Java tutorial
/** * The MIT License * * Copyright (C) 2007 Asterios Raptis * * Permission is hereby granted, free of charge, to any person obtaining * a copy of this software and associated documentation files (the * "Software"), to deal in the Software without restriction, including * without limitation the rights to use, copy, modify, merge, publish, * distribute, sublicense, and/or sell copies of the Software, and to * permit persons to whom the Software is furnished to do so, subject to * the following conditions: * * The above copyright notice and this permission notice shall be * included in all copies or substantial portions of the Software. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */ package de.alpharogroup.file.checksum; import java.io.File; import java.io.FileInputStream; import java.io.FileNotFoundException; import java.io.IOException; import java.security.MessageDigest; import java.security.NoSuchAlgorithmException; import java.util.zip.Adler32; import java.util.zip.CRC32; import java.util.zip.CheckedInputStream; import java.util.zip.Checksum; import org.apache.commons.lang.ArrayUtils; import org.apache.log4j.Logger; import de.alpharogroup.file.read.ReadFileExtensions; import de.alpharogroup.io.StreamExtensions; /** * The class {@link ChecksumExtensions} is a utility class for computing checksum from files and byte arrays. * * @version 1.0 * @author Asterios Raptis */ public final class ChecksumExtensions { /** The LOGGER. */ protected static final Logger LOGGER = Logger.getLogger(ChecksumExtensions.class.getName()); /** * Utility method for tests. * * @param data * the byte array * * @throws NoSuchAlgorithmException * the no such algorithm exception */ private static void checkWithByteArray(final byte[] data) throws NoSuchAlgorithmException { final Algorithm[] algorithms = Algorithm.values(); for (final Algorithm algorithm : algorithms) { try { final String result = getChecksum(data, algorithm.getAlgorithm()); LOGGER.info("getChecksum from " + algorithm + " algorithm:\t\t" + result); } catch (final NoSuchAlgorithmException e) { // do nothing } } } /** * Utility method for tests. * * @param pom * the pom * * @throws NoSuchAlgorithmException * Is thrown if the algorithm is not supported or does not exists. */ private static void checkWithFile(final File pom) throws NoSuchAlgorithmException { final Algorithm[] algorithms = Algorithm.values(); for (final Algorithm algorithm : algorithms) { try { final String result = getChecksum(pom, algorithm.getAlgorithm()); LOGGER.info("getChecksum from " + algorithm + " algorithm:\t\t" + result); } catch (final NoSuchAlgorithmException e) { // do nothing } } } /** * Gets the checksum from the given byte array with an instance of. * * @param bytes * the byte array. * @param algorithm * the algorithm to get the checksum. This could be for instance "MD4", "MD5", * "SHA-1", "SHA-256", "SHA-384" or "SHA-512". * @return The checksum from the file as a String object. * @throws NoSuchAlgorithmException * Is thrown if the algorithm is not supported or does not exists. * {@link java.security.MessageDigest} object. */ public static String getChecksum(final byte[] bytes, final Algorithm algorithm) throws NoSuchAlgorithmException { return getChecksum(bytes, algorithm.getAlgorithm()); } /** * Gets the checksum from the given byte array with an instance of. * * @param bytes * the byte array. * @param algorithm * the algorithm to get the checksum. This could be for instance "MD4", "MD5", * "SHA-1", "SHA-256", "SHA-384" or "SHA-512". * @return The checksum from the file as a String object. * @throws NoSuchAlgorithmException * Is thrown if the algorithm is not supported or does not exists. * {@link java.security.MessageDigest} object. */ public static String getChecksum(final byte[] bytes, final String algorithm) throws NoSuchAlgorithmException { final MessageDigest messageDigest = MessageDigest.getInstance(algorithm); messageDigest.reset(); messageDigest.update(bytes); final byte digest[] = messageDigest.digest(); final StringBuilder hexView = new StringBuilder(); for (final byte element : digest) { final String intAsHex = Integer.toHexString(0xFF & element); if (intAsHex.length() == 1) { hexView.append('0'); } hexView.append(intAsHex); } return hexView.toString(); } /** * Gets the checksum from the given byte array with