• RELEVANCY SCORE 5.75

    DB:5.75:What Is The Difference Between Abstract And Concrete Wsdl? ap




    What is the difference between Abstract and concrete WSDL?

    DB:5.75: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 4.88

    DB:4.88: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:4.88: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 4.52

    DB:4.52: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:4.52: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 4.32

    DB:4.32:Difference Between Concrete And Materialized View 19


    Hello everybody,
    As you can see above in the title, I'd like to know what is the real difference between concrete and materialized view.
    Thanks.

    DB:4.32:Difference Between Concrete And Materialized View 19


    I'd like to know what is the real difference between concrete and materialized view.

    See the detailed explanation in the Database Concepts doc
    http://docs.oracle.com/cd/B28359_01/server.111/b28318/schema.htm

    See 'Overview of Views' and 'Overview of Materialized Views'.

    A view is basically a stored query. There is no data associated with it. When you query the view Oracle executes the underlying query to obtain a result set.

    A materialized view is an actual table that contains data. The underlying query can be used to refresh the data so that the table contains a 'snapshot' of data as of the last refresh time.

  • RELEVANCY SCORE 4.28

    DB:4.28: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:4.28: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 3.90

    DB:3.90:Main Difference Between Virtual And Abstract Method 19


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

    Thanks in advance.

    DB:3.90: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 3.79

    DB:3.79:Abstract And Interface fa


    Dear Sir/Madam,

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

    DB:3.79: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 3.76

    DB:3.76:Abstract Classes And Interfaces? dp


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

    DB:3.76: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 3.76

    DB:3.76: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:3.76: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 3.75

    DB:3.75:What Is The Difference Between A Factory Class And A Concrete Class? f7


    Can someone help me, I am a new user for JAVA!!
    Thank you so much!!

    What is the difference between a FACTORY class and a CONCRETE class?
    And what purposes do they serve??

    DB:3.75:What Is The Difference Between A Factory Class And A Concrete Class? f7

    Also, note that factory-ness and concreteness are independent of each other. That is, all four permutationss of factory/not-factory, concrete/abstract are possible.

  • RELEVANCY SCORE 3.69

    DB:3.69: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:3.69: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 3.68

    DB:3.68: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:3.68:Difference Between Interface And Abstract Class zk

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

  • RELEVANCY SCORE 3.68

    DB:3.68:Re: What Is The Difference Between An Interface And An Abstract Class? 1a


    8000 views already wow.

    DB:3.68: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 3.67

    DB:3.67:C#.Net Difference Between Abstract Class And Sealed Class df


    Hi Experts, What is Difference Between Abstract Class And Sealed Class in C#? Thanks.

    Knowledge Shared Is Knowledge Gained

    DB:3.67:C#.Net Difference Between Abstract Class And Sealed Class df

    Hi Geert van Horrik, Thanks.Knowledge Shared Is Knowledge Gained

  • RELEVANCY SCORE 3.67

    DB:3.67:Need Help With Abstract Method ? 7p


    **************************************************
    public abstract void sleep()
    {
    ..........
    }
    **************************************************
    Could someone please tell me what is the difference of an abstract method in comparing to an instance or a class method? How should I do the invocation to an abstract method by other methods of its own class and of another class? Must I define abstract methods within abstract classes? Do I need to redefine abstract methods before using them? Thanx!

  • RELEVANCY SCORE 3.65

    DB:3.65: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:3.65: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 3.60

    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 3.54

    DB:3.54:Mapping Between Root Classes Of Two Tpct - Mapped Entities. fs


    Hello,I have 2 distinct trees of table - per - concrete - type mapped objects:1. Abstract Customer - not mapped to tables, East customer - mapped to tableCustomerEast , West customer - mapped to tableCustomerWest2. Abstract Order - not mapped, East order - mapped to tableOrderEast, West order - mapped to tableOrderWestCan I have an association between abstract customer and abstract order, and what would the mapping look like in this case?Thanks!

    DB:3.54:Mapping Between Root Classes Of Two Tpct - Mapped Entities. fs

    On a related note, if I use Multiple Entity Sets per Type strategy for both Customers and Orders (refer to http://msdn.microsoft.com/en-us/library/bb738537.aspx), is it possible to have an association between Customer and Order?

  • RELEVANCY SCORE 3.54

    DB:3.54:Simple Query ac


    Difference between Abstract class and interface with practical example

    DB:3.54:Simple Query ac

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

  • RELEVANCY SCORE 3.51

    DB:3.51: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:3.51: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 3.48

    DB:3.48:Super And This ff


    If I have an abstract class which contains a variable, say;

    protected int myInt ;

    what is the difference between calling super.myInt and this.myInt in the sub class ?

    DB:3.48:Super And This ff

    Depends. If you don't have a variable in the subclass with the same name, then it's just poor style. If you do, then they'll refer to different variables.

    Dave.

