如何在不重复节点的情况下删除BST中的节点？

Question

我的代码如下。我在删除方法方面遇到问题，我无法删除二进制搜索树中的节点并替换它而不创建两个替换节点...我该如何解决这个问题？

public class BSTMain {
public static void DeleteValue(int num, BSTNode root){
    BSTNode cursor = root;
    while(true){ //move cursor
        while(cursor.getLeft()!=null && num<cursor.getData()){
            //move cursor
            cursor = cursor.getLeft();
        }
        while(cursor.getRight()!=null && num>cursor.getData()){
            //move cursor
            cursor = cursor.getRight();
        }
        if(cursor.getData() == num || (cursor.getLeft()==null && num<cursor.getData()) || (cursor.getRight()==null && num>cursor.getData())) //check for placing cases 
            break; //time to delete node in the tree
    }
    if(cursor.getData()==num){//delete node
        if(cursor.getLeft()!=null){ //if left exists
            BSTNode cursor2 = cursor.getLeft();
            while(cursor2.getRight()!=null){ //get rightmost of left to replace
                cursor2 = cursor2.getRight();
            }
            cursor.setData(cursor2.getData()); //replace cursor
            if(cursor2.getLeft()!=null)
                cursor2.getLeft().root = cursor2.root; //Replace cursor2
            cursor2.root.setRight(cursor2.getLeft());
        } else if(cursor.getRight()!=null){ //if no left but right
            BSTNode cursor2 = cursor.getRight(); 
            while(cursor2.getLeft()!=null){ //get leftmost of right
                cursor2 = cursor2.getLeft();
            }
            cursor.setData(cursor2.getData()); //replace cursor
            if(cursor2.getRight()!=null)
                cursor2.getRight().root = cursor2.root; //Replace cursor2
            cursor2.root.setLeft(cursor2.getRight());
        } else {
            System.out.println("Node " + num + " does not exist!");
        }
    }
    else System.out.println(num + " does not exist in Binary Search Tree!");
}
}

一些输出：
按顺序：19 20 21 22 23 23 45
指挥：D 19
删除后：20 20 21 22 23 23 45
命令：D 20
删除后：20 20 21 22 23 23 45
命令：D 21
删除后：20 20 22 23 23 45
命令：D 22
删除后：20 20 20 20 23 23 45
命令：D 23
删除后：20 20 20 20 23 23 20 20 20 20 45
命令：D 45
删除后：20 20 20 23 23 20 20 20 20
命令：D 20
删除后：20 20 20 23 23 20 20 20
命令：D 20
删除后：20 20 20 23 23 20 20
命令：D 20
删除后：20 20 20 23 23 20
命令：D 20
删除后：20 20 20 23 23 23 20 20 20 23
命令：D 23
删除后：20 20 20 23 23 23 20 20 20 23
命令：E