1 /*
2 * Licensed to the Apache Software Foundation (ASF) under one
3 * or more contributor license agreements. See the NOTICE file
4 * distributed with this work for additional information
5 * regarding copyright ownership. The ASF licenses this file
6 * to you under the Apache License, Version 2.0 (the
7 * "License"); you may not use this file except in compliance
8 * with the License. You may obtain a copy of the License at
9 *
10 * http://www.apache.org/licenses/LICENSE-2.0
11 *
12 * Unless required by applicable law or agreed to in writing,
13 * software distributed under the License is distributed on an
14 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
15 * KIND, either express or implied. See the License for the
16 * specific language governing permissions and limitations
17 * under the License.
18 */
19 package org.eclipse.aether.util;
20
21 import java.io.IOException;
22 import java.nio.file.Files;
23 import java.nio.file.Path;
24 import java.nio.file.Paths;
25
26 import org.eclipse.aether.RepositorySystemSession;
27
28 import static java.util.Objects.requireNonNull;
29
30 /**
31 * A utility class to calculate (and create if needed) paths backed by directories using configuration properties from
32 * repository system session and others.
33 *
34 * @see RepositorySystemSession#getConfigProperties()
35 * @see RepositorySystemSession#getLocalRepository()
36 * @since 1.9.0
37 */
38 public final class DirectoryUtils {
39 private DirectoryUtils() {
40 // hide constructor
41 }
42
43 /**
44 * Creates {@link Path} instance out of passed in {@code name} parameter. May create a directory on resulting path,
45 * if not exist, when invoked with {@code mayCreate} being {@code true}. Never returns {@code null}.
46 * <p>
47 * Following outcomes may happen:
48 * <ul>
49 * <li>{@code name} is absolute path - results in {@link Path} instance created directly from name.</li>
50 * <li>{@code name} is relative path - results in {@link Path} instance resolved against {@code base} parameter.
51 * </li>
52 * </ul>
53 * Resulting path is being checked is a directory, and if not, it will be created if {@code mayCreate} is
54 * {@code true}. If resulting path exist but is not a directory, this method will throw.
55 *
56 * @param name The name to create directory with, cannot be {@code null}.
57 * @param base The base {@link Path} to resolve name, if it is relative path, cannot be {@code null}.
58 * @param mayCreate If resulting path does not exist, should it create?
59 * @return The {@link Path} instance that is resolved and backed by existing directory.
60 * @throws IOException If some IO related errors happens.
61 */
62 public static Path resolveDirectory(String name, Path base, boolean mayCreate) throws IOException {
63 requireNonNull(name, "name is null");
64 requireNonNull(base, "base is null");
65 final Path namePath = Paths.get(name);
66 final Path result;
67 if (namePath.isAbsolute()) {
68 result = namePath.normalize();
69 } else {
70 result = base.resolve(namePath).normalize();
71 }
72
73 if (!Files.exists(result)) {
74 if (mayCreate) {
75 Files.createDirectories(result);
76 }
77 } else if (!Files.isDirectory(result)) {
78 throw new IOException("Path exists, but is not a directory: " + result);
79 }
80 return result;
81 }
82
83 /**
84 * Creates {@link Path} instance out of session configuration, and (if relative) resolve it against local
85 * repository basedir. Pre-populates values and invokes {@link #resolveDirectory(String, Path, boolean)}.
86 * <p>
87 * For this method to work, {@link org.eclipse.aether.repository.LocalRepository#getBasedir()} must return
88 * non-{@code null} value, otherwise {@link NullPointerException} is thrown.
89 *
90 * @param session The session, may not be {@code null}.
91 * @param defaultName The default value if not present in session configuration, may not be {@code null}.
92 * @param nameKey The key to look up for in session configuration to obtain user set value.
93 * @param mayCreate If resulting path does not exist, should it create?
94 * @return The {@link Path} instance that is resolved and backed by existing directory.
95 * @throws IOException If some IO related errors happens.
96 * @see #resolveDirectory(String, Path, boolean)
97 */
98 public static Path resolveDirectory(
99 RepositorySystemSession session, String defaultName, String nameKey, boolean mayCreate) throws IOException {
100 requireNonNull(session, "session is null");
101 requireNonNull(defaultName, "defaultName is null");
102 requireNonNull(nameKey, "nameKey is null");
103 requireNonNull(session.getLocalRepository().getBasedir(), "session.localRepository.basedir is null");
104 return resolveDirectory(
105 ConfigUtils.getString(session, defaultName, nameKey),
106 session.getLocalRepository().getBasedir().toPath(),
107 mayCreate);
108 }
109 }