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1   /*
2    *  Licensed to the Apache Software Foundation (ASF) under one
3    *  or more contributor license agreements.  See the NOTICE file
4    *  distributed with this work for additional information
5    *  regarding copyright ownership.  The ASF licenses this file
6    *  to you under the Apache License, Version 2.0 (the
7    *  "License"); you may not use this file except in compliance
8    *  with the License.  You may obtain a copy of the License at
9    *
10   *    http://www.apache.org/licenses/LICENSE-2.0
11   *
12   *  Unless required by applicable law or agreed to in writing,
13   *  software distributed under the License is distributed on an
14   *  "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
15   *  KIND, either express or implied.  See the License for the
16   *  specific language governing permissions and limitations
17   *  under the License.
18   *
19   */
20  package org.apache.directory.mavibot.btree;
21  
22  
23  import java.util.List;
24  
25  
26  /**
27   * The result of an insert operation, when the page has been split. It contains
28   * the new pivotal value, plus the reference on the two new pages.
29   * 
30   * @param <K> The type for the Key
31   * @param <V> The type for the stored value
32   * @author <a href="mailto:labs@labs.apache.org">Mavibot labs Project</a>
33   */
34  /* No qualifier */class SplitResult<K, V> extends AbstractResult<K, V> implements InsertResult<K, V>
35  {
36      /** The left child */
37      protected Page<K, V> leftPage;
38  
39      /** The right child */
40      protected Page<K, V> rightPage;
41  
42      /** The key pivot */
43      protected K pivot;
44  
45  
46      /**
47       * The default constructor for SplitResult.
48       * @param pivot The new key to insert into the parent
49       * @param leftPage The new left page
50       * @param rightPage The new right page
51       */
52      /* No qualifier */SplitResult( K pivot, Page<K, V> leftPage, Page<K, V> rightPage )
53      {
54          super();
55          this.pivot = pivot;
56          this.leftPage = leftPage;
57          this.rightPage = rightPage;
58      }
59  
60  
61      /**
62       * A constructor for SplitResult with copied pages.
63       * 
64       * @param copiedPages the list of copied pages
65       * @param pivot The new key to insert into the parent
66       * @param leftPage The new left page
67       * @param rightPage The new right page
68       */
69      /* No qualifier */SplitResult( List<Page<K, V>> copiedPages, K pivot, Page<K, V> leftPage, Page<K, V> rightPage )
70      {
71          super( copiedPages );
72          this.pivot = pivot;
73          this.leftPage = leftPage;
74          this.rightPage = rightPage;
75      }
76  
77  
78      /**
79       * @return the leftPage
80       */
81      /* No qualifier */Page<K, V> getLeftPage()
82      {
83          return leftPage;
84      }
85  
86  
87      /**
88       * @return the rightPage
89       */
90      /* No qualifier */Page<K, V> getRightPage()
91      {
92          return rightPage;
93      }
94  
95  
96      /**
97       * @return the pivot
98       */
99      /* No qualifier */K getPivot()
100     {
101         return pivot;
102     }
103 
104 
105     /**
106      * @see Object#toString()
107      */
108     public String toString()
109     {
110         StringBuilder sb = new StringBuilder();
111 
112         sb.append( "SplitResult, new pivot = " ).append( pivot );
113         sb.append( "\n    leftPage = " ).append( leftPage );
114         sb.append( "\n    rightPage = " ).append( rightPage );
115         sb.append( super.toString() );
116 
117         return sb.toString();
118     }
119 }