org.eclipse.aether.util.ChecksumUtils Maven / Gradle / Ivy
/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing,
* software distributed under the License is distributed on an
* "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
* KIND, either express or implied. See the License for the
* specific language governing permissions and limitations
* under the License.
*/
package org.eclipse.aether.util;
import java.io.BufferedReader;
import java.io.ByteArrayInputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.nio.charset.StandardCharsets;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
import java.util.Collection;
import java.util.LinkedHashMap;
import java.util.Map;
/**
* A utility class to assist in the verification and generation of checksums.
*/
public final class ChecksumUtils {
private ChecksumUtils() {
// hide constructor
}
/**
* Extracts the checksum from the specified file.
*
* @param checksumFile The path to the checksum file, must not be {@code null}.
* @return The checksum stored in the file, never {@code null}.
* @throws IOException If the checksum does not exist or could not be read for other reasons.
* @deprecated Use SPI FileProcessor to read and write checksum files.
*/
@Deprecated
public static String read(File checksumFile) throws IOException {
String checksum = "";
try (BufferedReader br = new BufferedReader(
new InputStreamReader(new FileInputStream(checksumFile), StandardCharsets.UTF_8), 512)) {
while (true) {
String line = br.readLine();
if (line == null) {
break;
}
line = line.trim();
if (line.length() > 0) {
checksum = line;
break;
}
}
}
if (checksum.matches(".+= [0-9A-Fa-f]+")) {
int lastSpacePos = checksum.lastIndexOf(' ');
checksum = checksum.substring(lastSpacePos + 1);
} else {
int spacePos = checksum.indexOf(' ');
if (spacePos != -1) {
checksum = checksum.substring(0, spacePos);
}
}
return checksum;
}
/**
* Calculates checksums for the specified file.
*
* @param dataFile The file for which to calculate checksums, must not be {@code null}.
* @param algos The names of checksum algorithms (cf. {@link MessageDigest#getInstance(String)} to use, must not be
* {@code null}.
* @return The calculated checksums, indexed by algorithm name, or the exception that occurred while trying to
* calculate it, never {@code null}.
* @throws IOException If the data file could not be read.
* @deprecated Use SPI checksum selector instead.
*/
@Deprecated
public static Map calc(File dataFile, Collection algos) throws IOException {
return calc(new FileInputStream(dataFile), algos);
}
/**
* @deprecated Use SPI checksum selector instead.
*/
@Deprecated
public static Map calc(byte[] dataBytes, Collection algos) throws IOException {
return calc(new ByteArrayInputStream(dataBytes), algos);
}
private static Map calc(InputStream data, Collection algos) throws IOException {
Map results = new LinkedHashMap<>();
Map digests = new LinkedHashMap<>();
for (String algo : algos) {
try {
digests.put(algo, MessageDigest.getInstance(algo));
} catch (NoSuchAlgorithmException e) {
results.put(algo, e);
}
}
try (InputStream in = data) {
for (byte[] buffer = new byte[32 * 1024]; ; ) {
int read = in.read(buffer);
if (read < 0) {
break;
}
for (MessageDigest digest : digests.values()) {
digest.update(buffer, 0, read);
}
}
}
for (Map.Entry entry : digests.entrySet()) {
byte[] bytes = entry.getValue().digest();
results.put(entry.getKey(), toHexString(bytes));
}
return results;
}
/**
* Creates a hexadecimal representation of the specified bytes. Each byte is converted into a two-digit hex number
* and appended to the result with no separator between consecutive bytes.
*
* @param bytes The bytes to represent in hex notation, may be be {@code null}.
* @return The hexadecimal representation of the input or {@code null} if the input was {@code null}.
*/
@SuppressWarnings("checkstyle:magicnumber")
public static String toHexString(byte[] bytes) {
if (bytes == null) {
return null;
}
StringBuilder buffer = new StringBuilder(bytes.length * 2);
for (byte aByte : bytes) {
int b = aByte & 0xFF;
if (b < 0x10) {
buffer.append('0');
}
buffer.append(Integer.toHexString(b));
}
return buffer.toString();
}
/**
* Creates a byte array out of hexadecimal representation of the specified bytes. If input string is {@code null},
* {@code null} is returned. Input value must have even length (due hex encoding = 2 chars one byte).
*
* @param hexString The hexString to convert to byte array, may be {@code null}.
* @return The byte array of the input or {@code null} if the input was {@code null}.
* @since 1.8.0
*/
@SuppressWarnings("checkstyle:magicnumber")
public static byte[] fromHexString(String hexString) {
if (hexString == null) {
return null;
}
if (hexString.isEmpty()) {
return new byte[] {};
}
int len = hexString.length();
if (len % 2 != 0) {
throw new IllegalArgumentException("hexString length not even");
}
byte[] data = new byte[len / 2];
for (int i = 0; i < len; i += 2) {
data[i / 2] = (byte)
((Character.digit(hexString.charAt(i), 16) << 4) + Character.digit(hexString.charAt(i + 1), 16));
}
return data;
}
}