  • RELEVANCY SCORE 3.48

    DB:3.48: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 3.46

    DB:3.46:Interface And Abstract Class dd


    what is the difference between interface and Abstract class?
    What are the situations we have to go for interface and Abstract class?

    DB:3.46:Interface And Abstract Class dd

    Neither an abstract class nor an interface can be instantiated (meaning you cannot create the object directly with the "new" keyword). They are both similar in that they have abstract methods. (Technically, you can create an abstract class with no abstract methods, but I would question the utility of making that class abstract in the first place).

    The two main differences are the following:

    Implementation: An abstract class can implement methods, since it is a class. An interface can never implement any methods, it only declares their signatures.Inheritance: A given class can implement an unlimited number of interfaces. A class can only extend one class. In general, I use the following rules of thumb when deciding (other developers may have differing opinions):

    Given the choice, use an interface. Since you can implement an unlimited number of interfaces, they are not as restricted, from a class hierarchy perspective. If you have several classes with the same instance (class) variables declared and several methods that all accomlplish the same thing (normally, they will even have segments of code copy-pasted between classes), then re-factor the common variables and code into an abstract class. When using interfaces, always consider delegation. Delegation is something like the following:interface IFoo {
    abstract public void bar();
    }

    public class FooDelegate {
    final public void bar() {
    // Default implementation goes here
    }
    }

    public class FooImpl implements IFoo {

    final public void bar() {
    new FooDelegate().bar();
    }
    }

    The advantage of delegation is that you can write a "helper" that contains the implementation, and then the classes that actually implement the interface can simply use the helper (e.g., delegate the implementation to another class).

    - Saish

    "My karma ran over your dogma." - Anon

  • RELEVANCY SCORE 3.46

    DB:3.46:500m Ptp Link - Concrete Building Obstruction In Between ? 99


    hellocan i do a P2P Link between 2 points if there is a concrete Building between them? the distance between the 2 points is 500 M.Link is for VoIP and light internet browsing. what do you recommend?

    DB:3.46:500m Ptp Link - Concrete Building Obstruction In Between ? 99

    It is easy to do.wiki.ubnt.com/BeanstalkSee the article titled, Point to Point Indirect (Repeated) Link...Is this helpful?Cheers,GeneNice drawings Great work will be reading it over. I knew it was possible with a relay like you have done on the concrete building just thought it was not in the question?



    INTERNATIONAL Wi-Fi Hotspot Provider www.maiwifi.comUsing only the best firmware ~ airOS with our hotspot tabDOWNLOAD FREE Firmware install on any airMAX radio

  • RELEVANCY SCORE 3.46

    DB:3.46: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:3.46: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 3.45

    DB:3.45:What Is Difference Between Abstraction And Abstract Class ? j3


    What is difference between abstraction and abstract class ?

  • RELEVANCY SCORE 3.45

    DB:3.45: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:3.45: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 3.40

    DB:3.40:Good Simple Example Of Difference Between Interface And Abstract Class 83


    Hi All,

    I am new to java...

    I am confused lot about the difference between interface and abstract class....

    Can anybody tell me the difference between interface and abstract class with some good and simple exmple...

    Kindly help me...

    Thanks in advance...

    DB:3.40:Good Simple Example Of Difference Between Interface And Abstract Class 83

    phdk wrote:
    georgemc wrote:
    public class AbstractClassThatIsntAnInterface {

    public abstract void doSomething();
    public abstract void doSomethingElse();

    }Nice naming for a nonabstract class! ;-)

    @OP: read this: [http://java.sun.com/docs/books/tutorial/java/IandI/abstract.html]Er, you, um, spotted my deliberate mistake.....

  • RELEVANCY SCORE 3.36

    DB:3.36: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:3.36: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 3.35

    DB:3.35: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:3.35: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 3.34

    DB:3.34:Diference Between Abstract Class And Interface cp



     
    Hi,
     
    I had a doubt on basic concept of interface and abstract class.
     
    I had idea of wht is interface and abstract class but there is case ,can any do justification on these case is
     
    Abstract class is a clas where some methods r defined and some are abstract methods.
    Interface is where all methods are abstract .
     
    but what happen if i try to maintaince all methods in abstract class as abstract which is equivalent to interface.?
     
    We go for abstract class if want to extend functionality of class.For interface if we wanna implement a new implementation.
     
    is there any other difference apart from this and other issues if we try to have all methods abstract .
     
     
    With regards
    Mahender

    DB:3.34:Diference Between Abstract Class And Interface cp

    Hi,
     
    Thnx for giving info.Actually iam looking for projct development point of view..In whihc cases i do go 4 developing abstract classes  other interfaces

  • RELEVANCY SCORE 3.34

    DB:3.34:Looking For Help On Abstract Method f1


    how to use an abstract method? what is the difference between abstract and inheritance?

    DB:3.34:Looking For Help On Abstract Method f1

    An abstract method is a method that has not been implemented -- only its name, arguments, and return type have been given. This is useful from a design-by-contract viewpoint.

    You use them by overriding them, providing an implementation. (Or by not overriding them, and letting your class be abstract as a result.)

