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.api.ldap.model.schema.comparators;
21
22
23 import java.io.Serializable;
24 import java.util.Comparator;
25
26 import org.apache.directory.api.i18n.I18n;
27 import org.apache.directory.api.ldap.model.exception.LdapException;
28 import org.apache.directory.api.ldap.model.schema.LdapComparator;
29 import org.apache.directory.api.ldap.model.schema.SchemaManager;
30
31
32 /**
33 * A serializable wrapper around a Comparator which uses delayed initialization
34 * of the underlying wrapped comparator which is JIT resolved from a static
35 * global registry.
36 *
37 * @param <E> The type of object to compare
38 *
39 * @author <a href="mailto:dev@directory.apache.org">Apache Directory Project</a>
40 */
41 public class SerializableComparator<E> extends LdapComparator<E> implements Serializable
42 {
43 /** The serial version UID */
44 private static final long serialVersionUID = 2L;
45
46 /** the OID of the matchingRule for this comparator */
47 private String matchingRuleOid;
48
49 /** the transient wrapped comparator */
50 private transient Comparator<E> wrapped;
51
52 /** A reference to the schema manager */
53 private transient SchemaManager schemaManager;
54
55
56 /**
57 * Creates a new instance of SerializableComparator.
58 *
59 * @param matchingRuleOid The MatchingRule OID
60 */
61 public SerializableComparator( String matchingRuleOid )
62 {
63 super( matchingRuleOid );
64 this.matchingRuleOid = matchingRuleOid;
65 }
66
67
68 // ------------------------------------------------------------------------
69 // C O M P A R A T O R I M P L E M E N T A T I O N S
70 // ------------------------------------------------------------------------
71
72 /**
73 * {@inheritDoc}
74 */
75 @SuppressWarnings("unchecked")
76 @Override
77 public int compare( E o1, E o2 )
78 {
79 if ( wrapped == null )
80 {
81 try
82 {
83 wrapped = ( Comparator<E> ) schemaManager.lookupComparatorRegistry( matchingRuleOid );
84 }
85 catch ( LdapException le )
86 {
87 throw new RuntimeException( I18n.err( I18n.ERR_04221, matchingRuleOid ), le );
88 }
89 }
90
91 return wrapped.compare( o1, o2 );
92 }
93
94
95 /**
96 * @param schemaManager the schemaManager to set
97 */
98 @SuppressWarnings("unchecked")
99 @Override
100 public void setSchemaManager( SchemaManager schemaManager )
101 {
102 if ( wrapped == null )
103 {
104 try
105 {
106 wrapped = ( Comparator<E> )
107 schemaManager.lookupComparatorRegistry( matchingRuleOid );
108 }
109 catch ( LdapException ne )
110 {
111 // Not found : get the default comparator
112 wrapped = ( Comparator<E> )
113 new ComparableComparator<>( matchingRuleOid );
114 }
115 }
116
117 ( ( LdapComparator<E> ) wrapped ).setSchemaManager( schemaManager );
118 this.schemaManager = schemaManager;
119 }
120 }