Is Empty constructor necessary?

An empty constructor is needed to create a new instance via reflection by your persistence framework. If you don’t provide any additional constructors with arguments for the class, you don’t need to provide an empty constructor because you get one per default.

Is it mandatory to use constructors in a class?

Users do not need to write constructors for every class. A constructor can be declared using any of the access modifiers. It is mandatory to have a constructor with the right access modifier. However, the compiler supplies a default if an access modifier is not defined in the class and a constructor is not declared.

Can a class have an empty constructor?

You can also have a private parameterless constructor as well that is instrumental in making singleton classes. If you don’t need a parameterless constructor, don’t add one with an empty body. However, if someone wants to serialize/deserialize objects of your class, then you’ll need a parameterless constructor.

What happens if there is no constructor defined in a class?

If we don’t define a constructor in a class, then the compiler creates default constructor(with no arguments) for the class. And if we write a constructor with arguments or no-arguments then the compiler does not create a default constructor.

Are constructors necessary?

Java doesn’t require a constructor when we create a class. However, it’s important to know what happens under the hood when no constructors are explicitly defined. The compiler automatically provides a public no-argument constructor for any class without constructors. This is called the default constructor.

What is the use of empty constructor in C#?

If you declare an empty constructor, the C# compiler will not dynamically generate a parameter-less constructor. If you do not use an access modifier with the constructor, it will also become a private constructor by default. Using the private keywords makes it obvious for developers by explicitly stating the type.

Why do we need constructor in C#?

The main use of constructors is to initialize the private fields of the class while creating an instance for the class. When you have not created a constructor in the class, the compiler will automatically create a default constructor of the class.

Is constructor compulsory?

We know that C++ class constructor is called when we create an object of a class. If a class is not required to initialize its data member or does not contain data member, there is no need to write empty constructor explicitly. On class object creation, default constructor implicitly called will be enough.

Do classes need constructors C#?

All classes have constructors by default: if you do not create a class constructor yourself, C# creates one for you. However, then you are not able to set initial values for fields.

Is constructor necessary in C#?

Constructor is a method in A class which will get executed when its object is created. So by default there will be one constructor of the class and it’s mandatory. This is how we create a constructor of a class: class Constructor.

What happens if we dont use constructor?

Could any one show what would happen without constructor in Java? you wouldn’t be able to create objects/instances of classes, basically: you would only be able to use primitive datatypes. Even you don’t write any constructor, a default constructor exists there.

Can a class have no constructor C++?

If your class has no constructors, C++ will automatically generate a public default constructor for you. This is sometimes called an implicit constructor (or implicitly generated constructor). The Date class has no constructors.