Binary Tree Test

package brackeen;
 
/*
 DEVELOPING GAME IN JAVA 
 
 Caracteristiques
 
 Editeur : NEW RIDERS 
 Auteur : BRACKEEN 
 Parution : 09 2003 
 Pages : 972 
 Isbn : 1-59273-005-1 
 Reliure : Paperback 
 Disponibilite : Disponible a la librairie 
 */
 
public class BinaryTreeTest {
 
    public static void main(String[] args) {
	new BinaryTreeTest().run();
    }
 
    static class Node {
	Node left;
 
	Node right;
 
	int value;
 
	public Node(int value) {
	    this.value = value;
	}
    }
 
    public void run() {
	// build the simple tree from chapter 11.
	Node root = new Node(5);
	System.out.println("Binary Tree Example");
	System.out.println("Building tree with root value " + root.value);
	insert(root, 1);
	insert(root, 8);
	insert(root, 6);
	insert(root, 3);
	insert(root, 9);
	System.out.println("Traversing tree in order");
	printInOrder(root);
	System.out.println("Traversing tree front-to-back from location 7");
	printFrontToBack(root, 7);
    }
 
    public void insert(Node node, int value) {
	if (value < node.value) {
	    if (node.left != null) {
		insert(node.left, value);
	    } else {
		System.out.println("  Inserted " + value + " to left of " + node.value);
		node.left = new Node(value);
	    }
	} else if (value > node.value) {
	    if (node.right != null) {
		insert(node.right, value);
	    } else {
		System.out.println("  Inserted " + value + " to right of " + node.value);
		node.right = new Node(value);
	    }
	}
    }
 
    public void printInOrder(Node node) {
	if (node != null) {
	    printInOrder(node.left);
	    System.out.println("  Traversed " + node.value);
	    printInOrder(node.right);
	}
    }
 
    /**
     * uses in-order traversal when the origin is less than the node's value
     * 
     * uses reverse-order traversal when the origin is greater than the node's order
     */
    public void printFrontToBack(Node node, int camera) {
	if (node == null)
	    return;
	if (node.value > camera) {
	    // print in order
	    printFrontToBack(node.left, camera);
	    System.out.println("  Traversed " + node.value);
	    printFrontToBack(node.right, camera);
	} else if (node.value < camera) {
	    // print reverse order
	    printFrontToBack(node.right, camera);
	    System.out.println("  Traversed " + node.value);
	    printFrontToBack(node.left, camera);
	} else {
	    // order doesn't matter
	    printFrontToBack(node.left, camera);
	    printFrontToBack(node.right, camera);
	}
    }
 
}