| 1 | /* |
| 2 | |
| 3 | Derby - Class org.apache.derby.impl.store.access.sort.Node |
| 4 | |
| 5 | Copyright 1997, 2004 The Apache Software Foundation or its licensors, as applicable. |
| 6 | |
| 7 | Licensed under the Apache License, Version 2.0 (the "License"); |
| 8 | you may not use this file except in compliance with the License. |
| 9 | You may obtain a copy of the License at |
| 10 | |
| 11 | http://www.apache.org/licenses/LICENSE-2.0 |
| 12 | |
| 13 | Unless required by applicable law or agreed to in writing, software |
| 14 | distributed under the License is distributed on an "AS IS" BASIS, |
| 15 | WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| 16 | See the License for the specific language governing permissions and |
| 17 | limitations under the License. |
| 18 | |
| 19 | */ |
| 20 | |
| 21 | package org.apache.derby.impl.store.access.sort; |
| 22 | |
| 23 | import org.apache.derby.iapi.services.sanity.SanityManager; |
| 24 | import org.apache.derby.iapi.types.DataValueDescriptor; |
| 25 | import org.apache.derby.impl.sql.execute.RowUtil; |
| 26 | |
| 27 | /** |
| 28 | A node in a balanced binary tree. This class is effectively a |
| 29 | struct to the balanced tree class. |
| 30 | |
| 31 | **/ |
| 32 | |
| 33 | final class Node |
| 34 | { |
| 35 | public int balance; |
| 36 | public Node leftLink; |
| 37 | public Node rightLink; |
| 38 | public DataValueDescriptor[] key; |
| 39 | public int id; |
| 40 | public Node dupChain; |
| 41 | public int aux; |
| 42 | |
| 43 | public Node(int id) |
| 44 | { |
| 45 | this.id = id; |
| 46 | reset(); |
| 47 | } |
| 48 | |
| 49 | public void reset() |
| 50 | { |
| 51 | balance = 0; |
| 52 | leftLink = null; |
| 53 | rightLink = null; |
| 54 | key = null; |
| 55 | dupChain = null; |
| 56 | aux = 0; |
| 57 | // Leave id alone |
| 58 | } |
| 59 | |
| 60 | public Node link(int which) |
| 61 | { |
| 62 | if (which < 0) |
| 63 | return leftLink; |
| 64 | else |
| 65 | return rightLink; |
| 66 | } |
| 67 | |
| 68 | public void setLink(int which, Node l) |
| 69 | { |
| 70 | if (which < 0) |
| 71 | leftLink = l; |
| 72 | else |
| 73 | rightLink = l; |
| 74 | } |
| 75 | |
| 76 | DataValueDescriptor[] getKey() |
| 77 | { |
| 78 | return key; |
| 79 | } |
| 80 | |
| 81 | public String toString() |
| 82 | { |
| 83 | if (SanityManager.DEBUG) |
| 84 | { |
| 85 | int lid = (leftLink == null) ? -1 : leftLink.id; |
| 86 | int rid = (rightLink == null) ? -1 : rightLink.id; |
| 87 | int did = (dupChain == null) ? -1 : dupChain.id; |
| 88 | return "{" |
| 89 | + " id=" + id |
| 90 | + " key=" + RowUtil.toString(key) |
| 91 | + " left=" + lid |
| 92 | + " right=" + rid |
| 93 | + " balance=" + balance |
| 94 | + " dupChain=" + did |
| 95 | + " aux= " + aux |
| 96 | + " }"; |
| 97 | } |
| 98 | else |
| 99 | { |
| 100 | return(null); |
| 101 | } |
| 102 | } |
| 103 | } |