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 package org.apache.xbean.naming.reference; 018 019 import java.util.LinkedHashMap; 020 import java.util.Map; 021 022 import javax.naming.NamingException; 023 import javax.naming.Reference; 024 import javax.naming.Context; 025 026 import org.apache.xbean.naming.context.ContextUtil; 027 028 /** 029 * @version $Rev: 355877 $ $Date: 2005-12-10 18:48:27 -0800 (Sat, 10 Dec 2005) $ 030 */ 031 public class CachingReference extends SimpleReference { 032 033 public static Object wrapReference(String fullName, Object value, Context context) { 034 if (value instanceof Reference && !(value instanceof CachingReference)) { 035 return new CachingReference(fullName, (Reference)value, context); 036 } 037 return value; 038 } 039 040 public static Map<String, Object> wrapReferences(Map<String, Object> bindings, Context context) { 041 LinkedHashMap<String, Object> newBindings = new LinkedHashMap<String, Object>(bindings); 042 for (Map.Entry<String, Object> entry : bindings.entrySet()) { 043 String name = entry.getKey(); 044 Object value = entry.getValue(); 045 if (value instanceof Reference && !(value instanceof CachingReference)) { 046 newBindings.put(name, new CachingReference(name, (Reference) value, context)); 047 } 048 } 049 return newBindings; 050 } 051 052 private final Object lock = new Object(); 053 private final String stringName; 054 private final Context context; 055 private final Reference reference; 056 private final String className; 057 private Object value; 058 059 public CachingReference(String fullName, Reference reference, Context context) { 060 this.stringName = fullName; 061 this.reference = reference; 062 className = reference.getClassName(); 063 this.context = context; 064 } 065 066 public Object getContent() throws NamingException { 067 synchronized(lock) { 068 if (value == null) { 069 value = ContextUtil.resolve(reference, stringName, null, context); 070 } 071 return value; 072 } 073 } 074 075 public String getClassName() { 076 return className; 077 } 078 }