abstract Classes and Interface.? I've mentioned the differences I've known here.

    Known Differences:
    ------------------
    (*) An interface cannot implement any methods, whereas an abstract class can.
    (*) A class can implement many interfaces but can have only one superclass

    Can U pls mention at what situation(practical situation) we've to go for abstract class or Interface?
    Tell me the situation when we have to go for abstract class?
    Tell me the situation when we have to go for interface?

    Please Reply me
    Thanks Regards
    Venkatesh

  • RELEVANCY SCORE 3.08

    DB:3.08:Abstraction 3p


    if a class extends an abstract class does the subclass have to implement all abstract methods in the abstract class?
    e.g
    abstract class Shape
    {
    public abstract double area();
    public abstract double perimeter();
    }
    class Rec Extends Shape
    {
    }
    --- Does class Rec have to implement both area() and perimeter() methods or can it choose to implement area only? Please help

  • RELEVANCY SCORE 3.07

    DB:3.07:C#: What Is Difference Between Abstract Class And Interface? How To Decide To Use Which One? 18


    I have been asked a question: how to decide to use Abstract class or Interface?
    We know that the Interface is special Abstract. All definitationsare default public and without implemetion. Classed inherit from interface has to implement all definitions.

    Abstract class does not need to implement all the methods and it can not be instantiated.
    Classes inheritfrom abstract classmay sharecommon logic (properties or methods) with abstract class and also override some methods' behavior.
    How to clearily answer this question? Thx!

    JaneC

    DB:3.07:C#: What Is Difference Between Abstract Class And Interface? How To Decide To Use Which One? 18

    Hello JJChen,
    Interface class can be implement in small units of data but abstraction class can be implemented in large units of data.
    1. Here is explanation of
    Interface class
    2. Here is explained
    Abstraction class.
    3.
    Difference betweenAbstraction andInterface class.
    Hope it will help you a lot.
    thanks,

  • RELEVANCY SCORE 3.07

    DB:3.07:Does Abstraction (Oops Concept) Means Using Abstract Class.....People Are Really Confused About This m7


    Does abstraction means implementing or using Abstract class in C#.
    Ref: http://forums.asp.net/t/1258933.aspx/1
    In the above forum the people are giving different views..such as
    One guy says Abstraction : Abstraction means hiding the complex thing and showing essential thing(like TV or Car)
    Another guy says Abstraction :Abstraction means that you have some class that is more common than others that extend it.
    Which one of the above statement is true...
    If the first statement is true hiding the complex thing..please give us real example with completed code..
    else if the second statement is true please explain it with sample codeilikemicrosoft

  • RELEVANCY SCORE 3.04

    DB:3.04:Difference From Design Perspective 9f


    Hi,
    Can nybody tell me the difference between abstract class and interface from design point of view. This questions waz asked 2 me in an interview.

    Tx.

    Naseem Khan

    DB:3.04:Difference From Design Perspective 9f

    Well. if you really need to know the details check
    out page 118 of the Java Language Spec. The summary
    is:

    - more than one interface can be implemented by a
    class.
    - an abstract class can contain implementation.That is not the big difference, but one will see it if one contemplates on this a little.

  • RELEVANCY SCORE 3.04

    DB:3.04:Difference Between Inteerface And Abstract 11


    Hi,Please Anyone can tell me What is the difference between Abstract and Interface?Where we can use interface and where we can use abstract?What is the uses of both?

    DB:3.04:Difference Between Inteerface And Abstract 11

    I agree with the all of the above, just adding one more thing:
    An interface is a pure abstract

  • RELEVANCY SCORE 3.04

    DB:3.04:Difference Between Abstract Class And An Interface c3


    hi all,

    what is the difference between an ABSTRACT CLASS with full of METHOD DEFINITIONS and no implemented methods. AND an interface having the same definitions.

    In which situation we use abstract class and in which situation we use interface.

    what are the benefits.

    Can anybody explain it clearly.

    bye
    -hari

    DB:3.04:Difference Between Abstract Class And An Interface c3

    http://www.google.com/search?q=java+difference+abstract+interfaceTrying to teach a man to fish, are you?

  • RELEVANCY SCORE 3.04

    DB:3.04:Re: What Is The Difference Between An Interface And An Abstract Class? 1a


    8000 views already wow.

    DB:3.04:Re: What Is The Difference Between An Interface And An Abstract Class? 1a

    filestream wrote:
    As the two famous politicians, Jonathan Curry and Larry Craig are wont to say, "Glad I could serve you."

