001 /*
002 * Licensed to the Apache Software Foundation (ASF) under one
003 * or more contributor license agreements. See the NOTICE file
004 * distributed with this work for additional information
005 * regarding copyright ownership. The ASF licenses this file
006 * to you under the Apache License, Version 2.0 (the
007 * "License"); you may not use this file except in compliance
008 * with the License. You may obtain a copy of the License at
009 *
010 * http://www.apache.org/licenses/LICENSE-2.0
011 *
012 * Unless required by applicable law or agreed to in writing,
013 * software distributed under the License is distributed on an
014 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
015 * KIND, either express or implied. See the License for the
016 * specific language governing permissions and limitations
017 * under the License.
018 */
019 package org.apache.commons.compress.compressors;
020
021 import java.io.IOException;
022 import java.io.InputStream;
023 import java.io.OutputStream;
024
025 import org.apache.commons.compress.compressors.bzip2.BZip2CompressorInputStream;
026 import org.apache.commons.compress.compressors.bzip2.BZip2CompressorOutputStream;
027 import org.apache.commons.compress.compressors.gzip.GzipCompressorInputStream;
028 import org.apache.commons.compress.compressors.gzip.GzipCompressorOutputStream;
029 import org.apache.commons.compress.compressors.xz.XZCompressorInputStream;
030 import org.apache.commons.compress.compressors.xz.XZCompressorOutputStream;
031 import org.apache.commons.compress.compressors.pack200.Pack200CompressorInputStream;
032 import org.apache.commons.compress.compressors.pack200.Pack200CompressorOutputStream;
033
034 /**
035 * <p>Factory to create Compressor[In|Out]putStreams from names. To add other
036 * implementations you should extend CompressorStreamFactory and override the
037 * appropriate methods (and call their implementation from super of course).</p>
038 *
039 * Example (Compressing a file):
040 *
041 * <pre>
042 * final OutputStream out = new FileOutputStream(output);
043 * CompressorOutputStream cos =
044 * new CompressorStreamFactory().createCompressorOutputStream(CompressorStreamFactory.BZIP2, out);
045 * IOUtils.copy(new FileInputStream(input), cos);
046 * cos.close();
047 * </pre>
048 *
049 * Example (Compressing a file):
050 * <pre>
051 * final InputStream is = new FileInputStream(input);
052 * CompressorInputStream in =
053 * new CompressorStreamFactory().createCompressorInputStream(CompressorStreamFactory.BZIP2, is);
054 * IOUtils.copy(in, new FileOutputStream(output));
055 * in.close();
056 * </pre>
057 *
058 * @Immutable
059 */
060 public class CompressorStreamFactory {
061
062 /**
063 * Constant used to identify the BZIP2 compression algorithm.
064 * @since Commons Compress 1.1
065 */
066 public static final String BZIP2 = "bzip2";
067
068 /**
069 * Constant used to identify the GZIP compression algorithm.
070 * @since Commons Compress 1.1
071 */
072 public static final String GZIP = "gz";
073 /**
074 * Constant used to identify the PACK200 compression algorithm.
075 * @since Commons Compress 1.3
076 */
077 public static final String PACK200 = "pack200";
078
079 /**
080 * Constant used to identify the XZ compression method.
081 * @since Commons Compress 1.4
082 */
083 public static final String XZ = "xz";
084
085 /**
086 * Create an compressor input stream from an input stream, autodetecting
087 * the compressor type from the first few bytes of the stream. The InputStream
088 * must support marks, like BufferedInputStream.
089 *
090 * @param in the input stream
091 * @return the compressor input stream
092 * @throws CompressorException if the compressor name is not known
093 * @throws IllegalArgumentException if the stream is null or does not support mark
094 * @since Commons Compress 1.1
095 */
096 public CompressorInputStream createCompressorInputStream(final InputStream in)
097 throws CompressorException {
098 if (in == null) {
099 throw new IllegalArgumentException("Stream must not be null.");
100 }
101
102 if (!in.markSupported()) {
103 throw new IllegalArgumentException("Mark is not supported.");
104 }
105
106 final byte[] signature = new byte[12];
107 in.mark(signature.length);
108 try {
109 int signatureLength = in.read(signature);
110 in.reset();
111
112 if (BZip2CompressorInputStream.matches(signature, signatureLength)) {
113 return new BZip2CompressorInputStream(in);
114 }
115
116 if (GzipCompressorInputStream.matches(signature, signatureLength)) {
117 return new GzipCompressorInputStream(in);
118 }
119
120 if (XZCompressorInputStream.matches(signature, signatureLength)) {
121 return new XZCompressorInputStream(in);
122 }
123
124 if (Pack200CompressorInputStream.matches(signature, signatureLength)) {
125 return new Pack200CompressorInputStream(in);
126 }
127
128 } catch (IOException e) {
129 throw new CompressorException("Failed to detect Compressor from InputStream.", e);
130 }
131
132 throw new CompressorException("No Compressor found for the stream signature.");
133 }
134
135 /**
136 * Create a compressor input stream from a compressor name and an input stream.
137 *
138 * @param name of the compressor, i.e. "gz", "bzip2", "xz", or "pack200"
139 * @param in the input stream
140 * @return compressor input stream
141 * @throws CompressorException if the compressor name is not known
142 * @throws IllegalArgumentException if the name or input stream is null
143 */
144 public CompressorInputStream createCompressorInputStream(final String name,
145 final InputStream in) throws CompressorException {
146 if (name == null || in == null) {
147 throw new IllegalArgumentException(
148 "Compressor name and stream must not be null.");
149 }
150
151 try {
152
153 if (GZIP.equalsIgnoreCase(name)) {
154 return new GzipCompressorInputStream(in);
155 }
156
157 if (BZIP2.equalsIgnoreCase(name)) {
158 return new BZip2CompressorInputStream(in);
159 }
160
161 if (XZ.equalsIgnoreCase(name)) {
162 return new XZCompressorInputStream(in);
163 }
164
165 if (PACK200.equalsIgnoreCase(name)) {
166 return new Pack200CompressorInputStream(in);
167 }
168
169 } catch (IOException e) {
170 throw new CompressorException(
171 "Could not create CompressorInputStream.", e);
172 }
173 throw new CompressorException("Compressor: " + name + " not found.");
174 }
175
176 /**
177 * Create an compressor output stream from an compressor name and an input stream.
178 *
179 * @param name the compressor name, i.e. "gz", "bzip2", "xz", or "pack200"
180 * @param out the output stream
181 * @return the compressor output stream
182 * @throws CompressorException if the archiver name is not known
183 * @throws IllegalArgumentException if the archiver name or stream is null
184 */
185 public CompressorOutputStream createCompressorOutputStream(
186 final String name, final OutputStream out)
187 throws CompressorException {
188 if (name == null || out == null) {
189 throw new IllegalArgumentException(
190 "Compressor name and stream must not be null.");
191 }
192
193 try {
194
195 if (GZIP.equalsIgnoreCase(name)) {
196 return new GzipCompressorOutputStream(out);
197 }
198
199 if (BZIP2.equalsIgnoreCase(name)) {
200 return new BZip2CompressorOutputStream(out);
201 }
202
203 if (XZ.equalsIgnoreCase(name)) {
204 return new XZCompressorOutputStream(out);
205 }
206
207 if (PACK200.equalsIgnoreCase(name)) {
208 return new Pack200CompressorOutputStream(out);
209 }
210
211 } catch (IOException e) {
212 throw new CompressorException(
213 "Could not create CompressorOutputStream", e);
214 }
215 throw new CompressorException("Compressor: " + name + " not found.");
216 }
217 }