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 *     https://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.io;
018
019import java.net.URL;
020
021/**
022 * A specialized implementation of {@code FileLocationStrategy} which checks whether a passed in {@link FileLocator}
023 * already has a defined URL.
024 * <p>
025 * {@link FileLocator} objects that have a URL already reference a file in an unambiguous way. Therefore, this strategy
026 * just returns the URL of the passed in {@code FileLocator}. It can be used as a first step of the file resolving
027 * process. If it fails, more sophisticated attempts for resolving the file can be made.
028 * </p>
029 * <p>
030 * See {@link AbstractFileLocationStrategy} learn how to grant an deny URL schemes and hosts.
031 * </p>
032 *
033 * @see AbstractFileLocationStrategy
034 * @since 2.0
035 */
036public class ProvidedURLLocationStrategy extends AbstractFileLocationStrategy {
037
038    /**
039     * Builds new instances of {@link ProvidedURLLocationStrategy}.
040     *
041     * @return a new builder.
042     * @since 2.15.0
043     */
044    public static StrategyBuilder<ProvidedURLLocationStrategy> builder() {
045        return new StrategyBuilder<>(ProvidedURLLocationStrategy::new);
046    }
047
048    /**
049     * Constructs a new instance where URL resources are bound by {@link AbstractFileLocationStrategy.AbstractBuilder}.
050     */
051    public ProvidedURLLocationStrategy() {
052    }
053
054    /**
055     * Constructs a new instance where URL resources are bound by {@link AbstractFileLocationStrategy.AbstractBuilder}.
056     *
057     * @param builder How to build the instance.
058     * @since 2.15.0
059     */
060    public ProvidedURLLocationStrategy(final AbstractBuilder<?, ?> builder) {
061        super(builder);
062    }
063
064    /**
065     * {@inheritDoc} This implementation just returns the URL stored in the given {@code FileLocator}.
066     */
067    @Override
068    public URL locate(final FileSystem fileSystem, final FileLocator locator) {
069        return check(locator.getSourceURL());
070    }
071
072}