1 /*
2 * Licensed to the Apache Software Foundation (ASF) under one or more
3 * contributor license agreements. See the NOTICE file distributed with
4 * this work for additional information regarding copyright ownership.
5 * The ASF licenses this file to You under the Apache License, Version 2.0
6 * (the "License"); you may not use this file except in compliance with
7 * the License. You may obtain a copy of the License at
8 *
9 * https://www.apache.org/licenses/LICENSE-2.0
10 *
11 * Unless required by applicable law or agreed to in writing, software
12 * distributed under the License is distributed on an "AS IS" BASIS,
13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14 * See the License for the specific language governing permissions and
15 * limitations under the License.
16 */
17 package org.apache.commons.configuration2.io;
18
19 import java.net.URL;
20
21 import org.apache.commons.lang3.StringUtils;
22
23 /**
24 * A specialized {@code FileLocationStrategy} implementation which searches for files on the class path.
25 * <p>
26 * This strategy implementation ignores the URL and the base path components of the passed in {@link FileLocator}. It
27 * tries to look up the file name on both the class path and the system class path.
28 * </p>
29 * <p>
30 * See {@link AbstractFileLocationStrategy} learn how to grant an deny URL schemes and hosts.
31 * </p>
32 *
33 * @see AbstractFileLocationStrategy
34 * @since 2.0
35 */
36 public class ClasspathLocationStrategy extends AbstractFileLocationStrategy {
37
38 /**
39 * Builds new instances of {@link ProvidedURLLocationStrategy}.
40 *
41 * @return a new builder.
42 * @since 2.15.0
43 */
44 public static StrategyBuilder<ClasspathLocationStrategy> builder() {
45 return new StrategyBuilder<>(ClasspathLocationStrategy::new);
46 }
47
48 /**
49 * Constructs a new instance.
50 */
51 public ClasspathLocationStrategy() {
52 // empty
53 }
54
55 /**
56 * Constructs a new instance.
57 *
58 * @param builder How to build the instance.
59 * @since 2.15.0
60 */
61 public ClasspathLocationStrategy(final AbstractBuilder<?, ?> builder) {
62 super(builder);
63 }
64
65 /**
66 * {@inheritDoc} This implementation looks up the locator's file name as a resource on the class path.
67 */
68 @Override
69 public URL locate(final FileSystem fileSystem, final FileLocator locator) {
70 return check(StringUtils.isEmpty(locator.getFileName()) ? null : FileLocatorUtils.getClasspathResource(locator.getFileName()));
71 }
72 }