public class TreeNode<T> {
  public enum Color {red, black}
  
  private T item;
  private TreeNode<T> leftChild;
  private TreeNode<T> rightChild;
  private TreeNode<T> parent;
  private Color color;
  
  public TreeNode(T newItem) {
    // Initializes tree node with item and no children.
    item = newItem;
    leftChild  = null;
    rightChild = null;
    parent = null;
    color = Color.red;
  }  // end constructor
  
  public TreeNode(T newItem, 
      TreeNode<T> left, TreeNode<T> right,
      Color col) {
    // Initializes tree node with item and
    // the left and right children references.
    item = newItem;
    leftChild  = left;
    rightChild = right;
    parent = null;
    color = col;
  }  // end constructor
  
  public T getItem() {
    // Returns the item field.
    return item;
  }  // end getItem
  
  public void setItem(T newItem) {
    // Sets the item field to the new value newItem.
    item  = newItem;
  }  // end setItem
  
  public TreeNode<T> getLeft() {
    // Returns the reference to the left child.
    return leftChild;
  }  // end getLeft
  
  public void setLeft(TreeNode<T> left) {
    // Sets the left child reference to left.
    leftChild  = left;
  }  // end setLeft
  
  public TreeNode<T> getRight() {
    // Returns the reference to the right child.
    return rightChild;
  }  // end getRight
  
  public void setRight(TreeNode<T> right) {
    // Sets the right child reference to right.
    rightChild  = right;
  }  // end setRight
  
  public TreeNode<T> getParent() {
    // Returns the reference to the right child.
    return parent;
  }  // end getRight
  
  public void setParent(TreeNode<T> newParent) {
    // Sets the right child reference to right.
    parent  = newParent;
  }  // end setRight
  
  public Color getColor() {
    // Returns the color of the node
    return color;
  }
  
  public void setColor(Color newColor) {
    // Sets the color of the node
    color = newColor;
  }
}  // end TreeNode