Sobreescribir un método; @override, protected y super

En este tutorial vamos a continuar con el ejemplo del hotel de perros que hemos estado haciendo en los anteriores tutoriales, para explicar las palabras "override, protected y super".

Vamos a utilizar la misma clase main (ahora llamada Tutorial14):

package com.edu4java.tutorial14;

public class Tutorial14 {

	public static void main(String[] args) {
		Dog2[] dogs = insertDog();
		printDogsOnConsole(dogs);
		feed(dogs);
		System.out.println("After eating------------");
		printDogsOnConsole(dogs);

	}

	private static void feed(Dog2[] dogs) {
		for (int i = 0; i < dogs.length; i++) {
			double weightBeforefeeding = dogs[i].getWeight();
			dogs[i].setWeight(weightBeforefeeding + dogs[i].getPortion());
		}

	}

	private static void printDogsOnConsole(Dog2[] dogs) {
		for (int i = 0; i < dogs.length; i++) {
			dogs[i].printToConsole();
		}

	}

	private static Dog2[] insertDog() {

		Dog2[] dogs = new Dog2[4];

		// list of Dogs
		String[] names = { "Coco", "Sultan", "Boby", "Drak" };
		String[] colours = { "brown", "black", "white", "blue" };
		double[] weight = { 1.5, 75, 3.5, 45.1 };
		double[] portion = { 0.2, 1, 0.2, 0.8 };

		for (int i = 0; i < dogs.length; i++) {
			Dog2 dog = new Dog2();
			dog.setName(names[i]);
			dog.setColour(colours[i]);
			dog.setWeight(weight[i]);
			dog.setPortion(portion[i]);
			dogs[i] = dog;

		}
		return dogs;
	}

}

En la clase Dog, introduciremos el concepto de protected, haciendo que la variable colour sea accesible desde la clase hija Dog2.

package com.edu4java.tutorial14;

/**
 * A class is a mould from which we can create objects or instances
 * An object is an instance of a class
 * 
 * JavaBeans are reusable software components for Java
 * that can be manipulated visually in a builder tool.
 */
public class Dog {
	// instance variables

	private String name;
	private double weight;
	protected String colour;

	
	public String getName() {
		return name;
	}


	public void setName(String name) {
		this.name = name;
	}
	

	public double getWeight() {
		return weight;
	}


	public void setWeight(double weight) {
		this.weight = weight;
	}


	public String getColour() {
		return colour;
	}


	public void setColour(String colour) {
		this.colour = colour;
	}


	public void printToConsole() {
		System.out.print(" name: " + getName());
		System.out.print(" colour: " + this.colour);
		System.out.println(" weight: " + this.weight);

	}
}

En la clase Dog2 conseguimos imprimir la variable "portion" sin tener que modificar la clase Dog, sobreescribiendo el método printOnConsole.

package com.edu4java.tutorial14;

public class Dog2 extends Dog {
	private double portion;

	public double getPortion() {
		return portion;
	}

	public void setPortion(double portion) {
		this.portion = portion;
	}
	@Override
	public void printToConsole() {
		super.printToConsole();
		System.out.println(" portion: " + this.portion);
	}
}

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