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.xdbm.search.evaluator; 21 22 23 import org.apache.directory.api.ldap.model.entry.Entry; 24 import org.apache.directory.api.ldap.model.exception.LdapException; 25 import org.apache.directory.api.ldap.model.filter.ScopeNode; 26 import org.apache.directory.server.i18n.I18n; 27 import org.apache.directory.server.xdbm.IndexEntry; 28 import org.apache.directory.server.xdbm.Store; 29 import org.apache.directory.server.xdbm.search.Evaluator; 30 31 32 /** 33 * Evaluates base level scope assertions on candidates using an entry database. 34 * 35 * @author <a href="mailto:dev@directory.apache.org">Apache Directory Project</a> 36 */ 37 public class BaseLevelScopeEvaluator<E> implements Evaluator<ScopeNode> 38 { 39 /** The ScopeNode containing initial search scope constraints */ 40 private final ScopeNode node; 41 42 /** The entry identifier of the scope base */ 43 private final String baseId; 44 45 /** True if the scope requires alias dereferencing while searching */ 46 private final boolean dereferencing; 47 48 /** the entry db storing entries */ 49 private final Store db; 50 51 52 /** 53 * Creates a one level scope node Evaluator for search expressions. 54 * 55 * @param node the scope node 56 * @param db the database used to evaluate scope node 57 * @throws Exception on db access failure 58 */ 59 public BaseLevelScopeEvaluator( Store db, ScopeNode node ) throws Exception 60 { 61 this.node = node; 62 63 this.db = db; 64 baseId = node.getBaseId(); 65 dereferencing = node.getDerefAliases().isDerefInSearching() || node.getDerefAliases().isDerefAlways(); 66 } 67 68 69 /** 70 * Asserts whether or not a candidate has one level scope while taking 71 * alias dereferencing into account. 72 * 73 * TODO - terribly inefficient - would benefit from exposing the id of an 74 * entry within the Entry 75 * 76 * {@inheritDoc} 77 */ 78 public boolean evaluate( Entry candidate ) throws Exception 79 { 80 throw new UnsupportedOperationException( I18n.err( I18n.ERR_721 ) ); 81 } 82 83 84 /** 85 * Asserts whether or not a candidate has one level scope while taking 86 * alias dereferencing into account. 87 * 88 * @param candidate the candidate to assert 89 * @return true if the candidate is within one level scope 90 * @throws Exception if db lookups fail 91 * @see org.apache.directory.server.xdbm.search.Evaluator#evaluate(IndexEntry) 92 */ 93 public boolean evaluate( IndexEntry<?, String> indexEntry ) throws LdapException 94 { 95 Entry entry = indexEntry.getEntry(); 96 97 // Fetch the entry 98 if ( null == entry ) 99 { 100 entry = db.fetch( indexEntry.getId() ); 101 102 if ( null == entry ) 103 { 104 // The entry is not anymore present : get out 105 return false; 106 } 107 108 indexEntry.setEntry( entry ); 109 } 110 111 return true; 112 } 113 114 115 public ScopeNode getExpression() 116 { 117 return node; 118 } 119 120 121 /** 122 * Gets the id of the search base associated with the ScopeNode expression. 123 * 124 * @return identifier of the search base 125 */ 126 public String getBaseId() 127 { 128 return baseId; 129 } 130 131 132 /** 133 * Gets whether or not dereferencing is enabled for this evaluator. 134 * 135 * @return true if dereferencing is enabled, false otherwise 136 */ 137 public boolean isDereferencing() 138 { 139 return dereferencing; 140 } 141 142 143 /** 144 * @see Object#toString() 145 */ 146 public String toString( String tabs ) 147 { 148 StringBuilder sb = new StringBuilder(); 149 150 sb.append( tabs ).append( "BaseLevelScopEvaluator : " ).append( node ).append( "\n" ); 151 152 return sb.toString(); 153 } 154 155 156 /** 157 * @see Object#toString() 158 */ 159 public String toString() 160 { 161 return toString( "" ); 162 } 163 }