The compiler automatically provides a public no-argument constructor for any class without constructors . This is called the default constructor. If we do explicitly declare a constructor of any form, then this automatic insertion by the compiler won’t occur.
Read moreIs it necessary to call super ()?
There is an implicit call to super() with no arguments for all classes that have a parent – which is every user defined class in Java – so calling it explicitly is usually not required . However, you may use the call to super() with arguments if the parent’s constructor takes parameters, and you wish to specify them.
Read moreWhat happens if we don’t use constructor for a class?
No-argument constructor If we don’t define a constructor in a class, then the compiler creates a default constructor(with no arguments) for the class .
Read moreWhat is the purpose of super ()?
The super() in Java is a reference variable that is used to refer parent class constructors . super can be used to call parent class’ variables and methods. super() can be used to call parent class’ constructors only.
Read moreShould be the first statement in the constructor?
The Eclipse compiler says “Constructor call must be the first statement in a constructor”. So, it is not stopping you from executing logic before the call to super . It is just stopping you from executing logic that you can’t fit into a single expression. There are similar rules for calling this().11 Tem 2019
Read moreWhat if superclass has no constructor?
If the parent has no constructor (Object does have one), the compiler will reject the program . But then, Object is a (direct or indirect) superclass of every class in Java. Suppose, we have a class A , which does not extend any class explicitly, so it implicitly extends Object .
Read moreIs super class constructor always called?
Before you can initialize an object in a constructor, the object’s parent constructor must be called first. … The compiler automatically inserts superclass constructor calls in both constructors .
Read more