001/* 002 * SonarQube 003 * Copyright (C) 2009-2017 SonarSource SA 004 * mailto:info AT sonarsource DOT com 005 * 006 * This program is free software; you can redistribute it and/or 007 * modify it under the terms of the GNU Lesser General Public 008 * License as published by the Free Software Foundation; either 009 * version 3 of the License, or (at your option) any later version. 010 * 011 * This program is distributed in the hope that it will be useful, 012 * but WITHOUT ANY WARRANTY; without even the implied warranty of 013 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 014 * Lesser General Public License for more details. 015 * 016 * You should have received a copy of the GNU Lesser General Public License 017 * along with this program; if not, write to the Free Software Foundation, 018 * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. 019 */ 020package org.sonar.api.batch.fs.internal.charhandler; 021 022import java.nio.ByteBuffer; 023import java.nio.CharBuffer; 024import java.nio.charset.CharacterCodingException; 025import java.nio.charset.CharsetEncoder; 026import java.nio.charset.CodingErrorAction; 027import java.nio.charset.StandardCharsets; 028import java.security.MessageDigest; 029 030import javax.annotation.CheckForNull; 031 032import org.apache.commons.codec.binary.Hex; 033import org.apache.commons.codec.digest.DigestUtils; 034 035public class FileHashComputer extends CharHandler { 036 private static final char LINE_FEED = '\n'; 037 038 039 private MessageDigest globalMd5Digest = DigestUtils.getMd5Digest(); 040 private StringBuilder sb = new StringBuilder(); 041 private final CharsetEncoder encoder; 042 private final String filePath; 043 044 public FileHashComputer(String filePath) { 045 encoder = StandardCharsets.UTF_8.newEncoder() 046 .onMalformedInput(CodingErrorAction.REPLACE) 047 .onUnmappableCharacter(CodingErrorAction.REPLACE); 048 this.filePath = filePath; 049 } 050 051 @Override 052 public void handleIgnoreEoL(char c) { 053 sb.append(c); 054 } 055 056 @Override 057 public void newLine() { 058 sb.append(LINE_FEED); 059 processBuffer(); 060 sb.setLength(0); 061 } 062 063 @Override 064 public void eof() { 065 if (sb.length() > 0) { 066 processBuffer(); 067 } 068 } 069 070 private void processBuffer() { 071 try { 072 if (sb.length() > 0) { 073 ByteBuffer encoded = encoder.encode(CharBuffer.wrap(sb)); 074 globalMd5Digest.update(encoded.array(), 0, encoded.limit()); 075 } 076 } catch (CharacterCodingException e) { 077 throw new IllegalStateException("Error encoding line hash in file: " + filePath, e); 078 } 079 } 080 081 @CheckForNull 082 public String getHash() { 083 return Hex.encodeHexString(globalMd5Digest.digest()); 084 } 085}