ID3/src/com/AI/NaryTree.java

package com.AI;
import com.DBpackage.MyDatabase;

import java.util.ArrayList;

class Node
{
	private String attributeName;
	private ArrayList<Value> valuesList;

	class Value
	{
		private String value;
		private Node next;

		public Value()
		{
			next = null;
		}

		String getValue() {
			return value;
		}

		void setValue(String value) {
			this.value = value;
		}

		Node getNext() {
			return next;
		}

		void setNext(Node next) {
			this.next = next;
		}

	}

	public Node()
	{
		valuesList = new ArrayList<>();
	}
	public Node(String attributeName)
	{
		this.setAttributeName(attributeName);
		valuesList = new ArrayList<>();
	}
	public String getAttributeName()
	{
		return attributeName;
	}

	public void setAttributeName(String attributeName)
	{
		this.attributeName = attributeName;
	}

	public ArrayList<Value> getValuesList() {
		return valuesList;
	}

	public void setValuesList(ArrayList<Value> valuesList) {
		this.valuesList = valuesList;
	}

	void setVal(String value, Node obj)
	{

		Value valueObj = new Value();
		valueObj.setValue(value);
		valueObj.setNext(obj);
		//obj.getValuesList().get(0).setPrevious(this);
		//if(obj.getPrevious().getValuesList().get(0).isVisited() == true);
		valuesList.add(valueObj);
	}

}

class NaryTree
{
	private Node head;

	NaryTree()
	{
		head = null;
	}

	public Node getHead() {
		return head;
	}

	public void setHead(Node head) {
		this.head = head;
	}


	//////////////////////////////////////////////////////////////////////////////////
	/*Node createNode(Node h, Node parent, String edgeName, Node child) {
		if (head == null)
		{
			System.out.println("Initializing head node");
//			h = new Node(parentName);
//			this.setHead(h);
//			System.out.println("Head: " + h.getAttributeName());
//			return h;
			head = parent;
			return head;
		}
		else
		{
			createLink(parent, child, edgeName);
			return child;
		}
	}*/
	Node createNode(Node h, Node parent, String edgeName, Node child) {
		if (head == null)
		{
			System.out.println("Initializing head node");
//			h = new Node(parentName);
//			this.setHead(h);
//			System.out.println("Head: " + h.getAttributeName());
//			return h;
			head = parent;
			return head;
		}
		else
		{
			createLink(parent, child, edgeName);
			return child;
		}
	}

	private void createLink(Node parent, Node child, String value)
	{
//		System.out.println("Edge: " + value + " Child: " + child.getAttributeName() );
		parent.setVal(value, child);
	}
	//////////////////////////////////////////////////////////////////////////////////
	private void traverse(Node node)
	{
		if(node == null)
		{
			System.out.println();
			return;
		}
		System.out.print(" " + node.getAttributeName() + " ");
		if(node.getAttributeName().equalsIgnoreCase("Yes") ||
				node.getAttributeName().equalsIgnoreCase("No"))
			System.out.println();
		if(node.getValuesList() == null) {
			System.out.print(node.getAttributeName());
			return;
		}

		for(Node.Value v: node.getValuesList())
		{
			System.out.print(" " + v.getValue());
			traverse(v.getNext());
		}

	}
	void displayTree()
	{
		System.out.println("Displaying tree(pre-order):");
		System.out.println("------------------");
		if(head!=null) {
			traverse(head);
		}
		else
		{
			System.out.println("Head node not created/initialized");
		}
		System.out.println();
		System.out.print("------------------");
		System.out.println();
	}
	//////////////////////////////////////////////////////////////////////////////////////////////////////////

	private void traverseDBTest(Node node, MyDatabase myDatabase)
	{
		if(node == null)
		{
			System.out.println();
			return;
		}

		//System.out.print(" " + node.getAttributeName());
		if(node.getValuesList() == null) {
//			System.out.print(node.getAttributeName());
			return;
		}
		for(Node.Value value : node.getValuesList())
		{
//			System.out.print(" " + sn.getValue());
			if(value.getNext().getAttributeName() == null)
				System.out.println("null");
			else {
				myDatabase.insertTree(node.getAttributeName(), value.getValue(), value.getNext().getAttributeName());
				System.out.println("Parent: " + node.getAttributeName()
						+ " Edge: " + value.getValue()
						+ " Child: " + value.getNext().getAttributeName());
			}
			traverseDBTest(value.getNext(),myDatabase);
		}
		//System.out.println("Node named" + nodeName + "does not exist in the tree");

	}

	void dbTest(MyDatabase myDatabase)
	{
		if(head!=null) {
			traverseDBTest(head, myDatabase);
		}
		else
		{
			System.out.println("Head node not created/initialized");
		}
		System.out.println();
	}
	//////////////////////////////////////////////////////////////////////////////////////////////////////////
}