PathNode.java

package Q17_22_Word_Transformer;

import java.util.LinkedList;

public class PathNode {
	private String word = null;
	private PathNode previousNode = null;
	public PathNode(String word, PathNode previous) {
		this.word = word;
		previousNode = previous;
	}
	
	public String getWord() {
		return word;
	}
	
	/* Traverse path and return linked list of nodes. */
	public LinkedList<String> collapse(boolean startsWithRoot) {
		LinkedList<String> path = new LinkedList<String>();
		PathNode node = this;
		while (node != null) {
			if (startsWithRoot) {
				path.addLast(node.word);
			} else {
				path.addFirst(node.word);
			}
			node = node.previousNode;
		}
		return path;
	}
}