Inheritance

// File:            Main.kt
// Programmer:      Engineer Nolverto Urias Obeso
// Creation Date:   06/18/2023
// Email:           nolvertou@gmail.com
// Description:     Learn how to use the inheritance

fun main() {
    buildTowerTank()
}

fun buildTowerTank() {
    val smallAquarium = Aquarium()
    println("Small Aquarium: ${smallAquarium.volume} liters (Max Capacity) with " +
            "Length: ${smallAquarium.length} cm, " +
            "Width: ${smallAquarium.width} cm, " +
            "Height: ${smallAquarium.height} cm,  " +
            "Water: ${smallAquarium.water} liters")

    val towerTank = TowerTank()
    println("TowerTank: ${towerTank.volume} liters (Max Capacity) with " +
            "Length: ${towerTank.length} cm, " +
            "Width: ${towerTank.width} cm, " +
            "Height: ${towerTank.height} cm, " +
            "Water: ${towerTank.water} liters")
}

Parent Class:

// To inherit from a class you have to change the class to open, by default classes are not subclassible and we have to
// explicitly allow it using open keyword on the left hand of class keyword
open class Aquarium(var length: Int = 100, var width: Int = 20, var height: Int = 40) { // Primary Constructor
    // We must add the open keyword to override the attribute value using inheritance
    open var volume: Int
        get() = width * height * length / 1000   // It calculates the volume
        set(value){ height = (value * 1000) / (width * length)} // It sets the height giving the volume value

    // We must add the open keyword to override the attribute value using inheritance
    open var water = volume * 0.9    // It's used the 90% of the tank volume


    // The arguments have to match exactly the with one of the available constructors
    // If you declare a secondary constructor it must containt a call to the primary constructor by using this()
    constructor(numberOfFish:Int): this(){ // Secondary constructor
        val water:Int = numberOfFish * 2000 //cm3
        val tank: Double = water + water * 0.1
        height = (tank/(length*width)).toInt()  // Calculates the height depending of number of fish
    }

}

Child Class:

import kotlin.math.PI

class TowerTank() : Aquarium() {
    // If we want to change the inherited attributes we must use override keyword and add open keyword to the parent attribute
    override var water = volume *0.8

    override var volume: Int
        get() = (width * height * length / (1000 * PI)).toInt()
        set(value) {height = (value * 1000) / (width * length)}
}