How is this used in Scala?
We use the this keyword when we want to introduce the current object for a class. Then, using the dot (.) operator, we can refer to instance variables, methods, and constructors using this keyword. this keyword is also used with auxiliary constructors.
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Can we use this keyword in the default constructor?
Using this with a constructor From within a constructor, you can also use the this keyword to call another constructor in the same class. Doing so is called an explicit constructor invocation. Constructors provide a default value for any member variable whose initial value is not provided by an argument.
What is a method in Scala?
A Scala method is part of a class that has a name, a signature, optionally some annotations, and some bytecode where, as a function in Scala, it is a complete object that can be assigned to a variable. In other words, a function, which is defined as a member of some object, is called a method.
Can we call the parameterized constructor from the default constructor?
You can’t call a default constructor once you’ve created a constructor that takes arguments. You’ll need to create the no-argument constructor yourself to make a call from the parameterized constructor.
How do you call a helper constructor in Scala?
In the Scala program, constructors other than the main constructor are known as helper constructors. We are allowed to create any number of helper constructors in our Scala class, but a Scala class contains only one main constructor. Helper constructors are defined as methods on the class with the this keyword.
Can a primary constructor call a helper constructor?
Like method overloading, all helper constructors must use the same name: “this”. Each Auxiliary Constructor must have a different signature, that is, a list of Different Parameters. Each Auxiliary Constructor must call a previously defined constructor: it can be either a Primary Constructor or Auxiliary Constructors.
How to create a private constructor in Scala?
In Scala, we can make a main constructor private by using a private keyword between the class name and the constructor’s parameter list. // private constructor with two arguments class GFG private (name: String, class:Int) { // code.. } // private constructor with no argument class GFG private { // code…
What happens when parameters are declared in a constructor in Scala?
If the parameters in the constructor’s parameter list are declared using val, then the value of the fields cannot change. And Scala also generates a getter method for that field.