| /* |
| * Copyright (c) 2015, 2016, Oracle and/or its affiliates. All rights reserved. |
| * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
| * |
| * This code is free software; you can redistribute it and/or modify it |
| * under the terms of the GNU General Public License version 2 only, as |
| * published by the Free Software Foundation. Oracle designates this |
| * particular file as subject to the "Classpath" exception as provided |
| * by Oracle in the LICENSE file that accompanied this code. |
| * |
| * This code is distributed in the hope that it will be useful, but WITHOUT |
| * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
| * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
| * version 2 for more details (a copy is included in the LICENSE file that |
| * accompanied this code). |
| * |
| * You should have received a copy of the GNU General Public License version |
| * 2 along with this work; if not, write to the Free Software Foundation, |
| * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
| * |
| * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
| * or visit www.oracle.com if you need additional information or have any |
| * questions. |
| */ |
| |
| package jdk.internal.module; |
| |
| import java.io.IOException; |
| import java.io.UncheckedIOException; |
| import java.nio.ByteBuffer; |
| import java.nio.channels.FileChannel; |
| import java.nio.file.Path; |
| import java.security.MessageDigest; |
| import java.security.NoSuchAlgorithmException; |
| import java.util.Collections; |
| import java.util.HashMap; |
| import java.util.Map; |
| import java.util.Objects; |
| import java.util.Set; |
| |
| /** |
| * The result of hashing the contents of a number of module artifacts. |
| */ |
| |
| public final class ModuleHashes { |
| |
| /** |
| * A supplier of a message digest. |
| */ |
| public static interface HashSupplier { |
| byte[] generate(String algorithm); |
| } |
| |
| private final String algorithm; |
| private final Map<String, byte[]> nameToHash; |
| |
| /** |
| * Creates a {@code ModuleHashes}. |
| * |
| * @param algorithm the algorithm used to create the hashes |
| * @param nameToHash the map of module name to hash value |
| */ |
| public ModuleHashes(String algorithm, Map<String, byte[]> nameToHash) { |
| this.algorithm = algorithm; |
| this.nameToHash = Collections.unmodifiableMap(nameToHash); |
| } |
| |
| /** |
| * Returns the algorithm used to hash the modules ("SHA-256" for example). |
| */ |
| public String algorithm() { |
| return algorithm; |
| } |
| |
| /** |
| * Returns the set of module names for which hashes are recorded. |
| */ |
| public Set<String> names() { |
| return nameToHash.keySet(); |
| } |
| |
| /** |
| * Returns the hash for the given module name, {@code null} |
| * if there is no hash recorded for the module. |
| */ |
| public byte[] hashFor(String mn) { |
| return nameToHash.get(mn); |
| } |
| |
| /** |
| * Returns unmodifiable map of module name to hash |
| */ |
| public Map<String, byte[]> hashes() { |
| return nameToHash; |
| } |
| |
| /** |
| * Computes the hash for the given file with the given message digest |
| * algorithm. |
| * |
| * @throws UncheckedIOException if an I/O error occurs |
| * @throws RuntimeException if the algorithm is not available |
| */ |
| public static byte[] computeHash(Path file, String algorithm) { |
| try { |
| MessageDigest md = MessageDigest.getInstance(algorithm); |
| |
| // Ideally we would just mmap the file but this consumes too much |
| // memory when jlink is running concurrently on very large jmods |
| try (FileChannel fc = FileChannel.open(file)) { |
| ByteBuffer bb = ByteBuffer.allocate(32*1024); |
| while (fc.read(bb) > 0) { |
| bb.flip(); |
| md.update(bb); |
| assert bb.remaining() == 0; |
| bb.clear(); |
| } |
| } |
| |
| return md.digest(); |
| } catch (NoSuchAlgorithmException e) { |
| throw new RuntimeException(e); |
| } catch (IOException ioe) { |
| throw new UncheckedIOException(ioe); |
| } |
| } |
| |
| /** |
| * Computes the hash for every entry in the given map, returning a |
| * {@code ModuleHashes} to encapsulate the result. The map key is |
| * the entry name, typically the module name. The map value is the file |
| * path to the entry (module artifact). |
| * |
| * @return ModuleHashes that encapsulates the hashes |
| */ |
| public static ModuleHashes generate(Map<String, Path> map, String algorithm) { |
| Map<String, byte[]> nameToHash = new HashMap<>(); |
| for (Map.Entry<String, Path> entry: map.entrySet()) { |
| String name = entry.getKey(); |
| Path path = entry.getValue(); |
| nameToHash.put(name, computeHash(path, algorithm)); |
| } |
| return new ModuleHashes(algorithm, nameToHash); |
| } |
| |
| /** |
| * This is used by jdk.internal.module.SystemModules class |
| * generated at link time. |
| */ |
| public static class Builder { |
| final String algorithm; |
| final Map<String, byte[]> nameToHash; |
| |
| Builder(String algorithm, int initialCapacity) { |
| this.nameToHash = new HashMap<>(initialCapacity); |
| this.algorithm = Objects.requireNonNull(algorithm); |
| } |
| |
| /** |
| * Sets the module hash for the given module name |
| */ |
| public Builder hashForModule(String mn, byte[] hash) { |
| nameToHash.put(mn, hash); |
| return this; |
| } |
| |
| /** |
| * Builds a {@code ModuleHashes}. |
| */ |
| public ModuleHashes build() { |
| if (!nameToHash.isEmpty()) { |
| return new ModuleHashes(algorithm, nameToHash); |
| } else { |
| return null; |
| } |
| } |
| } |
| } |