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.camel.component.extension;
018
019/**
020 * Marker interface for component extensions.
021 * <p/>
022 * An extension is a feature provided by the component such as ComponentVerifier,
023 * ServiceMetaData.
024 */
025public interface ComponentExtension {
026    /**
027     * Access the underlying concrete ComponentExtension implementation to
028     * provide access to further features.
029     *
030     * @param clazz the proprietary class or interface of the underlying concrete ComponentExtension.
031     * @return an instance of the underlying concrete ComponentExtension as the required type.
032     */
033    default <T extends ComponentExtension> T unwrap(Class<T> clazz) {
034        if (ComponentExtension.class.isAssignableFrom(clazz)) {
035            return clazz.cast(this);
036        }
037
038        throw new IllegalArgumentException(
039            "Unable to unwrap this ComponentExtension type (" + getClass() + ") to the required type (" + clazz + ")"
040        );
041    }
042}