001/* 002 * Licensed to the Apache Software Foundation (ASF) under one 003 * or more contributor license agreements. See the NOTICE file 004 * distributed with this work for additional information 005 * regarding copyright ownership. The ASF licenses this file 006 * to you under the Apache License, Version 2.0 (the 007 * "License"); you may not use this file except in compliance 008 * with the License. You may obtain a copy of the License at 009 * 010 * http://www.apache.org/licenses/LICENSE-2.0 011 * 012 * Unless required by applicable law or agreed to in writing, 013 * software distributed under the License is distributed on an 014 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY 015 * KIND, either express or implied. See the License for the 016 * specific language governing permissions and limitations 017 * under the License. 018 */ 019package org.eclipse.aether.internal.impl.checksum; 020 021import java.nio.ByteBuffer; 022import java.security.MessageDigest; 023import java.security.NoSuchAlgorithmException; 024 025import org.eclipse.aether.spi.connector.checksum.ChecksumAlgorithm; 026import org.eclipse.aether.spi.connector.checksum.ChecksumAlgorithmFactory; 027import org.eclipse.aether.spi.connector.checksum.ChecksumAlgorithmFactorySupport; 028import org.eclipse.aether.util.StringDigestUtil; 029 030/** 031 * Support class to implement {@link ChecksumAlgorithmFactory} based on Java {@link MessageDigest}. 032 * 033 * @since 1.8.0 034 */ 035public abstract class MessageDigestChecksumAlgorithmFactorySupport extends ChecksumAlgorithmFactorySupport { 036 public MessageDigestChecksumAlgorithmFactorySupport(String name, String extension) { 037 super(name, extension); 038 } 039 040 @Override 041 public ChecksumAlgorithm getAlgorithm() { 042 try { 043 MessageDigest messageDigest = MessageDigest.getInstance(getName()); 044 return new ChecksumAlgorithm() { 045 @Override 046 public void update(final ByteBuffer input) { 047 messageDigest.update(input); 048 } 049 050 @Override 051 public String checksum() { 052 return StringDigestUtil.toHexString(messageDigest.digest()); 053 } 054 }; 055 } catch (NoSuchAlgorithmException e) { 056 throw new IllegalStateException( 057 "MessageDigest algorithm " + getName() + " not supported, but is required by resolver.", e); 058 } 059 } 060}