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.spi;
018    
019    import java.util.Map;
020    
021    /**
022     * Represents a service registry which may be implemented via a Spring ApplicationContext,
023     * via JNDI, a simple Map or the OSGi Service Registry
024     *
025     * @version 
026     */
027    public interface Registry {
028    
029        /**
030         * Looks up a service in the registry based purely on name,
031         * returning the service or <tt>null</tt> if it could not be found.
032         *
033         * @param name the name of the service
034         * @return the service from the registry or <tt>null</tt> if it could not be found
035         */
036        Object lookup(String name);
037    
038        /**
039         * Looks up a service in the registry, returning the service or <tt>null</tt> if it could not be found.
040         *
041         * @param name the name of the service
042         * @param type the type of the required service
043         * @return the service from the registry or <tt>null</tt> if it could not be found
044         */
045        <T> T lookup(String name, Class<T> type);
046    
047        /**
048         * Looks up services in the registry by their type.
049         * <p/>
050         * <b>Note:</b> Not all registry implementations support this feature,
051         * such as the {@link org.apache.camel.impl.JndiRegistry}.
052         *
053         * @param type  the type of the registered services
054         * @return the types found, with their id as the key. Returns an empty Map if none found.
055         */
056        <T> Map<String, T> lookupByType(Class<T> type);
057    
058    }