View Javadoc

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;
21  
22  
23  import org.apache.directory.shared.ldap.constants.JndiPropertyConstants;
24  import org.apache.directory.shared.ldap.filter.ExprNode;
25  import org.apache.directory.shared.ldap.message.AliasDerefMode;
26  import org.apache.directory.shared.ldap.name.LdapDN;
27  import org.apache.directory.server.xdbm.IndexCursor;
28  import org.apache.directory.server.core.entry.ServerEntry;
29  
30  import javax.naming.directory.SearchControls;
31  
32  
33  /**
34   * Given a search filter and a scope the search engine identifies valid
35   * candidate entries returning their ids.
36   * 
37   * @author <a href="mailto:dev@directory.apache.org">Apache Directory Project</a>
38   * @version $Rev: 658798 $
39   */
40  public interface SearchEngine<E>
41  {
42      /**
43       * @todo put this in the right place
44       * The alias dereferencing mode key for JNDI providers 
45       */
46      String ALIASMODE_KEY = JndiPropertyConstants.JNDI_LDAP_DAP_DEREF_ALIASES;
47      /** 
48       * @todo put this in the right place
49       * The alias dereferencing mode value for JNDI providers 
50       */
51      String ALWAYS = "always";
52      /** 
53       * @todo put this in the right place
54       * The alias dereferencing mode value for JNDI providers 
55       */
56      String NEVER = "never";
57      /** 
58       * @todo put this in the right place
59       * The alias dereferencing mode value for JNDI providers 
60       */
61      String FINDING = "finding";
62      /** 
63       * @todo put this in the right place
64       * The alias dereferencing mode value for JNDI providers 
65       */
66      String SEARCHING = "searching";
67  
68  
69      /**
70       * Gets the optimizer for this DefaultSearchEngine.
71       *
72       * @return the optimizer
73       */
74      Optimizer getOptimizer();
75  
76  
77      /**
78       * Conducts a search on a database.
79       * 
80       * @param base the search base
81       * @param aliasDerefMode the alias dereferencing mode to use
82       * @param filter the search filter AST root
83       * @param searchCtls the JNDI search controls
84       * @return enumeration over SearchResults
85       * @throws Exception if the search fails
86       */
87      IndexCursor<Long,E> cursor( LdapDN base,
88                               AliasDerefMode aliasDerefMode,
89                               ExprNode filter,
90                               SearchControls searchCtls ) throws Exception;
91  
92  
93      /**
94       * Builds an Evaluator for a filter expression.
95       * 
96       * @param filter the filter root AST node
97       * @return true if the filter passes the entry, false otherwise
98       * @throws Exception if something goes wrong while accessing the db
99       */
100     Evaluator<? extends ExprNode, ServerEntry> evaluator( ExprNode filter ) throws Exception;
101 }