Can constructor be static?

Java constructor can not be static

One of the important property of java constructor is that it can not be static. We know static keyword belongs to a class rather than the object of a class. A constructor is called when an object of a class is created, so no use of the static constructor.

Can we make constructors static?

No, we cannot define a static constructor in Java, If we are trying to define a constructor with the static keyword a compile-time error will occur. In general, static means class level. A constructor will be used to assign initial values for the instance variables.

Can constructor be static and non-static?

Prerequisite: Constructors in C#

Declaration: Static constructors are declared using a static modifier explicitly while all other remaining constructors are non-static constructors. Non-static constructors can also be called as Instance Constructors as they need instance to get executed.

What happens if constructor is static?

The user has no control on when the static constructor is executed in the program. A static constructor is called automatically. It initializes the class before the first instance is created or any static members declared in that class (not its base classes) are referenced.

Can a constructor be final or static?

No, a constructor can't be made final. A final method cannot be overridden by any subclasses.

Can a Constructor be static in Java ?

Can a constructor be abstract?

Since you cannot override a constructor you cannot provide body to it if it is made abstract. Therefore, you cannot use abstract keyword with the constructor.

Why constructor is static in Java?

In Java, a constructor is not allowed to be abstract, final, static, native, or strictfp. So, there is no static constructor in Java. A static constructor used to initialize static data means the specified task will execute only once throughout the program.

Can constructor be virtual?

In C++, constructor cannot be virtual, because when 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 constructor be void?

Note that the constructor name must match the class name, and it cannot have a return type (like void ). Also note that the constructor is called when the object is created.

Can we overload constructor?

Yes! Java supports constructor overloading. In constructor loading, we create multiple constructors with the same name but with different parameters types or with different no of parameters.

Is constructor static or nonstatic?

Java constructor can not be static

One of the important property of java constructor is that it can not be static. We know static keyword belongs to a class rather than the object of a class. A constructor is called when an object of a class is created, so no use of the static constructor.

Can we declare constructor as private?

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 a constructor be static in C++?

C++ doesn't have static constructors, as Java or C# does, so you usually have to initialize the static data members one by one (independently). This is a limitation because you may want to initialize several static data members in the same loop or algorithm, for example.

Why constructor is not overridden?

Constructor Overriding is never possible in Java. This is because, Constructor looks like a method but name should be as class name and no return value. Overriding means what we have declared in Super class, that exactly we have to declare in Sub class it is called Overriding.

Can constructor be overridden?

Constructor looks like method but it is not. It does not have a return type and its name is same as the class name. But, a constructor cannot be overridden. If you try to write a super class's constructor in the sub class compiler treats it as a method and expects a return type and generates a compile time error.

Can we use this () and super () in a constructor?

“this()” and “super()” cannot be used inside the same constructor, as both cannot be executed at once (both cannot be the first statement). “this” can be passed as an argument in the method and constructor calls.

Can constructor throw an exception?

The short answer to the question “can a constructor throw an exception in Java” is yes! Of course, properly implementing exceptions in your constructors is essential to getting the best results and optimizing your code.

Can we overload constructor in derived class?

Can constructors be overloaded in derived class? Explanation: The constructor must be having the same name as that of a class. Hence a constructor of one class can't even be defined in another class. Since the constructors can't be defined in derived class, it can't be overloaded too, in derived class.

Can a constructor return a value?

No, constructor does not return any value. While declaring a constructor you will not have anything like return type. In general, Constructor is implicitly called at the time of instantiation.

Can a constructor be 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 destructor as private?

Yes, destructor can be private and it is not true that class cannot be instantiated.

Can virtual function static?

A virtual function cannot be global or static because, by definition, a virtual function is a member function of a base class and relies on a specific object to determine which implementation of the function is called.

Should a factory be static?

No, factory class by default shouldn't be static. Actually, static classes are not welcomed in OOP world since they can also convey some state and therefore introduce global application state. If you need only one factory object to be present, you can control it's creation through singleton pattern.

Why factory method is static?

The constructors are marked private, so they cannot be called except from inside the class, and the factory method is marked as static so that it can be called without first having an object.

Can we use final keyword before constructor?

declaring constructor as final

In other words, constructors cannot be inherited in Java, therefore, you cannot override constructors. So, writing final before constructors make no sense. Therefore, java does not allow final keyword before a constructor.