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Why Can't We Instantiate An Abstract Class In Java


Browse other questions tagged java abstract-class or ask your own question. Not the answer you're looking for? You don't want to instantiate A. iptables not dropping by IP and port? this contact form

Why didn’t Japan attack the West Coast of the United States during World War II? It's just that, that class is given a name only after compilation by the compiler. Join them; it only takes a minute: Sign up Interview: Can we instantiate abstract class? The nth numerator Algorithm of checking whether an element is present in a merkle tree Am I interrupting my husband's parenting?

Why Can't We Instantiate An Abstract Class In Java

Not the answer you're looking for? abstract class Vehicle { public abstract void runMotor(); } class SUV extends Vehicle { public void runMotor() { System.out.println( this.getClass().getName() + ": Need more gas"); } } class Hybrid extends Vehicle Join them; it only takes a minute: Sign up Abstract classes cannot be instantiated up vote -1 down vote favorite Abstract classes cannot be instantiated. B b = new B(); or A a = new B(); //Note you are not instantiating A, here class A variable is referencing the instance of class B share|improve this answer

java oop class object abstract share|improve this question edited May 23 '14 at 6:59 user2864740 35.5k43982 asked Dec 2 '12 at 16:01 Ravi 7,7792162102 5 possible duplicate stackoverflow.com/questions/4579305/… –AsheeshR Dec FAQs Search RecentTopics FlaggedTopics HotTopics Best Topics Register / Login Post Reply Bookmark Topic Watch Topic New Topic programming forums Java Java JSRs Mobile Certification Databases Caching Books Engineering Languages Frameworks Why cast an A-lister for Groot? Abstract Class Can Have Constructor i.e.

EDIT: Ask him to test this public static final void main(final String[] args) { final my m1 = new my() { }; final my m2 = new my() { }; System.out.println(m1 Then you can make a factory, which returns an instance of this abstract class (actually his implementor). Add-in salt to injury? navigate here What exactly are sleeping stalls versus waiting-rooms, for airport layovers?

If you don't want to create a new class you can instead use an anonymous class: AbstractFoo foo = new AbstractFoo(param, for, constructors){ @Override public void foo(){ //override and implement methods Can Abstract Class Be Inherited That's not possible, you can't create abstract objects 1.1.2. share|improve this answer edited Jun 7 '13 at 19:11 Community♦ 11 answered Jan 2 '11 at 16:33 Darin Dimitrov 694k16225322389 Can you please elaborate on factory pattern or give And then you are invoking the method on your abstract class reference pointing to subclass object.

Instantiate Abstract Class C#

Problems with the examples? You can take advantage of the similarities and declare all the graphic objects to inherit from the same abstract parent object (for example, GraphicObject) as shown in the following figure.

Classes Why Can't We Instantiate An Abstract Class In Java However, with abstract classes, you can declare fields that are not static and final, and define public, protected, and private concrete methods. Can An Interface Be Instantiated That means every person should know how to speak (implement the speak()).

share|improve this answer answered Jan 4 '14 at 7:24 vikas agrahari 29814 add a comment| up vote 3 down vote It's impossible to instantiate an abstract class. weblink This is useless... How can I check that the voltage output from this voltage divider is 2.25V? pubic abstract void doSomething(); //This abstract method doSomething is required to be implemented via all the sub-classes. Abstract Classes Can Be Final

Since your a class have no abstract methods, there is no difference what so ever from a subclass-perspective. (The only difference is that if a is abstract it may no longer A implements all the abstract methods. Complaints? http://kshelper.com/abstract-class/cannot-instantiate-abstract-class-php.html share|improve this answer edited Nov 20 '14 at 9:25 answered Nov 20 '14 at 9:13 ratchet freak 20.4k24280 If your abstract class don’t contain any abstract method, you can

it could be color. Abstract Classes May Also Define Abstract Methods share|improve this answer answered Dec 3 '12 at 9:14 Abhi_Mishra 2,58231328 add a comment| up vote 11 down vote Technical Answer Abstract classes cannot be instantiated - this is by definition This line has really confused me, any and all help is much appreciated.

We haven't given the definition of a method and therefore, if it had allowd the creation of the object, there was no return address to pop the function from the stack

An example of a class in the JDK that implements several interfaces is HashMap, which implements the interfaces Serializable, Cloneable, and Map. Does トイレ refer to the British "toilet" or the American "toilet"? If I receive written permission to use content from a paper without citing, is it plagiarism? .abstract Classes May Also Define Abstract Methods Horses and cows are mammals, ducks and gease are fouls so.....

We can create Subclasses to Abstract classes. Related 367Can an abstract class have a constructor?303Difference between abstract class and interface in Python853Interface vs Abstract Class (general OO)474Creating an abstract class in Objective-C962What is the difference between an interface Hope you will satisfied. his comment is here what was I going to say again?

Who knows - maybe you're "both right" but working off slightly different meanings for terms?? Is it professional to disagree with a superior's technical decision in front of others? Just before a reference to the newly created object is returned as the result, the indicated constructor is processed to initialize the new object using the following procedure: You can read people other than the OP may read this hoping for a thorough answer. –Alex Lynch Nov 16 '12 at 1:03 | show 2 more comments up vote 1 down vote A

How to deal with a coworker that writes software to give him job security instead of solving problems? but to provide understanding, you must explain why you allowed to instantiate the ConcreteClass and not the AbstractClass. –Alex Lynch Nov 16 '12 at 0:31 You can even use What is the definition of "rare language"? Suggestions?

B has at least an abstract method 1.2.1. I argued a bit on this. share|improve this answer answered Apr 24 at 1:46 Bharti Rawat 345214 NO ..I m not satisfied ..pls share some more insights –eRaisedToX Sep 4 at 16:41 add a comment| How small could an animal be before it is consciously aware of the effects of quantum mechanics?

To know whether you have the confidence to stand up against your seniors in situations similar to this. share|improve this answer edited Jan 5 at 17:05 answered Apr 21 '15 at 19:06 Ketan G 2251215 add a comment| protected by Rohit Jain Jul 2 '13 at 12:12 Thank you B doesn't have abstract methods 1.1.1. Note:Methods in an interface (see the Interfaces section) that are not declared as default or static are implicitly abstract, so the abstract modifier is not used with interface methods. (It can

Isn't it an abstract class? 0 Default constructor significance in this scenario -2 Can we instantiate an abstract class? Compliments?