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.commons.configuration2.resolver;
018
019import java.net.URL;
020import java.util.Map;
021
022/**
023 * Interface used for registering and retrieving PUBLICID to URL mappings.
024 *
025 * @since 1.7
026 */
027public interface EntityRegistry {
028    /**
029     * Gets a map with the entity IDs that have been registered using the {@code registerEntityId()} method.
030     *
031     * @return a map with the registered entity IDs
032     */
033    Map<String, URL> getRegisteredEntities();
034
035    /**
036     * <p>
037     * Registers the specified URL for the specified public identifier.
038     * </p>
039     * <p>
040     * This implementation maps {@code PUBLICID}'s to URLs (from which the resource will be loaded). A common use case for
041     * this method is to register local URLs (possibly computed at runtime by a class loader) for DTDs and Schemas. This
042     * allows the performance advantage of using a local version without having to ensure every {@code SYSTEM} URI on every
043     * processed XML document is local. This implementation provides only basic functionality. If more sophisticated
044     * features are required, either calling {@code XMLConfiguration.setDocumentBuilder(DocumentBuilder)} to set a custom
045     * {@code DocumentBuilder} (which also can be initialized with a custom {@code EntityResolver}) or creating a custom
046     * entity resolver and registering it with the XMLConfiguration is recommended.
047     * </p>
048     *
049     * @param publicId Public identifier of the Entity to be resolved
050     * @param entityURL The URL to use for reading this Entity
051     * @throws IllegalArgumentException if the public ID is undefined
052     */
053    void registerEntityId(String publicId, URL entityURL);
054}