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.camel.impl.converter;
018    
019    import org.apache.camel.spi.TypeConverterRegistry;
020    
021    /**
022     * A caching proxy
023     *
024     * @version 
025     */
026    public class CachingInjector<T> {
027        private final TypeConverterRegistry repository;
028        private final Class<T> type;
029        private T instance;
030    
031        public CachingInjector(TypeConverterRegistry repository, Class<T> type) {
032            this.repository = repository;
033            this.type = type;
034        }
035    
036        public synchronized T newInstance() {
037            if (instance == null) {
038                instance = createInstance(type);
039            }
040            return instance;
041        }
042    
043        protected T createInstance(Class<T> t) {
044            return repository.getInjector().newInstance(t);
045        }
046    }