Source code

001package org.apache.archiva.checksum;
002
003/*
004 * Licensed to the Apache Software Foundation (ASF) under one
005 * or more contributor license agreements.  See the NOTICE file
006 * distributed with this work for additional information
007 * regarding copyright ownership.  The ASF licenses this file
008 * to you under the Apache License, Version 2.0 (the
009 * "License"); you may not use this file except in compliance
010 * with the License.  You may obtain a copy of the License at
011 *
012 *  http://www.apache.org/licenses/LICENSE-2.0
013 *
014 * Unless required by applicable law or agreed to in writing,
015 * software distributed under the License is distributed on an
016 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
017 * KIND, either express or implied.  See the License for the
018 * specific language governing permissions and limitations
019 * under the License.
020 */
021
022import java.io.IOException;
023import java.io.InputStream;
024import java.io.OutputStream;
025import java.util.List;
026import java.util.stream.Collectors;
027
028/**
029 *
030 * Class that handles checksums with streams.
031 *
032 * @author Martin Stockhammer <martin_s@apache.org>
033 */
034public class StreamingChecksum
035{
036    static final int BUFFER_SIZE=4096;
037
038    public static void updateChecksums( InputStream input, List<ChecksumAlgorithm> algorithms, List<OutputStream> checksumOutput) {
039        List<Checksum> checksums = algorithms.stream().map(a -> new Checksum( a )).collect( Collectors.toList());
040        byte[] buffer = new byte[BUFFER_SIZE];
041        int read;
042        try
043        {
044            while ( ( read = input.read( buffer ) ) >= 0 )
045            {
046                for (Checksum cs : checksums ) {
047                    cs.update( buffer, 0, read );
048                }
049            }
050            int minIndex = Math.min(algorithms.size(), checksums.size());
051            for (int csIndex = 0; csIndex<minIndex; csIndex++) {
052                Checksum cs = checksums.get(csIndex);
053                cs.finish();
054                OutputStream os =checksumOutput.get(csIndex);
055                if (os!=null)
056                {
057                    os.write( cs.getChecksum( ).getBytes( ) );
058                }
059            }
060
061        } catch ( IOException e ) {
062
063        }
064    }
065}