mcs/class/System.Data/System.Data/Node.cs

   1 using System;
   2
   3 namespace System.Data
   4 {
   5         /// <summary>
   6         /// Summary description for Node.
   7         /// </summary>
   8         public class Node
   9         {
  10                 protected int _iBalance;    // currently, -2 means 'deleted'
  11                 internal Node _nNext;       // node of next index (nNext==null || nNext.iId=iId+1)
  12                 protected Node _nLeft;
  13                 protected Node _nRight;
  14                 protected Node _nParent;
  15
  16                 protected DataRow _row;
  17
  18                 public Node(DataRow row)
  19                 {
  20                         _row = row;
  21                 }
  22
  23                 internal int GetBalance()
  24                 {
  25                         if (_iBalance == -2)
  26                                 throw new Exception ("Node is deleted.");
  27
  28                         return _iBalance;
  29                 }
  30
  31                 internal void Delete()
  32                 {
  33                         _iBalance = -2;
  34                         _nLeft = null;
  35                         _nRight = null;
  36                         _nParent = null;
  37                 }
  38
  39
  40                 internal DataRow Row
  41                 {
  42                         get {
  43                                 return _row;
  44                         }
  45                 }
  46
  47                 internal Node Left
  48                 {
  49                         get {
  50                                 if (_iBalance == -2)
  51                                         throw new Exception ("Node is deleted.");
  52
  53                                 return _nLeft;
  54                         }
  55
  56                         set {
  57                                 if (_iBalance == -2)
  58                                         throw new Exception ("Node is deleted.");
  59
  60                                 _nLeft = value;
  61                         }
  62                 }
  63
  64                 internal Node Right
  65                 {
  66                         get {
  67                                 if (_iBalance == -2)
  68                                         throw new Exception ("Node is deleted.");
  69                                 return _nRight;
  70                         }
  71
  72                         set {
  73                                 if (_iBalance == -2)
  74                                         throw new Exception ("Node is deleted.");
  75
  76                                 _nRight = value;
  77                         }
  78                 }
  79
  80
  81                 internal Node Parent
  82                 {
  83                         get {
  84                                 if (_iBalance == -2)
  85                                         throw new Exception ("Node is deleted.");
  86
  87                                 return _nParent;
  88                         }
  89
  90                         set {
  91                                 if (_iBalance == -2)
  92                                         throw new Exception ("Node is deleted.");
  93                                 _nParent = value;
  94                         }
  95                 }
  96
  97                 internal bool IsRoot()
  98                 {
  99                         return _nParent == null;
 100                 }
 101
 102
 103                 internal void SetBalance(int b)
 104                 {
 105
 106                         if (_iBalance == -2)
 107                                 throw new Exception ("Node is deleted.");
 108
 109                         _iBalance = b;
 110                 }
 111
 112                 internal bool From()
 113                 {
 114
 115                         if (this.IsRoot()){
 116                                 return true;
 117                         }
 118
 119                         if (_iBalance == -2)
 120                                 throw new Exception ("Node is deleted.");
 121                         Node parent = Parent;
 122
 123                         return Equals(parent.Left);
 124                 }
 125
 126                 internal Object[] GetData()
 127                 {
 128
 129                         if (_iBalance == -2)
 130                                 throw new Exception ("Node is deleted.");
 131                         return _row.ItemArray;
 132                 }
 133
 134                 internal bool Equals(Node n)
 135                 {
 136
 137                         if (_iBalance == -2)
 138                                 throw new Exception ("Node is deleted.");
 139
 140                         return n == this;
 141                 }
 142         }
 143 }