    They're so different from inheritance that it's not really meaningful to discuss the differences. It's like asking what's the difference between abstract methods and a bowl of onion soup. But they're related in that if you subclass a class with an abstract method, then your subclass has inherited the type information (i.e., the contract, the requirement to provide something that implements that method).

  • RELEVANCY SCORE 3.34

    DB:3.34: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:3.34:Abstract Class And Interface???? ja

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

  • RELEVANCY SCORE 3.31

    DB:3.31: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:3.31: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 3.30

    DB:3.30:Difference Between Abstract Class And Interface ? fz


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

    DB:3.30: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

  • RELEVANCY SCORE 3.30

    DB:3.30:Difference Between Abstract Interface And Normal Interface za


    Hello Friends,

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

    DB:3.30: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 3.27

    DB:3.27:Asb-Csb? 8f



    Hi all

    I'm new to sdk. I want to know wat is "abstract selection boss" "concrete selection boss". And wat is difference between them?

    thanks in advance

    THAMIL

  • RELEVANCY SCORE 3.27

    DB:3.27: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:3.27: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 3.26

    DB:3.26:Difference B/W Abstract Class And Interface mf


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

    Thanks in advance!

    DB:3.26: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 3.26

    DB:3.26:Java Programming 33


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

    DB:3.26: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 3.24

    DB:3.24: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 3.24

    DB:3.24: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:3.24:Difference Between Pure Abstract Class And Interface? 89

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

  • RELEVANCY SCORE 3.24

    DB:3.24:Concept Of Abstract Class &Amp; Interface fc


    Hi friends,

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

  • RELEVANCY SCORE 3.24

    DB:3.24:Abstract Interface ss


    Hi All,
    What is abstract interface?What is the difference between Abstract interface and interface?
    If there is no difference why ServletRequest is abstract inteface.
    Thank You,
    Selvaraj

    DB:3.24:Abstract Interface ss

    Have a look at the JLS Chapter 9.1.1.1 abstract Interfaces
    Every interface is implicitly abstract. This modifier is obsolete and should not be used in new programs

  • RELEVANCY SCORE 3.24

    DB:3.24:Diff Interface And Abstract Class af


    I would like to know difference between Interface and abstract class.

    I know simple differences ... like with iterface u can achieve multiple inheritence and with abstract class can have method definition.

    It is said that with interface u achive less coupling, while its other way with abstract class.

    What exactly does this mean ?? how this is implemented programatically ??

    Cheers,
    Rana

    DB:3.24:Diff Interface And Abstract Class af

    You're not saying this is a reason not to use interfaces, are
    you?I haven't (yet) had this situation happen to me as a result of evolution of my APIs but I would think that's one thing to consider when choosing whether you should go with an abstract class or an interface for a supertype.

  • RELEVANCY SCORE 3.24

    DB:3.24:Interface fd


    can any one tell me what is the actual difference between an abstarct class and interface.when do we use interface and when do we use abstract class in real time environment?

    DB:3.24:Interface fd

    don't encourage this nonsense

  • RELEVANCY SCORE 3.24

    DB:3.24:Interface And Abstract Class Difference 18


    An interface can be used in such a way that we don't know the class of object assigned to a reference of that interface type until runtime. Can we use the abstract class in a similar way too?

    The difference between an abstract class and interface can be listed as
    1. Interface can not have implementation of any method
    2. The usage of interface and class is one other difference
    3. What other differences we have?

    DB:3.24:Interface And Abstract Class Difference 18

    941767 wrote:
    Here we have some more difference...Differences that mean nothing to an experience professional programmer.

  • RELEVANCY SCORE 3.22

    DB:3.22: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:3.22:Interfaces And Abstract Classes fk

    Abstarct class can never be instantiated. Same as interfaces.

    Can be
    subclassed.Same as interfaces.

  • RELEVANCY SCORE 3.21

    DB:3.21:Interface And Abstract Class ac


    hi all,

    A method in an interface consists of access specifiers as public or abstract. what is the difference if the access specifiers for the method is public and abstract.

    regards,
    priya

    DB:3.21:Interface And Abstract Class ac

    That is correct. They must be because interface methods must be overridden when subclassed.

  • RELEVANCY SCORE 3.20

    DB:3.20:Element Substitution Not Working Properly During Unmarshal d3


    Hi everybody,

    I've following situation. I have a project (call it project A) which contains a schema (lets call it the abstract schema). In the abstract schema there is an element which was declared as abstract. Furthermore there is another element (call it container) which shall be able to contain as much "abstract" elements as the user wants to. It obvious that an element could not be abstract, so I've created another project (call it project b) which has a schema (call it concrete schema) whichs imports the abstract schema. In the concrete schema I will have some elements which substitute the abstract element from the abstract schema.

    Now I've an xml document whichs root element is the container (from the abstract schema), and it should contain the non-abstract elements from the concrete schema. So far so good, everything will be validated, there are no errors. But unfortunately the unmarshal progress will not return the expected result. Validation during unmarshal progress is ok as I said but after unmarshalling the xml file, there is no concrete element in the returned result.