an instance of. * * @param bytes * the Byte object array. * @param algorithm * the algorithm to get the checksum. This could be for instance "MD4", "MD5", * "SHA-1", "SHA-256", "SHA-384" or "SHA-512". * @return The checksum from the file as a String object. * @throws NoSuchAlgorithmException * Is thrown if the algorithm is not supported or does not exists. * {@link java.security.MessageDigest} object. */ public static String getChecksum(final Byte[] bytes, final Algorithm algorithm) throws NoSuchAlgorithmException { return getChecksum(bytes, algorithm.getAlgorithm()); } /** * Gets the checksum from the given byte array with an instance of. * * @param bytes * the Byte object array. * @param algorithm * the algorithm to get the checksum. This could be for instance "MD4", "MD5", * "SHA-1", "SHA-256", "SHA-384" or "SHA-512". * @return The checksum from the file as a String object. * @throws NoSuchAlgorithmException * Is thrown if the algorithm is not supported or does not exists. * {@link java.security.MessageDigest} object. */ public static String getChecksum(final Byte[] bytes, final String algorithm) throws NoSuchAlgorithmException { return getChecksum(ArrayUtils.toPrimitive(bytes), algorithm); } /** * Gets the checksum from the given file with an instance of the given algorithm. * * @param file * the file. * @param algorithm * the algorithm to get the checksum. This could be for instance "MD4", "MD5", * "SHA-1", "SHA-256", "SHA-384" or "SHA-512". * @return The checksum from the file as a String object. * @throws NoSuchAlgorithmException * Is thrown if the algorithm is not supported or does not exists. * {@link java.security.MessageDigest} object. */ public static String getChecksum(final File file, final Algorithm algorithm) throws NoSuchAlgorithmException { return getChecksum(file, algorithm.getAlgorithm()); } /** * Gets the checksum from the given file. If the flag crc is true than the CheckedInputStream is * constructed with an instance of <code>java.util.zip.CRC32</code> otherwise with an instance * of <code>java.util.zip.Adler32</code>. * * @param file * The file The file from what to get the checksum. * @param crc * The crc If the flag crc is true than the CheckedInputStream is constructed with an * instance of {@link java.util.zip.CRC32} object otherwise it is constructed with an * instance of * @return The checksum from the given file as long. * @throws FileNotFoundException * Is thrown if the file is not found. * @throws IOException * Signals that an I/O exception has occurred. {@link java.util.zip.CRC32} object * otherwise it is constructed with an instance of {@link java.util.zip.Adler32} * object. {@link java.util.zip.Adler32} object. */ public static long getChecksum(final File file, final boolean crc) throws FileNotFoundException, IOException { CheckedInputStream cis = null; if (crc) { cis = new CheckedInputStream(new FileInputStream(file), new CRC32()); } else { cis = new CheckedInputStream(new FileInputStream(file), new Adler32()); } final int length = (int) file.length(); final byte[] buffer = new byte[length]; long checksum = 0; while (cis.read(buffer) >= 0) { checksum = cis.getChecksum().getValue(); } checksum = cis.getChecksum().getValue(); StreamExtensions.closeInputStream(cis); return checksum; } /** * Gets the checksum from the given file with an instance of the given algorithm. * * @param file * the file. * @param algorithm * the algorithm to get the checksum. This could be for instance "MD4", "MD5", * "SHA-1", "SHA-256", "SHA-384" or "SHA-512". * @return The checksum from the file as a String object. * @throws NoSuchAlgorithmException * Is thrown if the algorithm is not supported or does not exists. * {@link java.security.MessageDigest} object. */ public static String getChecksum(final File file, final String algorithm) throws NoSuchAlgorithmException { return getChecksum(ReadFileExtensions.toByteArray(file), algorithm); } /** * Gets the checksum from the given byte array with an instance of. * * @param bytes * The byte array. * @return The checksum from the byte array as long. {@link java.util.zip.Adler32} object. */ public static long getCheckSumAdler32(final byte[] bytes) { final Checksum checksum = new Adler32(); checksum.update(bytes, 0, bytes.length); final long cs = checksum.getValue(); return cs; } /** * Gets the checksum from