package TreePackage;
/**
   A class that represents nodes in a binary tree.
   
   @author Frank M. Carrano
   @author Timothy M. Henry
   @version 5.0
*/
class BinaryNode<T>
{
   private T             data;
   private BinaryNode<T> leftChild;  // Reference to left child
   private BinaryNode<T> rightChild; // Reference to right child

   public BinaryNode()
   {
      this(null); // Call next constructor
   } // end default constructor

   public BinaryNode(T dataPortion)
   {
      this(dataPortion, null, null); // Call next constructor
   } // end constructor

   public BinaryNode(T dataPortion, BinaryNode<T> newLeftChild,
                                    BinaryNode<T> newRightChild)
   {
      data = dataPortion;
      leftChild = newLeftChild;
      rightChild = newRightChild;
   } // end constructor

   /** Retrieves the data portion of this node.
       @return  The object in the data portion of the node. */
   public T getData()
   {
      return data;
   } // end getData

   /** Sets the data portion of this node.
       @param newData  The data object. */
   public void setData(T newData)
   {
      data = newData;
   } // end setData

   /** Retrieves the left child of this node.
       @return  A reference to this node's left child. */
   public BinaryNode<T> getLeftChild()
   {
      return leftChild;
   } // end getLeftChild

   /** Sets this node’s left child to a given node.
       @param newLeftChild  A node that will be the left child. */
   public void setLeftChild(BinaryNode<T> newLeftChild)
   {
      leftChild = newLeftChild;
   } // end setLeftChild

   /** Detects whether this node has a left child.
       @return  True if the node has a left child. */
   public boolean hasLeftChild()
   {
      return leftChild != null;
   } // end hasLeftChild

/*   Implementations of getRightChild, setRightChild, and hasRightChild
     are here and are analogous to their left-child counterparts. */
   
   /** Detects whether this node is a leaf.
    @return  True if the node is a leaf. */
   public boolean isLeaf()
   {
      return (leftChild == null) && (rightChild == null);
   } // end isLeaf
   
   /** Counts the nodes in the subtree rooted at this node.
       @return  The number of nodes in the subtree rooted at this node. */
   public int getNumberOfNodes()
   {
      // < See Segment 25.10. >
   } // end getNumberOfNodes
   
   /** Computes the height of the subtree rooted at this node.
       @return  The height of the subtree rooted at this node. */
   public int getHeight()
   {
      // < See Segment 25.10. >
   } // end getHeight

   /** Copies the subtree rooted at this node.
       @return  The root of a copy of the subtree rooted at this node. */
   public BinaryNode<T> copy()
   {
      // < See Segment 25.5. >
   } // end copy
} // end BinaryNode