/* This is wrapper class...
 Objective would be to push more functionality into this Class to enforce consistent definition
 */
public abstract class Generics {
	public final String masterType = "Generic";
	private String type;	// extender should define their data type

	// generic enumerated interface
	public interface KeyTypes {
		String name();
	}
	protected abstract KeyTypes getKey();  	// this method helps force usage of KeyTypes

	// getter
	public String getMasterType() {
		return masterType;
	}

	// getter
	public String getType() {
		return type;
	}

	// setter
	public void setType(String type) {
		this.type = type;
	}
	
	// this method is used to establish key order
	public abstract String toString();

	// static print method used by extended classes
	public static void print(Generics[] objs) {
		// print 'Object' properties
		System.out.println(objs.getClass() + " " + objs.length);

		// print 'Generics' properties
		if (objs.length > 0) {
			Generics obj = objs[0];	// Look at properties of 1st element
			System.out.println(
					obj.getMasterType() + ": " + 
					obj.getType() +
					" listed by " +
					obj.getKey());
		}

		// print "Generics: Objects'
		for(Object o : objs)	// observe that type is Opaque
			System.out.println(o);

		System.out.println();
	}
}

public class Car extends Generics {
	// Class data
	public static KeyTypes key = KeyType.title;  // static initializer
	public static void setOrder(KeyTypes key) { Car.key = key; }
	public enum KeyType implements KeyTypes {title, name, year, model}

	// Instance data
	private final String name;
	private final int year;
	private final String model;

	/* constructor
	 *
	 */
	public Car(String name, int year, String model)
	{
		super.setType("Car");
		this.name = name;
		this.year = year;
		this.model = model;
	}

	/* 'Generics' requires getKey to help enforce KeyTypes usage */
	@Override
	protected KeyTypes getKey() { return Car.key; }
	
	/* 'Generics' requires toString override
	 * toString provides data based off of Static Key setting
	 */
	@Override
	public String toString()
	{
		String output="";
		if (KeyType.name.equals(this.getKey())) {
			output += this.name;
		} else if (KeyType.year.equals(this.getKey())) {
			output += "00" + this.year;
			output = output.substring(output.length() - 2);
		} else if (KeyType.model.equals(this.getKey())) {
			output += this.model;
		} else {
			output += super.getType() + ": " + this.name + ", " + this.model + ", " + this.year;
		}
		return output;
		
	}

	// Test data initializer
	public static Car[] cars() {
		return new Car[]{
			new Car("Honda", 2016, "Odyssey"),
			new Car("Toyota", 2012, "Corolla"),
			new Car("Lexus", 2019, "UX"),
			new Car("Acura", 2016, "Integra"),
			new Car("Kia", 2023, "Forte"),
			new Car("Lamborghini", 2022, "Huracan EVO")
		};
	}
	
	/* main to test Animal class
	 * 
	 */
	public static void main(String[] args)
	{
		// Inheritance Hierarchy
		Car[] objs = cars();

		// print with title
		Car.setOrder(KeyType.title);
		Car.print(objs);

		// print name only
		Car.setOrder(KeyType.name);
		Car.print(objs);
	}

}
Car.main(null);

public class Sport extends Generics {
	// Class data
	public static KeyTypes key = KeyType.title;  // static initializer
	public static void setOrder(KeyTypes key) {Sport.key = key;}
	public enum KeyType implements KeyTypes {title, name, numPlayers}

	// Instance data
	private final String name;
	private final int numPlayers;

	// Constructor
	Sport(String name, int numPlayers)
	{
		this.setType("Sport");
		this.name = name;
		this.numPlayers = numPlayers;
	}

	/* 'Generics' requires getKey to help enforce KeyTypes usage */
	@Override
	protected KeyTypes getKey() { return Sport.key; }

	/* 'Generics' requires toString override
	 * toString provides data based off of Static Key setting
	 */
	@Override
	public String toString() {		
		String output="";
		if (KeyType.name.equals(this.getKey())) {
			output += this.name;
		} else if (KeyType.numPlayers.equals(this.getKey())) {
			output += "00" + this.numPlayers;
			output = output.substring(output.length() - 2);
		} else {
			output = super.getType() + ": " + this.name + ", " + this.numPlayers;
		}
		return output;
	}

