org.apache.hadoop.hdfs.server.datanode.erasurecode.StripedBlockChecksumMd5CrcReconstructor 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.apache.hadoop.hdfs.server.datanode.erasurecode;
import java.io.IOException;
import java.security.MessageDigest;
import org.apache.hadoop.classification.InterfaceAudience;
import org.apache.hadoop.io.DataOutputBuffer;
import org.apache.hadoop.io.MD5Hash;
/**
* Computes running MD5-of-CRC over reconstructed chunk CRCs.
*/
@InterfaceAudience.Private
public class StripedBlockChecksumMd5CrcReconstructor
extends StripedBlockChecksumReconstructor {
private MD5Hash md5;
private MessageDigest digester;
public StripedBlockChecksumMd5CrcReconstructor(ErasureCodingWorker worker,
StripedReconstructionInfo stripedReconInfo,
DataOutputBuffer checksumWriter,
long requestedBlockLength) throws IOException {
super(worker, stripedReconInfo, checksumWriter, requestedBlockLength);
}
@Override
public Object getDigestObject() {
return md5;
}
@Override
void prepareDigester() throws IOException {
digester = MD5Hash.getDigester();
}
@Override
void updateDigester(byte[] checksumBytes, int dataBytesPerChecksum)
throws IOException {
if (digester == null) {
throw new IOException(String.format(
"Called updatedDigester with checksumBytes.length=%d, "
+ "dataBytesPerChecksum=%d but digester is null",
checksumBytes.length, dataBytesPerChecksum));
}
digester.update(checksumBytes, 0, checksumBytes.length);
}
@Override
void commitDigest() throws IOException {
if (digester == null) {
throw new IOException("Called commitDigest() but digester is null");
}
byte[] digest = digester.digest();
md5 = new MD5Hash(digest);
md5.write(getChecksumWriter());
}
}