Source for file TreeNode.interface.php

<?php
 
/** 
 * This is the building piece of the Tree data structure used for the backbone of the
 * hierarchy.
 *
 * @package harmoni.osid_v2.hierarchy.tree
 * 
 * @copyright Copyright &copy; 2005, Middlebury College
 * @license http://www.gnu.org/copyleft/gpl.html GNU General Public License (GPL)
 *
 * @version $Id: TreeNode.interface.php,v 1.7 2007/09/04 20:25:42 adamfranco Exp $
 * @since Created: 8/30/2003
 */
class TreeNodeInterface {
 
    
    /**
     * Adds a new child for this node.
     * @access public
     * @param ref object child The child node to add.
     * @return void 
     */
    function addChild($child) {
        die ("Method <b>".__FUNCTION__."()</b> declared in interface<b> ".__CLASS__."</b> has not been overloaded in a child class.");
    }
    
    
    /**
     * Detaches the child from this node. The child remains in the hierarchy.
     * @access public
     * @param ref object child The child node to detach.
     * @return void 
     ***/
    function detachChild($child) {
        die ("Method <b>".__FUNCTION__."()</b> declared in interface<b> ".__CLASS__."</b> has not been overloaded in a child class.");
    }
    
    
    /**
     * Returns the parent node of this node.
     * @access public
     * @return ref array The parent nodes of this node.
     */
    function getParents() {
        die ("Method <b>".__FUNCTION__."()</b> declared in interface<b> ".__CLASS__."</b> has not been overloaded in a child class.");
    }
    
 
    /**
     * Returns the number of parents for this node.
     * @access public
     * @return integer The number of parents for this node.
     */
    function getParentsCount() {
        die ("Method <b>".__FUNCTION__."()</b> declared in interface<b> ".__CLASS__."</b> has not been overloaded in a child class.");
    }
 
 
    /**
     * Determines if this node has any parents.
     * @access public
     * @return boolean <code>true</code> if this node has at least one parent;
     *  <code>false</code>, otherwise.
     */
    function hasParents() {
        die ("Method <b>".__FUNCTION__."()</b> declared in interface<b> ".__CLASS__."</b> has not been overloaded in a child class.");
    }
 
 
    /**
     * Returns the children of this node in the order they were added.
     * @access public
     * @return ref array An array of the children nodes of this node.
     */
    function getChildren() {
        die ("Method <b>".__FUNCTION__."()</b> declared in interface<b> ".__CLASS__."</b> has not been overloaded in a child class.");
    }
    
    
    /**
     * Returns the number of children for this node.
     * @access public
     * @return integer The number of children for this node.
     */
    function getChildrenCount() {
        die ("Method <b>".__FUNCTION__."()</b> declared in interface<b> ".__CLASS__."</b> has not been overloaded in a child class.");
    }
    
    
    /**
     * Determines if this node has any children.
     * @access public
     * @return boolean <code>true</code> if this node has at least one child;
     *  <code>false</code>, otherwise.
     */
    function hasChildren() {
        die ("Method <b>".__FUNCTION__."()</b> declared in interface<b> ".__CLASS__."</b> has not been overloaded in a child class.");
    }
    
    
    /**
     * Checks if the given node is a child of this node.
     * @access public
     * @param ref object node The child node to check.
     * @return boolean <code>true</code> if <code>$node</code> is a child of this node.
     ***/
    function isChild($node) {
        die ("Method <b>".__FUNCTION__."()</b> declared in interface<b> ".__CLASS__."</b> has not been overloaded in a child class.");
    }
    
    /**
     * Checks if the given node is a parent of this node.
     * @access public
     * @param ref object node The child node to check.
     * @return boolean <code>true</code> if <code>$node</code> is a parent of this node.
     ***/
    function isParent($node) {
        die ("Method <b>".__FUNCTION__."()</b> declared in interface<b> ".__CLASS__."</b> has not been overloaded in a child class.");
    }
    
    /**
     * Returns the id of this node.
     * @access public
     * @return string The id of this node.
     */
    function getId() {
        die ("Method <b>".__FUNCTION__."()</b> declared in interface<b> ".__CLASS__."</b> has not been overloaded in a child class.");
    }
    
}
 
?>