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.server.core.partition.impl.btree.jdbm; 21 22 23 import org.apache.directory.server.core.avltree.AvlTree; 24 25 26 /** 27 * A wrapper around duplicate key values. This class wraps either an AvlTree 28 * or a BTreeRedirect. The AvlTree and BTreeRedirect forms are used for the 29 * two value persistence mechanisms used to implement duplicate keys over JDBM 30 * btrees. 31 * 32 * @author <a href="mailto:dev@directory.apache.org">Apache Directory Project</a> 33 * @version $Rev$ 34 */ 35 public class DupsContainer<V> 36 { 37 private final AvlTree<V> avlTree; 38 private final BTreeRedirect btreeRedirect; 39 40 41 DupsContainer( AvlTree<V> avlTree ) 42 { 43 this.avlTree = avlTree; 44 btreeRedirect = null; 45 } 46 47 48 DupsContainer( BTreeRedirect btreeRedirect ) 49 { 50 avlTree = null; 51 this.btreeRedirect = btreeRedirect; 52 } 53 54 55 final boolean isBTreeRedirect() 56 { 57 return btreeRedirect != null; 58 } 59 60 61 final boolean isAvlTree() 62 { 63 return avlTree != null; 64 } 65 66 67 final AvlTree<V> getAvlTree() 68 { 69 if ( avlTree == null ) 70 { 71 throw new IllegalStateException( "this is not a avlTree container" ); 72 } 73 74 return avlTree; 75 } 76 77 78 final BTreeRedirect getBTreeRedirect() 79 { 80 if ( btreeRedirect == null ) 81 { 82 throw new IllegalStateException( "this is not a btreeRedirect container" ); 83 } 84 85 return btreeRedirect; 86 } 87 }