	// Test data initializer
	public static Sport[] sports() {
		return new Sport[]{
				new Sport("Soccer", 22),
			    new Sport("Basketball", 10),
			    new Sport("Volleyball", 12),
			    new Sport("Tennis", 2),
			    new Sport("Football", 22)
		};
	}
	
	public static void main(String[] args)
	{
		// Inheritance Hierarchy
		Sport[] objs = sports();

		// print with title
		Sport.setOrder(KeyType.title);
		Sport.print(objs);

		// print flavor only
		Sport.setOrder(KeyType.name);
		Sport.print(objs);
		
		// print numPlayers only
		Sport.setOrder(KeyType.numPlayers);
		Sport.print(objs);
	}
	
}
Sport.main(null);

/**
 *  Implementation of a Double Linked List;  forward and backward links point to adjacent Nodes.
 *
 */

 public class LinkedList<T>
 {
     private T data;
     private LinkedList<T> prevNode, nextNode;
 
     /**
      *  Constructs a new element
      *
      * @param  data, data of object
      * @param  node, previous node
      */
     public LinkedList(T data, LinkedList<T> node)
     {
         this.setData(data);
         this.setPrevNode(node);
         this.setNextNode(null);
     }
 
     /**
      *  Clone an object,
      *
      * @param  node  object to clone
      */
     public LinkedList(LinkedList<T> node)
     {
         this.setData(node.data);
         this.setPrevNode(node.prevNode);
         this.setNextNode(node.nextNode);
     }
 
     /**
      *  Setter for T data in DoubleLinkedNode object
      *
      * @param  data, update data of object
      */
     public void setData(T data)
     {
         this.data = data;
     }
 
     /**
      *  Returns T data for this element
      *
      * @return  data associated with object
      */
     public T getData()
     {
         return this.data;
     }
 
     /**
      *  Setter for prevNode in DoubleLinkedNode object
      *
      * @param node, prevNode to current Object
      */
     public void setPrevNode(LinkedList<T> node)
     {
         this.prevNode = node;
     }
 
     /**
      *  Setter for nextNode in DoubleLinkedNode object
      *
      * @param node, nextNode to current Object
      */
     public void setNextNode(LinkedList<T> node)
     {
         this.nextNode = node;
     }
 
 
     /**
      *  Returns reference to previous object in list
      *
      * @return  the previous object in the list
      */
     public LinkedList<T> getPrevious()
     {
         return this.prevNode;
     }
 
     /**
      *  Returns reference to next object in list
      *
      * @return  the next object in the list
      */
     public LinkedList<T> getNext()
     {
         return this.nextNode;
     }
 
 }

 import java.util.Iterator;

/**
 * Queue Iterator
 *
 * 1. "has a" current reference in Queue
 * 2. supports iterable required methods for next that returns a generic T Object
 */
class QueueIterator<T> implements Iterator<T> {
    LinkedList<T> current;  // current element in iteration

    // QueueIterator is pointed to the head of the list for iteration
    public QueueIterator(LinkedList<T> head) {
        current = head;
    }

    // hasNext informs if next element exists
    public boolean hasNext() {
        return current != null;
    }

    // next returns data object and advances to next position in queue
    public T next() {
        T data = current.getData();
        current = current.getNext();
        return data;
    }
}

/**
 * Queue: custom implementation
 * @author     John Mortensen
 *
 * 1. Uses custom LinkedList of Generic type T
 * 2. Implements Iterable
 * 3. "has a" LinkedList for head and tail
 */
public class Queue<T> implements Iterable<T> {
    LinkedList<T> head = null, tail = null;

    /**
     *  Add a new object at the end of the Queue,
     *
     * @param  data,  is the data to be inserted in the Queue.
     */
    public void add(T data) {
        // add new object to end of Queue
        LinkedList<T> tail = new LinkedList<>(data, null);

        if (this.head == null)  // initial condition
            this.head = this.tail = tail;
        else {  // nodes in queue
            this.tail.setNextNode(tail); // current tail points to new tail
            this.tail = tail;  // update tail
        }
    }