    I don't know what could be wrong. Did somebody already worked with element substituion in that way and is able to help me?

    Because its very complicated to describe I've created a minimal testcase (http://www.mailing-list-disaster.com/generic-jobengine.tar.gz) . Just compile both projects and run the using-abstract-engine application.

    Thx for suggestions and with best regards

    Johannes Homuth

    DB:3.20:Element Substitution Not Working Properly During Unmarshal d3

    Hi everybody,

    I've following situation. I have a project (call it project A) which contains a schema (lets call it the abstract schema). In the abstract schema there is an element which was declared as abstract. Furthermore there is another element (call it container) which shall be able to contain as much "abstract" elements as the user wants to. It obvious that an element could not be abstract, so I've created another project (call it project b) which has a schema (call it concrete schema) whichs imports the abstract schema. In the concrete schema I will have some elements which substitute the abstract element from the abstract schema.

    Now I've an xml document whichs root element is the container (from the abstract schema), and it should contain the non-abstract elements from the concrete schema. So far so good, everything will be validated, there are no errors. But unfortunately the unmarshal progress will not return the expected result. Validation during unmarshal progress is ok as I said but after unmarshalling the xml file, there is no concrete element in the returned result.

    I don't know what could be wrong. Did somebody already worked with element substituion in that way and is able to help me?

    Because its very complicated to describe I've created a minimal testcase (http://www.mailing-list-disaster.com/generic-jobengine.tar.gz) . Just compile both projects and run the using-abstract-engine application.

    Thx for suggestions and with best regards

    Johannes Homuth

  • RELEVANCY SCORE 3.18

    DB:3.18:Abstract Class And Interface???? 39


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

    DB:3.18:Abstract Class And Interface???? 39

    P.S. don't be a loser an put up multiple posts, especially on something so easy to do a search on.

  • RELEVANCY SCORE 3.17

    DB:3.17:Abstract And Concrete Project Roles k1



    Can anybody explain what the difference is between abstract and concrete project roles in cProjects.

    There is a field DPR_PART-CONCRETE_ROLE where this is stored, but I did not find out for what this is needed and where it is set.

    DB:3.17:Abstract And Concrete Project Roles k1


    I just found out the difference between the two buttons on the "Roles" tab on task level:

    1. Assign Role

    2. Assign Ressource

    The button "Assign Role" creates a link from the task to the abtract role, while the button "Assign ressource" creates a link to the concrete role.

    Just to let you know.

  • RELEVANCY SCORE 3.17

    DB:3.17:Concrete Classes Implement Abstract Class And Implements The Interface d9


    I have one query..
    In java collection framework, concrete classes extend the abstract classes and implement the interface. What is the reason behind extending the class and implementing the interface when the abstract class actually claims to implement that interface?

    For example :
    Class Vector extends AbstractList and implements List ,....
    But the abstract class AbstractList implements List.. So the class Vector need not explicitly implement interface List.

    So, what is the reason behind this explicit definition...?

    If anybody knows please let me know..

    Thanx
    Rajendra.

    DB:3.17:Concrete Classes Implement Abstract Class And Implements The Interface d9

    Why do you post this question again? You already asked this once in another thread and it has been extensively debated in that thread: http://forum.java.sun.com/thread.jsp?forum=31thread=347682

  • RELEVANCY SCORE 3.17

    DB:3.17:Difference Between Abstract Class And Interface j3


    What is the difference between anabstract class and aninterface ?

    DB:3.17:Difference Between Abstract Class And Interface j3

    Hi,
    Check this link differencebetween an abstract class and an interfacePS.Shakeer Hussain

  • RELEVANCY SCORE 3.16

    DB:3.16:Abstract Class With Abstract Methods Only p7


    Hi,

    What if you had an Abstract class with only abstract methods? How would that be different from an interface? In such case which needs to be chosen?
    I know that abstract class without concrete methods may be a design problem and exists very rarely. But if that was the situation , whether we need to go with
    interface or abstract class? Please clarify.

    Thanks.

    DB:3.16:Abstract Class With Abstract Methods Only p7

    EJP wrote:
    Not really. I see the Java API has many ones that both have abstract and concrete methods.The second statement is irrelevant to the first statement. You have misunderstood what you are saying 'not really' to.Sorry, English is not my native language.

  • RELEVANCY SCORE 3.16

    DB:3.16: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:3.16: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 3.16

    DB:3.16: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:3.16: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 3.15

    DB:3.15: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:3.15: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 3.14

    DB:3.14:Abstract Class And Interface 17



    Please tell me what is Abstract Class and Interface. Please explain with help of simple example and also tell me difference between them.

    DB:3.14:Abstract Class And Interface 17


    hi

    i will suggest u to refer some basic java book , to clear ur basic concept of OOPS , because these principal remain same for all languages that follow OOPS concept .

    and under standing these with java is easier then with ABAP .

