Which is a method that is called when a new instance of a class is created?
Now that we can create both classes and custom methods, let's explore a special type of method called a constructor. We can use constructors to DRY up our code and make the process of instantiating new objects much quicker. Show A constructor is a method that is called when a new instance of a class is created. Any information regarding the initial setup of a new object can be included in a constructor. Writing Constructor MethodsLet's walk through adding a constructor to our
Constructors look a lot like other methods. Our constructor can take multiple parameters and also has an access modifier that we've set to 0 containing a Car object's make, and so on.When we call our constructor, we will pass in arguments for a 3, 4, and 5. A Car will be instantiated with the fields set to the arguments we've passed in. Note that the object's fields are in PascalCase while the constructor method's parameters are lowerCamelCase.Our constructor method will also return an object of the class type it belongs to — in this case, our constructor will return an instance of Calling Constructor MethodsConstructors create new instances of a class when the 8 keyword is used. 8 denotes that we're creating a new instance of this class:
When our dealership gets another
Let's use our new constructor in the command line interface of our car dealership application. We can refactor this area of our program:
We will use our new constructor instead:
The entire updated file should look like this:
Constructors allow us to write cleaner and DRYer code. Moving forward, use constructor methods to create instances of custom classes in all your applications. What is called when an instance of a class is created?The creation of an instance is called instantiation. An object may be varied in a number of ways. Each realized variation of that object is an instance of its class. That is, it is a member of a given class that has specified values rather than variables.
Which method of a class is used for creating an instance of the class?Using newInstance() Method of Class class
It returns a newly created instance of the class represented by the object. It internally uses the newInstance() method of the Constructor class.
What method gets called when a class object is created?The constructor method is a special method for creating and initializing an object created with a class . There can only be one special method with the name "constructor" in a class.
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