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 * http://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
18 package org.apache.logging.log4j.core.config;
19
20 import java.io.ByteArrayInputStream;
21 import java.io.ByteArrayOutputStream;
22 import java.io.File;
23 import java.io.FileInputStream;
24 import java.io.IOException;
25 import java.io.InputStream;
26 import java.net.URL;
27
28 import org.apache.logging.log4j.core.util.Assert;
29
30 /**
31 * Represents the source for the logging configuration.
32 */
33 public class ConfigurationSource {
34 public static final ConfigurationSource NULL_SOURCE = new ConfigurationSource(new byte[0]);
35
36 private final File file;
37 private final URL url;
38 private final String location;
39 private final InputStream stream;
40 private final byte[] data;
41
42 /**
43 * Returns the contents of the specified {@code InputStream} as a byte array.
44 *
45 * @param inputStream the stream to read
46 * @return the contents of the specified stream
47 * @throws IOException if a problem occurred reading from the stream
48 */
49 private static byte[] toByteArray(final InputStream inputStream) throws IOException {
50 final int buffSize = Math.max(4096, inputStream.available());
51 final ByteArrayOutputStream contents = new ByteArrayOutputStream(buffSize);
52 final byte[] buff = new byte[buffSize];
53
54 int length = inputStream.read(buff);
55 while (length > 0) {
56 contents.write(buff, 0, length);
57 length = inputStream.read(buff);
58 }
59 return contents.toByteArray();
60 }
61
62 /**
63 * Constructs a new {@code ConfigurationSource} with the specified input stream. Since the stream is the only source
64 * of data, this constructor makes a copy of the stream contents.
65 *
66 * @param stream the input stream
67 * @throws IOException if an exception occurred reading from the specified stream
68 */
69 public ConfigurationSource(final InputStream stream) throws IOException {
70 this(toByteArray(stream));
71 }
72
73 private ConfigurationSource(final byte[] data) {
74 this.data = Assert.requireNonNull(data, "data is null");
75 this.stream = new ByteArrayInputStream(data);
76 this.file = null;
77 this.url = null;
78 this.location = null;
79 }
80
81 /**
82 * Constructs a new {@code ConfigurationSource} with the specified input stream that originated from the specified
83 * file.
84 *
85 * @param stream the input stream
86 * @param file the file where the input stream originated
87 */
88 public ConfigurationSource(final InputStream stream, final File file) {
89 this.stream = Assert.requireNonNull(stream, "stream is null");
90 this.file = Assert.requireNonNull(file, "file is null");
91 this.location = file.getAbsolutePath();
92 this.url = null;
93 this.data = null;
94 }
95
96 /**
97 * Constructs a new {@code ConfigurationSource} with the specified input stream that originated from the specified
98 * url.
99 *
100 * @param stream the input stream
101 * @param url the URL where the input stream originated
102 */
103 public ConfigurationSource(final InputStream stream, final URL url) {
104 this.stream = Assert.requireNonNull(stream, "stream is null");
105 this.url = Assert.requireNonNull(url, "URL is null");
106 this.location = url.toString();
107 this.file = null;
108 this.data = null;
109 }
110
111 /**
112 * Returns the file configuration source, or {@code null} if this configuration source is based on an URL or has
113 * neither a file nor an URL.
114 *
115 * @return the configuration source file, or {@code null}
116 */
117 public File getFile() {
118 return file;
119 }
120
121 /**
122 * Returns the configuration source URL, or {@code null} if this configuration source is based on a file or has
123 * neither a file nor an URL.
124 *
125 * @return the configuration source URL, or {@code null}
126 */
127 public URL getURL() {
128 return url;
129 }
130
131 /**
132 * Returns a string describing the configuration source file or URL, or {@code null} if this configuration source
133 * has neither a file nor an URL.
134 *
135 * @return a string describing the configuration source file or URL, or {@code null}
136 */
137 public String getLocation() {
138 return location;
139 }
140
141 /**
142 * Returns the input stream that this configuration source was constructed with.
143 *
144 * @return the input stream that this configuration source was constructed with.
145 */
146 public InputStream getInputStream() {
147 return stream;
148 }
149
150 /**
151 * Returns a new {@code ConfigurationSource} whose input stream is reset to the beginning.
152 *
153 * @return a new {@code ConfigurationSource}
154 * @throws IOException if a problem occurred while opening the new input stream
155 */
156 public ConfigurationSource resetInputStream() throws IOException {
157 if (file != null) {
158 return new ConfigurationSource(new FileInputStream(file), file);
159 } else if (url != null) {
160 return new ConfigurationSource(url.openStream(), url);
161 } else {
162 return new ConfigurationSource(data);
163 }
164 }
165
166 @Override
167 public String toString() {
168 if (location != null) {
169 return location;
170 }
171 if (this == NULL_SOURCE) {
172 return "NULL_SOURCE";
173 }
174 final int length = data == null ? -1 : data.length;
175 return "stream (" + length + " bytes, unknown location)";
176 }
177 }