001 /**
002 *
003 * Copyright 2004 Protique Ltd
004 *
005 * Licensed under the Apache License, Version 2.0 (the "License");
006 * you may not use this file except in compliance with the License.
007 * 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.activemq.jndi;
019
020 import javax.naming.NameNotFoundException;
021 import javax.naming.NamingException;
022
023 /**
024 * Allows users to dynamically create items
025 *
026 * @version $Revision: 1.1 $
027 */
028 public abstract class LazyCreateContext extends ReadOnlyContext {
029 public Object lookup(String name) throws NamingException {
030 try {
031 return super.lookup(name);
032 }
033 catch (NameNotFoundException e) {
034 Object answer = createEntry(name);
035 if (answer == null) {
036 throw e;
037 }
038 internalBind(name, answer);
039 return answer;
040 }
041 }
042
043 protected abstract Object createEntry(String name);
044 }