Can we make constructor static?
Last Update: April 20, 2022
This is a question our experts keep getting from time to time. Now, we have got the complete detailed explanation and answer for everyone, who is interested!Asked by: Mackenzie Wintheiser
Score: 4.7/5 (70 votes)
One of the important property of java constructor is that it can not be static. ... A constructor is called when an object of a class is created, so no use of the static constructor. Another thing is that if we will declare static constructor then we can not access/call the constructor from a subclass.
What happens if constructor is static?
If we declare a constructor as static, then it can not be accessed by its subclasses and will belong to a class level only. The program will not be compiled and throw a compile-time error. Let's understand it with an example: StaticConstructorExample.
Can constructor be private or static?
Yes, we can declare a constructor as private. If we declare a constructor as private we are not able to create an object of a class. We can use this private constructor in the Singleton Design Pattern.
Can we make constructor static in CPP?
C++ doesn't have static constructor. But a static constructor can be emulated by using a friend class or nested class as below.
Can a constructor be final?
No, a constructor can't be made final. A final method cannot be overridden by any subclasses. ... But, in inheritance sub class inherits the members of a super class except constructors. In other words, constructors cannot be inherited in Java therefore, there is no need to write final before constructors.
Can We Declare Constructor As Static?
Can constructor be virtual in C++?
In C++, the constructor cannot be virtual, because when a constructor of a class is executed there is no virtual table in the memory, means no virtual pointer defined yet. So, the constructor should always be non-virtual.
Can we override static method?
Static methods cannot be overridden because they are not dispatched on the object instance at runtime. The compiler decides which method gets called. Static methods can be overloaded (meaning that you can have the same method name for several methods as long as they have different parameter types).
Can we have static class?
The answer is YES, we can have static class in java. In java, we have static instance variables as well as static methods and also static block. Classes can also be made static in Java. In java, we can't make Top-level (outer) class static.
Can we inherit a class with private constructor?
What is Private Constructor? ... If a class has one or more private constructor and no public constructor then other classes are not allowed to create instance of this class; this means you can neither create the object of the class nor can it be inherited by other classes.
Why constructor is non static?
In principle when you create a new object (by using new operator), JVM will allocate some memory for it and then call a constructor on that newly created object. Also JVM makes sure that no other method is called before the constructor (that's what makes it special). Constructors are NOT static functions.
Is constructor inherited?
Constructors are not members, so they are not inherited by subclasses, but the constructor of the superclass can be invoked from the subclass.
Can we make constructor private?
Yes. Class can have private constructor. Even abstract class can have private constructor. By making constructor private, we prevent the class from being instantiated as well as subclassing of that class.
Can we create object for private class?
1 Answer. yes. private is an access modifier, as you might have learned that restricts member to be access just within declaring scope. So as a member of another class , private class can be accessed in that class only.
Can we use this () and super () in a method?
both this() and super() can not be used together in constructor. this() is used to call default constructor of same class.it should be first statement inside constructor. super() is used to call default constructor of base class.it should be first statement inside constructor.
Can static class be inherited?
Static classes are sealed and therefore cannot be inherited. They cannot inherit from any class except Object. Static classes cannot contain an instance constructor.
When should you make a class static?
Use a static class as a unit of organization for methods not associated with particular objects. Also, a static class can make your implementation simpler and faster because you do not have to create an object in order to call its methods.
What is a class when do we declare a member of a class static?
When we declare a member of a class as static it means no matter how many objects of the class are created, there is only one copy of the static member. A static member is shared by all objects of the class. All static data is initialized to zero when the first object is created, if no other initialization is present.
Can object be static?
5 Answers. The static keyword in Java means that the variable or function is shared between all instances of that class, not the actual objects themselves. Thus anything we access here without creating an instance of the class Flavor1Demo has to be a static resource.
Can we override static method Why?
Can we override a static method? No, we cannot override static methods because method overriding is based on dynamic binding at runtime and the static methods are bonded using static binding at compile time. So, we cannot override static methods.
Can we override main method?
No, we cannot override main method of java because a static method cannot be overridden. ... So, whenever we try to execute the derived class static method, it will automatically execute the base class static method. Therefore, it is not possible to override the main method in java.
Can we override private method?
No, we cannot override private or static methods in Java. Private methods in Java are not visible to any other class which limits their scope to the class in which they are declared.
Can we make a virtual constructor?
Constructor can not be virtual, because when constructor of a class is executed there is no vtable in the memory, means no virtual pointer defined yet. Hence the constructor should always be non-virtual.
Can a class have virtual destructor?
Destructors in the Base class can be Virtual. Whenever Upcasting is done, Destructors of the Base class must be made virtual for proper destrucstion of the object when the program exits. NOTE: Constructors are never Virtual, only Destructors can be Virtual.
Why do we need virtual constructors in C++?
The compiler must be aware of the class type to create the object. In other words, what type of object to be created is a compile-time decision from the C++ compiler perspective. ... The objective of the virtual constructor is to decouple object creation from its type.
Is a constructor an object?
In class-based object-oriented programming, a constructor (abbreviation: ctor) is a special type of subroutine called to create an object. It prepares the new object for use, often accepting arguments that the constructor uses to set required member variables. ... Immutable objects must be initialized in a constructor.