    /**
     *  Returns the data of head.
     *
     * @return  data, the dequeued data
     */
    public T delete() {
        T data = this.peek();
        if (this.tail != null) { // initial condition
            this.head = this.head.getNext(); // current tail points to new tail
            if (this.head != null) {
                this.head.setPrevNode(tail);
            }
        }
        return data;
    }

    /**
     *  Returns the data of head.
     *
     * @return  this.head.getData(), the head data in Queue.
     */
    public T peek() {
        return this.head.getData();
    }

    /**
     *  Returns the head object.
     *
     * @return  this.head, the head object in Queue.
     */
    public LinkedList<T> getHead() {
        return this.head;
    }

    /**
     *  Returns the tail object.
     *
     * @return  this.tail, the last object in Queue
     */
    public LinkedList<T> getTail() {
        return this.tail;
    }

    /**
     *  Returns the iterator object.
     *
     * @return  this, instance of object
     */
    public Iterator<T> iterator() {
        return new QueueIterator<>(this.head);
    }
}

/**
 * Queue Manager
 * 1. "has a" Queue
 * 2. support management of Queue tasks (aka: titling, adding a list, printing)
 */
class QueueManager<T> {
    // queue data
    private final String name; // name of queue
    private int count = 0; // number of objects in queue
    public final Queue<T> queue = new Queue<>(); // queue object

    /**
     *  Queue constructor
     *  Title with empty queue
     */
    public QueueManager(String name) {
        this.name = name;
    }

    /**
     *  Queue constructor
     *  Title with series of Arrays of Objects
     */
    public QueueManager(String name, T[]... seriesOfObjects) {
        this.name = name;
        this.addList(seriesOfObjects);
    }

    /**
     * Add a list of objects to queue
     */
    public void addList(T[]... seriesOfObjects) {  //accepts multiple generic T lists
        for (T[] objects: seriesOfObjects)
            for (T data : objects) {
                this.queue.add(data);
                this.count++;
            }
    }

    /**
     * Print any array objects from queue
     */
    public void printQueue() {
        System.out.println(this.name + " count: " + count);
        System.out.print(this.name + " data: ");
        for (T data : queue)
            System.out.print(data + " ");
        System.out.println();
    }
}

/**
 * Driver Class
 * Tests queue with string, integers, and mixes of Classes and types
 */
class QueueTester {
    public static void main(String[] args)
    {

        // Create iterable Queue of NCS Generics
        Car.setOrder(Car.KeyType.name);
        Sport.setOrder(Sport.KeyType.name);
        // Illustrates use of a series of repeating arguments
        QueueManager qGenerics = new QueueManager("My Generics",
                Car.cars(),
                Sport.sports()
        );
        qGenerics.printQueue();

        // Create iterable Queue of Mixed types of data
        QueueManager qMix = new QueueManager("Mixed");
        qMix.queue.add("Start");
        qMix.addList(
                Car.cars(),
                Sport.sports()
        );
        qMix.queue.add("End");
        qMix.printQueue();
    }
}
QueueTester.main(null);
class [LREPL.$JShell$13$Car; 6
Generic: Car listed by title
Car: Honda, Odyssey, 2016
Car: Toyota, Corolla, 2012
Car: Lexus, UX, 2019
Car: Acura, Integra, 2016
Car: Kia, Forte, 2023
Car: Lamborghini, Huracan EVO, 2022

class [LREPL.$JShell$13$Car; 6
Generic: Car listed by name
Honda
Toyota
Lexus
Acura
Kia
Lamborghini

class [LREPL.$JShell$15$Sport; 5
Generic: Sport listed by title
Sport: Soccer, 22
Sport: Basketball, 10
Sport: Volleyball, 12
Sport: Tennis, 2
Sport: Football, 22

class [LREPL.$JShell$15$Sport; 5
Generic: Sport listed by name
Soccer
Basketball
Volleyball
Tennis
Football

class [LREPL.$JShell$15$Sport; 5
Generic: Sport listed by numPlayers
22
10
12
02
22

My Generics count: 11
My Generics data: Honda Toyota Lexus Acura Kia Lamborghini Soccer Basketball Volleyball Tennis Football 
Mixed count: 11
Mixed data: Start Honda Toyota Lexus Acura Kia Lamborghini Soccer Basketball Volleyball Tennis Football End