the given file with an instance of. * * @param file * The file. * @return The checksum from the file as long. {@link java.util.zip.Adler32} object. */ public static long getCheckSumAdler32(final File file) { return getCheckSumAdler32(ReadFileExtensions.toByteArray(file)); } /** * Gets the checksum from the given byte array with an instance of. * * @param bytes * The byte array. * @return The checksum from the byte array as long. {@link java.util.zip.CRC32} object. */ public static long getCheckSumCRC32(final byte[] bytes) { final Checksum checksum = new CRC32(); checksum.update(bytes, 0, bytes.length); final long cs = checksum.getValue(); return cs; } /** * Gets the checksum from the given file with an instance of. * * @param file * The file. * @return The checksum from the file as long. {@link java.util.zip.CRC32} object. */ public static long getCheckSumCRC32(final File file) { return getCheckSumCRC32(ReadFileExtensions.toByteArray(file)); } /** * Gets the checksum quietly from the given byte array with an instance of. * * @param bytes * the byte array. * @param algorithm * the algorithm to get the checksum. This could be for instance "MD4", "MD5", * "SHA-1", "SHA-256", "SHA-384" or "SHA-512". * @return The checksum from the file as a String object. */ public static String getChecksumQuietly(final byte[] bytes, final Algorithm algorithm) { try { return getChecksum(bytes, algorithm.getAlgorithm()); } catch (final NoSuchAlgorithmException e) { LOGGER.error("getChecksumQuietly failed...\n" + e.getMessage(), e); } return null; } /** * Gets the checksum quietly from the given byte array with an instance of. * * @param bytes * the byte array. * @param algorithm * the algorithm to get the checksum. This could be for instance "MD4", "MD5", * "SHA-1", "SHA-256", "SHA-384" or "SHA-512". * @return The checksum from the file as a String object. */ public static String getChecksumQuietly(final byte[] bytes, final String algorithm) { try { return getChecksum(bytes, algorithm); } catch (final NoSuchAlgorithmException e) { LOGGER.error("getChecksumQuietly failed...\n" + e.getMessage(), e); } return algorithm; } /** * Gets the checksum quietly from the given byte array with an instance of. * * @param bytes * the Byte object array. * @param algorithm * the algorithm to get the checksum. This could be for instance "MD4", "MD5", * "SHA-1", "SHA-256", "SHA-384" or "SHA-512". * @return The checksum from the file as a String object. */ public static String getChecksumQuietly(final Byte[] bytes, final String algorithm) { try { return getChecksum(bytes, algorithm); } catch (final NoSuchAlgorithmException e) { LOGGER.error("getChecksumQuietly failed...\n" + e.getMessage(), e); } return algorithm; } /** * Gets the checksum quietly from the given file with an instance of the given algorithm. * * @param file * the file. * @param algorithm * the algorithm to get the checksum. This could be for instance "MD4", "MD5", * "SHA-1", "SHA-256", "SHA-384" or "SHA-512". * @return The checksum from the file as a String object or null if a NoSuchAlgorithmException * will be thrown. exists. {@link java.security.MessageDigest} object. */ public static String getChecksumQuietly(final File file, final Algorithm algorithm) { try { return getChecksum(file, algorithm.getAlgorithm()); } catch (final NoSuchAlgorithmException e) { LOGGER.error("getChecksumQuietly failed...\n" + e.getMessage(), e); } return null; } /** * The main method. * * @param args * The args * @throws FileNotFoundException * Is thrown if the file is not found. * @throws IOException * Signals that an I/O exception has occurred. * @throws NoSuchAlgorithmException * Is thrown if the algorithm is not supported or does not exists. */ public static void main(final String[] args) throws FileNotFoundException, IOException, NoSuchAlgorithmException { if (args.length != 1) { System.err.println("Usage: java ChecksumCRC32 filename"); } else { final File pom = new File(args[0]); checkWithFile(pom); long checksum = getChecksum(new File(args[0]), true); System.out.println("CRC32 checksum:" + checksum); checksum = getChecksum(new File(args[0]), false); System.out.println("Adler32 checksum:" + checksum); final byte[] ba = ReadFileExtensions.readFileToBytearray(pom); checkWithByteArray(ba); } } /** * Private constructor. */ private ChecksumExtensions() { } }