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            if (isGzip(contentEncoding)) {
048                ByteArrayOutputStream os = new ByteArrayOutputStream();
049                GZIPOutputStream gzip = new GZIPOutputStream(os);
050                try {
051                    IOHelper.copy(in, gzip);
052                    gzip.finish();
053                    return new ByteArrayInputStream(os.toByteArray());
054                } finally {
055                    IOHelper.close(gzip, "gzip");
056                    IOHelper.close(os, "byte array output stream");
057                }
058            } else {
059                return in;
060            }
061        }
062    
063        public static InputStream compressGzip(String contentEncoding, byte[] data) throws IOException {
064            if (isGzip(contentEncoding)) {
065                ByteArrayOutputStream os = null;
066                GZIPOutputStream gzip = null;
067                try {
068                    os = new ByteArrayOutputStream();
069                    gzip = new GZIPOutputStream(os);
070                    gzip.write(data);
071                    gzip.finish();
072                    return new ByteArrayInputStream(os.toByteArray());
073                } finally {
074                    IOHelper.close(gzip, "gzip");
075                    IOHelper.close(os, "byte array output stream");
076                }
077            } else {
078                return new ByteArrayInputStream(data);
079            }
080        }
081    
082        public static byte[] compressGZIP(byte[] data) throws IOException {
083            ByteArrayOutputStream os = new ByteArrayOutputStream();
084            GZIPOutputStream gzip = new GZIPOutputStream(os);
085            try {
086                gzip.write(data);
087                gzip.finish();
088                return os.toByteArray();
089            } finally {
090                IOHelper.close(gzip, "gzip");
091                IOHelper.close(os, "byte array output stream");
092            }
093        }
094    
095        public static boolean isGzip(Message message) {        
096            return isGzip(message.getHeader(Exchange.CONTENT_ENCODING, String.class), message.getExchange());
097        }
098        
099        public static boolean isGzip(String header , Exchange exchange) {
100            if (exchange == null || !exchange.getProperty(Exchange.SKIP_GZIP_ENCODING, Boolean.FALSE, Boolean.class)) {
101                return isGzip(header);
102            } else {
103                return false;
104            }
105        }
106    
107        public static boolean isGzip(String header) {
108            return header != null && header.toLowerCase(Locale.ENGLISH).contains("gzip");
109        }
110    }