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 moreWhy call to this () must be the first statement in constructor?
this or super needs to be first statement in constructor so that child class constructor invokes parent class constructor first . This is required to initialize any variable in parent class before doing any thing in child constructor.
Read moreWhat is the first statement in constructor?
The reason is that “Constructor call must be the first statement in a constructor”.
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
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