    Abstract Class

    class which have atleast 1 method which is declared only , (no definition is given for it in this class is mentioned as Abstract Method )

    and that class is defined as Abstract class

    Interface :

    only declaration of method done here , no method will be defined here , class which will implement this interface will give definition .

    Diff. b/w Abstract Class and Interface :

    ABS Class can have method with there definition , but one method should be there with declartion only.

    Interface will have all method with out definition .

    hpoe this help u .

    reward if helpful.

  • RELEVANCY SCORE 3.13

    DB:3.13:Why All Classes In Javax.Servlet.Jsp Are Abstract? d8


    Hi all,

    I have two questions about how the package was designed:

    1.) why all the classes in the javax.servlet.jsp are abstract? what is the benefits?

    2.) why almost all the methods in the class, such as jspWriter, are abstract too? And we can use these abstract methods in the way we use "concrete" methods?

    3.) the same thing for HTTPServlet class at javax.servlet package.

    Thanks in advance

    yllx

    DB:3.13:Why All Classes In Javax.Servlet.Jsp Are Abstract? d8

    Thanks for the message. In fact, you don't need to reply to the message if you don't have the answer.

    I suspect that this has something to do with the abstract factor design pattern. It allows each container engine to implement the detail based on its own specification. I just need some body to put more details on that.

    Since this happens quite often if the J2EE library, it's good for us to understand why they do this way, and how we can use it in our design.

    yylx

  • RELEVANCY SCORE 3.12

    DB:3.12:Abstract Classes, Interfaces, And Concrete Classes dk


    I have another technical interview tomorrow and somehow I keep getting asked the same question and I feel my answer is not really up to par. The question is:

    "What is the advantage of subclassing an abstract class versus concrete class?"

    "What is the difference of using an interface versus an abstract class, which is better to use?"

    For the first question, I usually answer performance is the advantage because you don't have to instantiate the class.

    For the second question, I usually say that you can put implementation in an abstract class and you can't in an interface. I really can't answer the second part to this question.

    Any ideas?

    DB:3.12:Abstract Classes, Interfaces, And Concrete Classes dk

    Well, no-one's slammed me yet for this reply, so it may help you :-)

    http://forum.java.sun.com/thread.jsp?thread=398928forum=425message=1738126

  • RELEVANCY SCORE 3.11

    DB:3.11: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:3.11: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 3.10

    DB:3.10:Difference Between Factory And Abstract Factory Pattern 1s


    Hi All

    What is the difference between Factory and Abstract Factory Pattern. I often get confuse between them

    Thanks in advance
    anu

  • RELEVANCY SCORE 3.09

    DB:3.09:Interfaces And Abstract Classes 8x


    Whats the difference between an interface and an abstract class.

    DB:3.09: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 3.09

    DB:3.09:Abstract/Concrete Superclasses And Interfaces 1s


    What would you would expect to happen if a class that implements an interface is an abstract superclass? What would you would expect to happen if a class that implements an interface is an concrete superclass? What would be the effect on subclasses of each?

    DB:3.09:Abstract/Concrete Superclasses And Interfaces 1s

    What would you would expect to happen if a class that
    implements an interface is an abstract superclass?Happen? I wouldn't expect anything to happen. (This is the english language right?)

    What would you would expect to happen if a class
    that implements an interface is an concrete
    superclass? Happen? I wouldn't expect anything to happen.

    What would be the effect on subclasses of
    each?No effect. The subclass extends the parent - if it meets the contract for the parent it is done, if it doesn't then there is a problem. That is all the child does. The parent is responsible for what it does not the child.

  • RELEVANCY SCORE 3.08

    DB:3.08: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:3.08: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 3.08

    DB:3.08:What Is The Difference Between Abstract And Interface? d8



    and pls tell me how to know tat

    wen to use static and instance

    DB:3.08: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 3.07

    DB:3.07:Difference Between Pattern And Framework 33


    Hi All,

    What are the various differences between patterns and framework can anybody give me concrete examples ?

    Thanks Regards,
    Kumar.

    DB:3.07:Difference Between Pattern And Framework 33

    Hi,

    One example would be , Struts is a framework, and MVC is the pattern that its design is based on. There are other frameworks that implement MVC. Swing is based on the MVC pattern.

    MVC is explained in a bit more detail at
    http://java.sun.com/blueprints/patterns/MVC.html
    http://java.sun.com/blueprints/patterns/MVC-detailed.html

    hope that helps,
    Sean

  • RELEVANCY SCORE 3.07

    DB:3.07:Re: Difference Between Abstract Class And Interface. f3


    Thanks, jverd. I have got it.

    George

  • RELEVANCY SCORE 3.07

    DB:3.07:Difference Between An Interface And An Abstract Class 9f


    Hey:

    I'm curious, what's the difference between an interface and an abstract class? Thanks.

