001 /*
002 * Licensed to the Apache Software Foundation (ASF) under one or more
003 * contributor license agreements. See the NOTICE file distributed with
004 * this work for additional information regarding copyright ownership.
005 * The ASF licenses this file to You under the Apache License, Version 2.0
006 * (the "License"); you may not use this file except in compliance with
007 * the License. You may obtain a copy of the License at
008 *
009 * http://www.apache.org/licenses/LICENSE-2.0
010 *
011 * Unless required by applicable law or agreed to in writing, software
012 * distributed under the License is distributed on an "AS IS" BASIS,
013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014 * See the License for the specific language governing permissions and
015 * limitations under the License.
016 */
017
018 package org.apache.commons.chain.impl;
019
020 import java.util.HashMap;
021 import java.util.Iterator;
022 import java.util.Map;
023 import org.apache.commons.chain.Catalog;
024 import org.apache.commons.chain.CatalogFactory;
025
026 /**
027 * <p>A simple implementation of {@link CatalogFactory}.</p>
028 *
029 * @author Sean Schofield
030 * @version $Revision: 480477 $ $Date: 2006-11-29 08:34:52 +0000 (Wed, 29 Nov 2006) $
031 */
032
033 public class CatalogFactoryBase extends CatalogFactory {
034
035
036 // ----------------------------------------------------------- Constructors
037
038
039 /**
040 * <p>Construct an empty instance of {@link CatalogFactoryBase}. This
041 * constructor is intended solely for use by {@link CatalogFactory}.</p>
042 */
043 public CatalogFactoryBase() { }
044
045
046 // ----------------------------------------------------- Instance Variables
047
048
049 /**
050 * <p>The default {@link Catalog} for this {@link CatalogFactory}.</p>
051 */
052 private Catalog catalog = null;
053
054
055 /**
056 * <p>Map of named {@link Catalog}s, keyed by catalog name.</p>
057 */
058 private Map catalogs = new HashMap();
059
060
061 // --------------------------------------------------------- Public Methods
062
063
064 /**
065 * <p>Gets the default instance of Catalog associated with the factory
066 * (if any); otherwise, return <code>null</code>.</p>
067 *
068 * @return the default Catalog instance
069 */
070 public Catalog getCatalog() {
071
072 return catalog;
073
074 }
075
076
077 /**
078 * <p>Sets the default instance of Catalog associated with the factory.</p>
079 *
080 * @param catalog the default Catalog instance
081 */
082 public void setCatalog(Catalog catalog) {
083
084 this.catalog = catalog;
085
086 }
087
088
089 /**
090 * <p>Retrieves a Catalog instance by name (if any); otherwise
091 * return <code>null</code>.</p>
092 *
093 * @param name the name of the Catalog to retrieve
094 * @return the specified Catalog
095 */
096 public Catalog getCatalog(String name) {
097
098 synchronized (catalogs) {
099 return (Catalog) catalogs.get(name);
100 }
101
102 }
103
104
105 /**
106 * <p>Adds a named instance of Catalog to the factory (for subsequent
107 * retrieval later).</p>
108 *
109 * @param name the name of the Catalog to add
110 * @param catalog the Catalog to add
111 */
112 public void addCatalog(String name, Catalog catalog) {
113
114 synchronized (catalogs) {
115 catalogs.put(name, catalog);
116 }
117
118 }
119
120
121 /**
122 * <p>Return an <code>Iterator</code> over the set of named
123 * {@link Catalog}s known to this {@link CatalogFactory}.
124 * If there are no known catalogs, an empty Iterator is returned.</p>
125 * @return An Iterator of the names of the Catalogs known by this factory.
126 */
127 public Iterator getNames() {
128
129 synchronized (catalogs) {
130 return catalogs.keySet().iterator();
131 }
132
133 }
134
135
136 }