    Of course, each says it in entirely different situations but we're not here to discuss that. The members of the forums are happy just knowing that we've cleared 1 doubt.Now that you mention it, I take a wide stance in the interface/abstract class issue.

  • RELEVANCY SCORE 3.03

    DB:3.03:Help With Interface And Abstract cs


    Hi all

    what is the difference between an interface and an abstract class??

  • RELEVANCY SCORE 3.03

    DB:3.03:Regarding The Abstract And Interface km


    hai,
    I am new to java programming

    I want to difference between abstract interface,interface and abstract class

    public abstract interface Test{}

    public interface Test{}

    public abstract class Test{}

    which kind of situations use the above interfaces and abstract classes

    It would be helpfull if explain with example....

    Thanks

    DB:3.03:Regarding The Abstract And Interface km

    shashikumar, please don't multipost and don't use the browser's back button to edit your post. This creates multiple posts. I've removed the other thread you started a minute after this one.

    db

  • RELEVANCY SCORE 3.03

    DB:3.03:What Is The Difference Between An Abstract And An Interface Class? pk


    can anyone enlighten me on this, what is the difference between an interface and an abstract class? When should i use an interface instead of a class and vice-versa? thanks!

    DB:3.03:What Is The Difference Between An Abstract And An Interface Class? pk

    public class Test extends MyClass implements MyInterface {
    public Test() {
    someAbstractMethod();
    someInterface();
    someMethodInAbstractClass();
    super.someMethodInAbstractClass();
    }
    public static void main(String[] args) {
    Test foo = new Test();
    }
    public void someAbstractMethod() {
    System.out.println("someAbstractMethod() in Test");
    }
    public void someInterface() {
    System.out.println("someInterFace() in Test");
    }
    // public void someMethodInAbstractClass() {
    // System.out.println("someMethodInAbstractClass() in Test");
    // }
    }

    abstract class MyClass {
    public void someMethodInAbstractClass() {
    System.out.println("someMethodInAbstractClass() in MyClass");
    }
    public abstract void someAbstractMethod();
    }
    interface MyInterface {
    public void someInterface();
    }Run once, uncomment code, run again, compare output

  • RELEVANCY SCORE 3.03

    DB:3.03:Abstract/Virtual Events a3


    If you have an abstract base class which has an event that children may
    implement, and none of the base class methods connect or raise the
    event, then what's the difference between declaring that event as
    either abstract or virtual?  I can't find much of anything in the
    docs about abstract or virtual events.  

    DB:3.03:Abstract/Virtual Events a3

    IIRC (and bear with me, since I'm not near any docs), an event is effectively a field of type delegate, along with three hidden methods: raise, add and remove. Fields cannot be virtual, so one would assume that the virtual refers to the methods associated with the field.
    The base implementation of add, simply adds the delegate to the InvocationList of the delegate field, the remove reverses this operation, and the raise invokes the delegate.
    When you say MyEvent(this, EventArgs.Empty) for example, you are effectively calling the raise method. Now the interesting thing is that AFAIK you cannot override the add, remove raise methods. I can't remember why, but I'm fairly confident I'm right on this one. This sorta makes the virtual superfluous.
    If you want child classes to fire the event, the pattern is to provide a protected virtual OnEventName method which fires the method. This allows the child class to stop the event being fired if neccessary, and also to invoke it itself:
    class Parent {

    public event EventHandler MyEvent;
    protected virtual OnMyEvent() {

    if(MyEvent != null) {

    MyEvent(this, EventArgs.Empty);
    }
    }
    }
    class Child : Parent {

    public void MyMethod() {

    // Some code
    OnMyEvent(); // Fire MyEvent
    }
    // Optional, if you want to do stuff even if the event handler is not hooked up, or
    // want to modify when MyEvent is fired:
    protected void override OnMyEvent() {

    base.OnMyEvent(); // Fire MyEvent, if you want to.
    // Do some stuff.

    }

  • RELEVANCY SCORE 3.01

    DB:3.01:Difference Between Abstract Class And Interfaces 9a


    Hi,

    Any body can tell me In which scenarios we use abstract class and in which scenario we use interfaces.

    In real time applications.

    DB:3.01:Difference Between Abstract Class And Interfaces 9a

    [url http://www.javaworld.com/javaworld/jw-09-2001/jw-0921-interface.html] maximizing flexibility

  • RELEVANCY SCORE 3.01

    DB:3.01:Simple Query ac


    Difference between Abstract class and interface with practical example

    DB:3.01:Simple Query ac

    You are right; it was a simple query. (and I don't mean "simple" as in lacking complexity.)