    DB:3.07:Difference Between An Interface And An Abstract Class 9f

    "You have an abstract class if you want to implement some of the methods in it, but you do not want users to make instances of the class or do not want to implement all of the methods. Take a look at some of the abstract classes in java.util. Nearly all of the methods are implemented already so that it's far easier to create new data structures than if only interfaces were provided. "

    That's what I was looking for. Thanks.

  • RELEVANCY SCORE 3.07

    DB:3.07:Re: What Is The Advantage To Have Constructor In Abstract Classes? c1


    ur explaination is good, However i have question about
    those Abstract class variables? where would they saved
    in memory? because there is no instance of that class?
    but we have only subclasses which called Abstract
    class constructor via super()? where would those
    variable will save in memory?The variables defined in the abstract class will be saved together with the variables of the concrete subclass in the instantiated object. It's the same as with a concrete (not abstract) superclass.

    DB:3.07:Re: What Is The Advantage To Have Constructor In Abstract Classes? c1

    I appreciated ur patient with me for clearing my
    doubts. thanks a lot for u. what is ur job? r u
    student or employee? which is ur place?
    my email is kneethan@hotmail.com, I'm selfemployed. I do contract jobs, write own applications (and play the stock market -:)

    Right now I'm coding on a Java program of my own program called Mint (molecular interactions). You use it to simulate the behaviour of large molecules (proteins, DNA). You can watch them in 3D and turn and twist them and at the same time a simulation is running so all atoms are moving in relation to each other.

    Good luck with Java.

  • RELEVANCY SCORE 3.06

    DB:3.06:Abstract Wsdl Vs Concrete Wsdl fm


    how can we say that WSDL is concrete or abstract?what is difference b/w both WSDLs?what is the purpose of concrete and abstract wsdl?

    DB:3.06:Abstract Wsdl Vs Concrete Wsdl fm

    see :
    http://blogs.oracle.com/aia/entry/aia_11g_best_practices_for_dec
    http://docs.oracle.com/cd/E17904_01/doc.1111/e17364/bestpractices.htm#BABCGHEH

    http://eai.ittoolbox.com/groups/technical-functional/tibco-l/abstractconcrete-wsdl-1091495

    abstract wsdls can be used on designtime, so in that case the backend service don't have to be online to implement your process.
    on runtime the concrete wsdl will be used to lookup for example the actual endpoint (service) and bindings

  • RELEVANCY SCORE 3.06

    DB:3.06: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:3.06: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 3.05

    DB:3.05:Abstract Class And Concrete Class am


    I can't understand why need to creat Abstract class.What's the actual purpose to creat Concrete class to overrides or implements Abstract class methods?
    Help me to understand.

    DB:3.05:Abstract Class And Concrete Class am

    I can't understand why need to creat Abstract
    class.What's the actual purpose to creat Concrete
    class to overrides or implements Abstract class
    methods?
    Help me to understand.A class that's not completely concrete cannot be instantiated (objects cannot be created).

  • RELEVANCY SCORE 3.02

    DB:3.02:Difference B/W Abstract &Amp; Interface jm


    Anyone tell me what is Difference B/w abstract interface. because i m very confiuse.
    plz tell me

    DB:3.02:Difference B/W Abstract &Amp; Interface jm

    Anyone tell me what is Difference B/w abstract
    interface. because i m very confiuse.
    plz tell meNo doubt you're very confused, seeing how you post this kind of vague-ness.
    http://forum.java.sun.com/thread.jspa?threadID=734360

    Maybe this is the wrong field for you. Just maybe.

  • RELEVANCY SCORE 3.02

    DB:3.02: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:3.02: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 3.02

    DB:3.02:Abstract Service c9


    Hi all,

    In OCAP there is a concept of Abstract Service
    Each abstract service has to be assocaited with service context. How many service context can we create.

    What is difference between Abstract Service and Broadcast Service?

    Are they both same?.

    If yes, each unbound and host device manufacturer applications have to be associated with Abstract service?
    For example take EPG as an Absract Service, in that case the preview window in EPG shows the broadcast service.

    Is it possible to show both abstract service and broadcast service at a time?.

    Any OCAP experts Pls clarify my above doubts.

    Thanks,
    Rahul

    DB:3.02:Abstract Service c9

    I think you need to read the OCAP specification more carefully. Particularly 10.2.2.2.1 point c).

