/*
 * File: ZHBinarySearchTree.java
 */

package zhstructures;

import java.util.Iterator;

/**
 * Interface for classes representing a binary search tree.
 * 
 * @author J. Andrew Holey
 * @version April 18, 2008
 *
 * @param <ElementType> the type of data stored in the nodes of this tree
 */
public interface ZHBinarySearchTree<ElementType extends Comparable<ElementType>>
		extends ZHCollection<ElementType> {

	/* (non-Javadoc)
	 * @see zhstructures.ZHCollection#isEmpty()
	 */
	public boolean isEmpty();
	
	/* (non-Javadoc)
	 * @see zhstructures.ZHCollection#contains(java.lang.Object)
	 */
	public boolean contains(ElementType element);
	
	/* (non-Javadoc)
	 * @see java.lang.Iterable#iterator()
	 */
	public Iterator<ElementType> iterator();
	
	/**
	 * Adds the specified element to this tree if not already present and returns
	 * true if the tree was modified as a result of this operation, otherwise false.
	 * 
	 * @param element the element to be removed
	 * @return true if this tree was modified as a result of this operation
	 */
	public boolean add(ElementType element);
	
	/**
	 * Removes the specified element from this tree if present and returns true
	 * if the tree was modified as a result of this operation, otherwise false.
	 * 
	 * @param element
	 * @return true if the element was previously present
	 */
	public boolean remove(ElementType element);

}