  • RELEVANCY SCORE 3.01

    DB:3.01:Diff Between Abstract Class And Interface - Is This A Difference 7m


    This is quite a common topic thats discussed in any java forums . I would like to confirm if asked about the differences , can I say the following?.

    Abstract class can (or not ) have methods in it and it has no use in instantiating it since it has no meaning in instantiation.
    It has to be inherited for use .
    You need to INHERIT to use an abstract class.
    You can have a variable in Abstract class. ( a silly difference )
    Basically u use an abstract class when you want to provide a generalized form of abstraction and leave the implementation task with the inheriting subclass.

    Interface - group of related methods with empty bodies .
    You need to IMPLEMENT to use an interface.
    I dont think you can have a variable in a interface.
    When you want a few classes to use a few methods which you dont 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. But the problem with the interface is that, u have to implement all the methods defined in the interface , even if you dont need some of them.

    PLEASE LET ME KNOW IF THE VARIABLE THING IS A REAL DIFFERENCE. .
    I CANNOT HAVE A VARIABLE DECLARED IN MY INTERFACE RIGHT?

  • RELEVANCY SCORE 3.00

    DB:3.00:Abstract Classes mj


    why do we write abstract classes? why dont we write a concrete class instead?

    ex:

    abstract class A{
    abstract void shape();
    }

    why dont we write :

    class A{
    void shape(){
    }
    }
    and get this extended by some subclass?

    why do we need abstraction?

    DB:3.00:Abstract Classes mj

    you must re-learn object oriented programming :)

  • RELEVANCY SCORE 3.00

    DB:3.00:Why We Use Interface? c9


    I appeared one of my interviews.The Interviewee asked me a question that

    Suppose one is abstract class and one is interface.
    All the methods of abstract class are abstract.
    Then on this level what is the difference between abstract
    and interface and why we use interface. I could not answer properly.
    Please guide me the actual difference between Abstract class and Interface.
    Thanks

    DB:3.00:Why We Use Interface? c9

    google is your friend! Dear You are also my friend ;)

  • RELEVANCY SCORE 2.99

    DB:2.99:Abstract Classes And Interfaces? dp


    Can someone tell me whats the difference between abstract classes and interfaces?

    DB:2.99:Abstract Classes And Interfaces? dp

    ...alhough an abstract class doesn't have to have any abstract methods, or any methods at all for that matter. If it has an abstract method (or doesn't implement something from an interface it claims to implement) then it must be declared abstract, but the reverse is not true--any class may be declared abstract.

  • RELEVANCY SCORE 2.99

    DB:2.99:What Is The Difference Between Abstract And Normal Class k1


    What will be the difference if I replaced :
    public abstract MyWork {
    ....
    }
    [/code]

    by public MyWork { ........
    }

    THanks in Advance

    Tleis

    DB:2.99:What Is The Difference Between Abstract And Normal Class k1

    To clear all that up for those guys:

    An abstract class must be subclassed or instantiated as an anonymous class. It can have any of the same members as a regular class and in addition it can define abstract methods. Any abstract methods must be implemented by the subclass or else that class too must be declared abstract.

    An abstract class is different from an interface. Java gives you only a single ancester in your class hierarchy. You will force an implementation to become a descendant of your abstract class -- and therefore no other. In "object oriented programming", the term "an 'is-a' relationship" is used to describe that relationship between any subclass and its superclass. However you like to put it: this is the relationship you will be defining when you write your abstract class.

    - Steev.

  • RELEVANCY SCORE 2.99

    DB:2.99:Interfaces And Abstract Classes 8x


    Whats the difference between an interface and an abstract class.

    DB:2.99:Interfaces And Abstract Classes 8x

    Another trait that is often overlooked is that the abstract methods and constants declared in an interface are always public; with abstract classes, you can declare them (package) and protected scope as well.

  • RELEVANCY SCORE 2.99

    DB:2.99:Difference Between Abstract Class And Interface ? fz


    CAN ANY BODY TELL ME THE DIFFERENCE BETWEEN THE ABSTRACT CLASS AND INTERFACE ?

    DB:2.99:Difference Between Abstract Class And Interface ? fz

    - An abstract class is a class that can not be instantiated but that can contain code, i.e. it gives you the ability to specify default implementations of methods.

    - An interface only contains methods but does not contain any code and you need to implement all the methods defined in the interface.
    - Interfaces may be multiple-inherited, abstract classes may not
    http://www.codeproject.com/Articles/11155/Abstract-Class-versus-Interface
    http://stackoverflow.com/questions/56867/interface-vs-base-class