  • RELEVANCY SCORE 3.02

    DB:3.02:Difference Between Abstract Factory And Factory p3


    Hi,
    If anyone provide difference between abstract factory and Factory pattern with example it could be helpful
    Thanks,

    DB:3.02:Difference Between Abstract Factory And Factory p3

    Hi,
    i tried to answer differences betwen 3 factories pattern here:factory family

  • RELEVANCY SCORE 3.02

    DB:3.02:Requirement Of A Abstract Message Interface fz


    Hello,I wonder when to use abstract message interfaces?The documentations says:An abstract message interface has no implementation in an application system. You cannot generate a proxy for this interface type. You use abstract interfaces in business processes, for example, to receive or send messages from application systems. You can use the same abstract interface to receive or to send.******************************************************What does IMPLEMENTATION mean in this context? Can anybody discribe a concrete need for abstract message interfaces?Thank You

    DB:3.02:Requirement Of A Abstract Message Interface fz

    Hi Mario,you only use those interfaces inside a BPM:send step, receive step, transformations etc(no other use) - you cannot create proxies from it- you must have an normal (not abstract) interfaceto send data to XI or to receive data (so once you create everything inside your integration process - with the use of abstract interfaces)inside ID you still have to use standard interfaces (outbound or inbound) Regards,michalMessage was edited by: Michal Krawczyk

  • RELEVANCY SCORE 3.02

    DB:3.02:Abstract Class Or Interface ? 11


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

    DB:3.02: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 3.02

    DB:3.02:Difference Between Abstract Class And Interface ca


    Hi everyone,

    CAn anyone explain why the following happen????

    --------------------------------------------------------------------------------
    Abstract class can have a constructor, Interface cannot.
    Abstract class can have static methods, Interface cannot.
    --------------------------------------------------------------------------------

  • RELEVANCY SCORE 3.02

    DB:3.02:Core Java 83


    what is differernce between abstract class and interface?

    DB:3.02:Core Java 83

    jwenting wrote:
    maybe an attempt at counting only posts which make any kind of sense at all?Where did the '1' come from then?

  • RELEVANCY SCORE 3.01

    DB:3.01:Re: Difference Between Com.Mysql.Jdbc.Connection And Java.Sql.Connection dc


    The one is an abstract interface and the other is a concrete implementation class of it.

    You should never have the need to declare implementation specific classes of abstract API's such as JDBC. Just declare them using the abstract API. This way you don't need to change your code whenever you change the implementation (in this specific case, the JDBC driver).

    That's the whole idea of polymorphism. Didn't you have learnt about it during your Java lessons?

    DB:3.01:Re: Difference Between Com.Mysql.Jdbc.Connection And Java.Sql.Connection dc

    I have been writing database code for a while. However I do not know the difference between the classes provided by the com.mysql library and the java.sql library. Would someone care to educate me on the differences and possible advantages. Sincerely, Chem E

  • RELEVANCY SCORE 3.00

    DB:3.00:Concrete Class 8c


    What is concrete class?

    DB:3.00:Concrete Class 8c

    public class Concrete implements BuildingMaterial {
    }

  • RELEVANCY SCORE 2.99

    DB:2.99:Re: Compiler Error!!! 1z


    First, let me say that what you seem to be doing seems intuitively wrong. Normally you derive a concrete class from an abstract base, but what you seem to be doing is deriving an abstract class from a concrete base. I am not even sure this is allowed, which may be a part of the problem.

    Secondly, are you sure the method is in EfzinAbstractUpdatableFrame and not in EfzinInternalFrame?

    DB:2.99:Re: Compiler Error!!! 1z

    DrClap, You are correct the EfzinAbstractUpdatableFrame.this cease the compiler error message.
    Thank you all.

  • RELEVANCY SCORE 2.99

    DB:2.99:What Is The Difference Between Abstract Class And Interface af


    hi,recently i went for an interview they ask me what is abstract class ,interface and its difference
    I said abstract class contain abstact method ,abstract method is a method with no body.Abstract class cannot be instantiated.Abstract class is a base class it required derived class for the implementation of method.
    Interface is a syntactical contract that all derived class should follow
    it define properties ,method,events which are known as member of interface.
    Then They asked me what is the difference between them. I said
    abstract class interface
    1.abstact class can implement method 1.interface cant
    2.abstact class can contain constructor, 2.interface cant
    destructor
    3.abstract class cannot support multiple 3.interface support
    inheritance
    etc
    Then they said some different answer I said dont no.
    Then they ask me when i should make abstract class for an project and when
    i should make interface.
    I said if suppose there is two class which must be having method with different logic then we sholud make abstract class.
    and if suppose we have two class having method .with different logic then we can make interface .
    Am i correct with my explaination.if not correct me .please provide me that when should we create abstract class and interface and what is difference .please help me

    DB:2.99:What Is The Difference Between Abstract Class And Interface af

    I would focus the answer on the distinction that you cant add an abstract class to an existing class like you can an interface.

  • RELEVANCY SCORE 2.98

    DB:2.98: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:2.98: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 2.96

    DB:2.96: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:2.96: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 2.95

    DB:2.95:Wsdl's sp


    Hi All,

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

    Can anybody help to understand this?

    - Thanks

    DB:2.95: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 2.95

    DB:2.95: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 2.94

    DB:2.94: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:2.94: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 2.94

    DB:2.94:Abstract Class Vs Interface And Importance Of Using xm



    Hi All,

    I want to know what is the difference between Abstract class and Interface.

    and what is the importance of using them.

    Moderator message: please search for available information/documentation.

