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 */ 017package org.apache.activemq.jndi; 018 019import javax.naming.NameNotFoundException; 020import javax.naming.NamingException; 021 022/** 023 * Allows users to dynamically create items 024 * 025 * 026 */ 027public abstract class LazyCreateContext extends ReadOnlyContext { 028 public Object lookup(String name) throws NamingException { 029 try { 030 return super.lookup(name); 031 } catch (NameNotFoundException e) { 032 Object answer = createEntry(name); 033 if (answer == null) { 034 throw e; 035 } 036 internalBind(name, answer); 037 return answer; 038 } 039 } 040 041 protected abstract Object createEntry(String name); 042}