Java Inheritance Basics - thelastmile/FreeCodeCamp GitHub Wiki

Java Inheritance

So great you have successfully created a Car class. But, wait, aren't Tesla cars supposed to be electric variants? I want an Electric car class, but it also should have the properties of the original Car class.

Solution : Inheritance. Java provides a neat way to "inherit" parent properties :

public class Car {

    private String name;
    private String manufacturerName;

    public Car(String name, String man) {
        this.name = name;
        this.manufacturerName = man;
    }
    // Getter method
    public String getName() {
        return name;
    }
    // Getter method
    public String getManufacturerName() {
        return manufacturerName;
    }
}

public class ElectricCar extends Car {

    public ElectricCar(String name, String man) {
        super(name, man);
    }

    public void charge() {
     System.out.println("Charging ...");
    }
}

ElectricCar modelS = new ElectricCar("Model S","Tesla");
// prints Tesla
System.out.println(modelS.getManufacturerName());
// prints Charging ...
modelS.charge();

:rocket: Run Code

See here that the class ElecticCar inherits or extends the public methods from Car class, as well as has its own methods and properties. Cool way to pass on information!

Also notice the usage of super keyword here. Since our Car class had a constructor, so we have to initialize that constructor from the child class as well. We do that using the super keyword. Read more about Inheritance here.

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