001package org.eclipse.aether.internal.impl.checksum; 002 003/* 004 * Licensed to the Apache Software Foundation (ASF) under one 005 * or more contributor license agreements. See the NOTICE file 006 * distributed with this work for additional information 007 * regarding copyright ownership. The ASF licenses this file 008 * to you under the Apache License, Version 2.0 (the 009 * "License"); you may not use this file except in compliance 010 * with the License. You may obtain a copy of the License at 011 * 012 * http://www.apache.org/licenses/LICENSE-2.0 013 * 014 * Unless required by applicable law or agreed to in writing, 015 * software distributed under the License is distributed on an 016 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY 017 * KIND, either express or implied. See the License for the 018 * specific language governing permissions and limitations 019 * under the License. 020 */ 021 022import org.eclipse.aether.spi.connector.checksum.ChecksumAlgorithm; 023import org.eclipse.aether.spi.connector.checksum.ChecksumAlgorithmFactory; 024import org.eclipse.aether.spi.connector.checksum.ChecksumAlgorithmFactorySupport; 025import org.eclipse.aether.util.ChecksumUtils; 026 027import java.nio.ByteBuffer; 028import java.security.MessageDigest; 029import java.security.NoSuchAlgorithmException; 030 031/** 032 * Support class to implement {@link ChecksumAlgorithmFactory} based on Java {@link MessageDigest}. 033 * 034 * @since 1.8.0 035 */ 036public abstract class MessageDigestChecksumAlgorithmFactorySupport 037 extends ChecksumAlgorithmFactorySupport 038{ 039 public MessageDigestChecksumAlgorithmFactorySupport( String name, String extension ) 040 { 041 super( name, extension ); 042 } 043 044 @Override 045 public ChecksumAlgorithm getAlgorithm() 046 { 047 try 048 { 049 MessageDigest messageDigest = MessageDigest.getInstance( getName() ); 050 return new ChecksumAlgorithm() 051 { 052 @Override 053 public void update( final ByteBuffer input ) 054 { 055 messageDigest.update( input ); 056 } 057 058 @Override 059 public String checksum() 060 { 061 return ChecksumUtils.toHexString( messageDigest.digest() ); 062 } 063 }; 064 } 065 catch ( NoSuchAlgorithmException e ) 066 { 067 throw new IllegalStateException( 068 "MessageDigest algorithm " + getName() + " not supported, but is required by resolver.", e ); 069 } 070 } 071}