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Help me understand Parameterized Constructors

This solution is very confusing at the previous lesson it says that “In a parameterized constructor, we pass arguments to the constructor and set them as the values of our data members” What does this mean? Does it mean that after setting the default constructor, we can change the value with a parameterized constructor?

For me is just making the code too long and ChatGPT is just confusing me more.


Course: https://www.educative.io/collection/10370001/5692479535841280
Lesson: https://www.educative.io/collection/page/10370001/5692479535841280/5783412147224576

Hi @Emilio_Parra !!

// Car class
class Car {

  // Private Fields
  private String carName;
  private String carModel;
  private String carCapacity;

  // Default Constructor
  public Car() {
    this.carName = "";
    this.carModel = "";
    this.carCapacity = "";
  }

  // Parameterized Constructor 1
  public Car(String name, String model) {
    this.carName = name;
    this.carModel = model;
  }

  // Parameterized Constructor 2
  public Car(String name, String model, String capacity) {
    this(name, model); // calling parameterized Constructor
    this.carCapacity = capacity; // Assigning capacity
  }

  // Method to return car details
  public String getDetails() {
    return this.carName + ", " + this.carModel + ", " + this.carCapacity;
  }

}

class Demo {

  public static void main(String args[]) {
    Car car = new Car("Ferrari", "F8", "100");
    System.out.println(car.getDetails());
  }

}

In this solution, the Car class has a default constructor and two parameterized constructors.

The default constructor is used to create an instance of the Car class with default values for its data members (carName, carModel, and carCapacity).

The parameterized constructors allow you to create a Car object with specific values passed as arguments. By using the parameterized constructors, you can provide values for the data members during object creation.

In the example, the first parameterized constructor takes two arguments (name and model) and sets the carName and carModel values accordingly.

The second parameterized constructor takes three arguments (name, model, and capacity). It calls the first parameterized constructor (using this(name, model)) to set the carName and carModel values, and then assigns the value of capacity to the carCapacity data member.

In the provided main method, a Car object is created using the second parameterized constructor with the arguments “Ferrari”, “F8”, and “100”. This sets the corresponding values for the carName, carModel, and carCapacity data members.

The getDetails method is used to retrieve the car details (carName, carModel, and carCapacity) as a formatted string.

When the main method is executed, it prints the details of the created Car object (“Ferrari, F8, 100”) using the getDetails method.
I hope it helps. Happy Learning :blush:

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