JAVA红黑树实现(2)

转自http://blog.sina.com.cn/s/blog_537bb50a010000ir.html

续一
====红黑树操作的实现，插入、删除、查找 （一）====

/*
 * @(#)Rbtree.java
 *
 * Title: This class is to define the RBtree.
 * Description: This file is the assignment of Algorithms.
 * @copyright (c) OpenSource
 * @author Bobby Yang
 * @tester Bobby Yang
 * @version 1.00
 * @time 2005.11.04
 */

package rbtree;

public class Rbtree {
   
    private Node root;
   
    private static Node nil = new Node();
       
    private static void initNil(){
        nil.iData = 0;
        nil.color = true;
        nil.leftChild = null;
        nil.rightChild = null;
    }
   
    private void setRoot(Node node){
        this.root = node;
    }
   
    private void preOrder(Node root){
        if(root != null) System.out.print("(" + root.iData + root.getColor() + ",");
        if(root.leftChild == nil) System.out.print("NIL,");
        else {
           preOrder(root.leftChild);
           System.out.print(",");
        }
        if(root.rightChild == nil) System.out.print("NIL)");
        else{
           preOrder(root.rightChild);
           System.out.print(")");
        }
    }

    private void insert(Node newNode){
        if(root == null){                       // no node in root
            root = newNode;
            root.parent = nil;
            }
        else                                 // root occupied
            {
            Node current = root;             // start at root
            Node parent;
            while(true){                     // (exits internally)
                parent = current;
                if(newNode.iData < current.iData)        // go left
                    {
                    current = current.leftChild;
                    if(current == nil){        // if end of the line,
                        // insert on left
                        parent.leftChild = newNode;
                        newNode.parent = parent;
                        return;
                        }
                     }                          // end if go left
                 else{                          // or go right
                     current = current.rightChild;
                     if(current == nil){       // if end of the line
                         // insert on right
                         parent.rightChild = newNode;
                         newNode.parent = parent;
                         return;
                         }
                     }                          // end else go right
            }                                   // end while
        }                                       // end else not root
    }