What happens when default constructor is called in Java?

What is a default constructor and when is it called?

A constructor is always called when constructing a new object, and a constructor of every superclass of the class is also called. If no constructor is explicitly called, the default constructor is called (which may or may not be declared).

What happens when a constructor is called in Java?

In Java, a constructor is a block of codes similar to the method. It is called when an instance of the class is created. At the time of calling constructor, memory for the object is allocated in the memory. It is a special type of method which is used to initialize the object.

Can a default constructor be called?

A default constructor is a constructor which can be called with no arguments (either defined with an empty parameter list, or with default arguments provided for every parameter). A type with a public default constructor is DefaultConstructible.

What does default constructor do?

A default constructor is a constructor that either has no parameters, or if it has parameters, all the parameters have default values. … This constructor is an inline public member of its class. The compiler will implicitly define A::A() when the compiler uses this constructor to create an object of type A .

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When should a default constructor be removed?

Deleting the default constructor of a class is a good idea when there are multiple choices for the default or uninitialised state.

Can constructor be 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.

What is the difference between method and constructor?

A Constructor initializes a object that doesn’t exist. A Method does operations on an already created object. A Constructor’s name must be same as the name of the class. … A class can have many Constructors but must not have the same parameters.

Is overriding possible in Java?

In Java, methods are virtual by default. We can have multilevel method-overriding. Overriding vs Overloading : … Overriding is about same method, same signature but different classes connected through inheritance.

Can constructor be overloaded?

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.

Can you have a constructor with all default arguments?

It is possible to have a constructor with default arguments.. It means that if the constructor is defined with n parameters, we can invoke it with less than n arguments specified in the call.

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