    Edited by: Thomas Zloch on Sep 27, 2011 1:55 PM

    DB:2.94:Abstract Class Vs Interface And Importance Of Using xm


    Please refer to this thread, already this is discussed in forums

    [ABAP Objects.. Abastract Interface Class;

    Thanks

    Pavan

  • RELEVANCY SCORE 2.93

    DB:2.93:Reason Needed as


    why abstract classes have concrete methods

    DB:2.93:Reason Needed as

    Before anybody tries to help this bozo, please examine his post history.

    Go away, mukesh.

    You're just asking others to spoon-feed you stuff that you should have been studying and learning all along. You were either too lazy or too inept to learn your course material when you should have, so deal with the consequences.

  • RELEVANCY SCORE 2.93

    DB:2.93: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:2.93: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 2.93

    DB:2.93:What Is The Exact Difference Between Abstract Classes And Interface 7m


    What is the exact difference between abstract classes and interface in real scenario???

    Plz could you give a practical example???

    Thanks

    DB:2.93:What Is The Exact Difference Between Abstract Classes And Interface 7m

    At least your head doesn't make a plonk sound.Mine just makes a splutchy bursting watermelon type sound.

    To the original poster - to make things simple, if there is any doubt about which you should use, use an interface. If the situation calls for an abstract class, you will know that an interface is the wrong choice, because it will be impossible to do what you want to do with an interface.

    Drake

  • RELEVANCY SCORE 2.92

    DB:2.92:Help Pls! 87


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

    Thanx!

    DB:2.92: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 2.92

    DB:2.92: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:2.92: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 2.92

    DB:2.92:Interfaces Vs. Abstract Classes ps


    1) is there a difference between an interface (that has methods to override) and an abstract class?

    2) also what is the purpose of static members, static methods, and static classes??

    3) is there a distinction between an Abstract Data Type and User Defined Data Types?

    DB:2.92:Interfaces Vs. Abstract Classes ps

    Read Core Java Fundamentals Volume 1 by Horstmann Cornell from Sun Micro. Press release.
    Its a must to know them very well from reading it from the above book rather than relying on what you hav learnt from a discussion board. by the way, its just a personal statement, not intended to offend any fellowmates of the discussion board.

    cheers

    -tamoghna

  • RELEVANCY SCORE 2.92

    DB:2.92:Difference: s1


    Consider the scenario:

    There exists a abstract implementation (say 'AbstractImpl' ) of a interface (say 'InterfaceA'). Concrete implementaion (say 'ConcreteImpl') extends 'AbstractImpl'. (This is sometimes called Template Design Pattern).

    What is the difference between:
    1.
    AbstractImpl a=new ConcreteImpl();2.
    InterfaceA b = new ConcreteImpl();Does it makes a difference on either way of instantiation? What is a better approach? and Why?

    DB:2.92:Difference: s1

    In any event this has nothing to do with the OPs
    question. the question was about the common practice
    of creating an interface and then creating an default
    abstract version of that class (see AbstractList).Based upon the example I believe the OP's confusion, if not their explicit question, is over how type should be declared. For example, whether or not you declare a ListString or an ArrayListString.

    Also, as a bit of further explanation to the OP it's not so much the declaration that is important as it is your method signatures. If your method specifies it returns an InterfaceA then you can have it return any InterfaceA, if the method returns an AbstractImpl you can never change it to a different InterfaceA that's not necessarily an AbstractImpl. The declaration can still be important, but that's only going to affect the class it's delared in (assuming external classes don't access it directly). The method signature will get you into trouble as every client will be affected.

  • RELEVANCY SCORE 2.91

    DB:2.91:Difference Between Catos And Ios d3



    Hi friends,

    Can someone tell me the concrete difference between CatOS and IOS?

    DB:2.91:Difference Between Catos And Ios d3


    Here's one for the 6500 series. In addition to VTPv3, it might also be worth mentioning that the case is the same for GVRP, which runs Dell switches.

    http://www.cisco.com/application/pdf/en/us/guest/products/ps708/c1244/ccmigration_09186a00800c8441.pdf

  • RELEVANCY SCORE 2.91

    DB:2.91:Difference Between Inheritance And Abstract Class 9s


    difference between inheritance and abstract class

    DB:2.91: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 2.91

    DB:2.91:Interface Abstract And Concrete Class d1


    Do i have the right in java to extend an abtract class to a concrete class and also to implement the ineface
    in the concrete class

    What am i saying is

    public class concrete extends abstract implements interface ??

    DB:2.91:Interface Abstract And Concrete Class d1

    That's what inheritance in Java is all about Yup, generally its a very logical and robust design model that is right at the heart of OOP. Extending an abstract defined class also involves (though not necessarily) 'encapsulation' as well as inheritance. An interface on the other hand is a means to define methods, ie: you create the conditions of what you want to do, with deferred implementations - in other words there are no { - to stuff here -} code blocks. Absract classes on the other hand may or may not have deferred methods and implemented methods inherited by the subclass or inheriting class are allowed.

    It's common convention to let class and interface
    names start with a capital letter.It is highly illogical to do anything otherwise.