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     *      http://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     */
017    package org.apache.camel.util;
018    
019    import java.io.ByteArrayInputStream;
020    import java.io.ByteArrayOutputStream;
021    import java.io.IOException;
022    import java.io.InputStream;
023    import java.util.Locale;
024    import java.util.zip.GZIPInputStream;
025    import java.util.zip.GZIPOutputStream;
026    
027    import org.apache.camel.Exchange;
028    import org.apache.camel.Message;
029    
030    /**
031     * Helper class to help wrapping content into GZIP input and output streams.
032     */
033    public final class GZIPHelper {
034    
035        private GZIPHelper() {
036        }
037    
038        public static InputStream uncompressGzip(String contentEncoding, InputStream in) throws IOException {
039            if (isGzip(contentEncoding)) {
040                return new GZIPInputStream(in);
041            } else {
042                return in;
043            }
044        }
045        
046        public static InputStream compressGzip(String contentEncoding, InputStream in) throws IOException {
047    
048            if (isGzip(contentEncoding)) {
049                ByteArrayOutputStream os = new ByteArrayOutputStream();
050                GZIPOutputStream gzip = new GZIPOutputStream(os);
051                try {
052                    IOHelper.copy(in, gzip);
053                    gzip.finish();
054                    return new ByteArrayInputStream(os.toByteArray());
055                } finally {
056                    IOHelper.close(gzip, "gzip");
057                    IOHelper.close(os, "byte array output stream");
058                }
059            } else {
060                return in;
061            }
062    
063        }
064    
065        public static InputStream compressGzip(String contentEncoding, byte[] data) throws IOException {
066            if (isGzip(contentEncoding)) {
067                ByteArrayOutputStream os = null;
068                GZIPOutputStream gzip = null;
069                try {
070                    os = new ByteArrayOutputStream();
071                    gzip = new GZIPOutputStream(os);
072                    gzip.write(data);
073                    gzip.finish();
074                    return new ByteArrayInputStream(os.toByteArray());
075                } finally {
076                    IOHelper.close(gzip, "gzip");
077                    IOHelper.close(os, "byte array output stream");
078                }
079            } else {
080                return new ByteArrayInputStream(data);
081            }
082        }
083    
084        public static byte[] compressGZIP(byte[] data) throws IOException {
085            ByteArrayOutputStream os = new ByteArrayOutputStream();
086            GZIPOutputStream gzip = new GZIPOutputStream(os);
087            try {
088                gzip.write(data);
089                gzip.finish();
090                return os.toByteArray();
091            } finally {
092                IOHelper.close(gzip, "gzip");
093                IOHelper.close(os, "byte array output stream");
094            }
095        }
096    
097        public static boolean isGzip(Message message) {        
098            return isGzip(message.getHeader(Exchange.CONTENT_ENCODING, String.class), message.getExchange());
099        }
100        
101        public static boolean isGzip(String header , Exchange exchange) {
102            if (exchange == null || !exchange.getProperty(Exchange.SKIP_GZIP_ENCODING, Boolean.FALSE, Boolean.class)) {
103                return isGzip(header);
104            } else {
105                return false;
106            }
107        }
108    
109        public static boolean isGzip(String header) {
110            return header != null && header.toLowerCase(Locale.ENGLISH).contains("gzip");
111        }
112    }