org.apache.hudi.common.util.hash.HashID Maven / Gradle / Ivy
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* 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.hudi.common.util.hash;
import net.jpountz.xxhash.XXHash32;
import net.jpountz.xxhash.XXHash64;
import net.jpountz.xxhash.XXHashFactory;
import org.apache.hadoop.hbase.util.Bytes;
import org.apache.hudi.exception.HoodieIOException;
import java.io.Serializable;
import java.nio.charset.StandardCharsets;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
/**
* A stateless Hash class which generates ID for the desired bit count.
*/
public class HashID implements Serializable {
private static final String MD5_ALGORITHM_NAME = "MD5";
private static final int HASH_SEED = 0xdabadaba;
/**
* Represents HashID size in bits.
*/
public enum Size {
BITS_32(32),
BITS_64(64),
BITS_128(128);
private final int bits;
Size(int bitCount) {
this.bits = bitCount;
}
/**
* Get this Hash size in bytes.
*
* @return Bytes needed to represent this size
*/
public int byteSize() {
return (((this.bits - 1) / Byte.SIZE) + 1);
}
/**
* Get this Hash size in bits.
*
* @return bits needed to represent the size
*/
public int bits() {
return this.bits;
}
@Override
public String toString() {
return "HashSize{" + bits + "}";
}
}
/**
* Get the hash value for a string message and for the desired @{@link Size}.
*
* @param message - String message to get the hash value for
* @param bits - @{@link Size} of the hash value
* @return Hash value for the message as byte array
*/
public static byte[] hash(final String message, final Size bits) {
return hash(message.getBytes(StandardCharsets.UTF_8), bits);
}
/**
* Get the hash value for a byte array and for the desired @{@link Size}.
*
* @param messageBytes - Byte array message to get the hash value for
* @param bits - @{@link Size} of the hash value
* @return Hash value for the message as byte array
*/
public static byte[] hash(final byte[] messageBytes, final Size bits) {
switch (bits) {
case BITS_32:
case BITS_64:
return getXXHash(messageBytes, bits);
case BITS_128:
return getMD5Hash(messageBytes);
default:
throw new IllegalArgumentException("Unexpected Hash size bits: " + bits);
}
}
public static int getXXHash32(final String message, int hashSeed) {
return getXXHash32(message.getBytes(StandardCharsets.UTF_8), hashSeed);
}
public static int getXXHash32(final byte[] message, int hashSeed) {
XXHashFactory factory = XXHashFactory.fastestInstance();
return factory.hash32().hash(message, 0, message.length, hashSeed);
}
private static byte[] getXXHash(final byte[] message, final Size bits) {
XXHashFactory factory = XXHashFactory.fastestInstance();
switch (bits) {
case BITS_32:
XXHash32 hash32 = factory.hash32();
return Bytes.toBytes(hash32.hash(message, 0, message.length, HASH_SEED));
case BITS_64:
XXHash64 hash64 = factory.hash64();
return Bytes.toBytes(hash64.hash(message, 0, message.length, HASH_SEED));
default:
throw new HoodieIOException("XX" + bits + " hash is unsupported!");
}
}
private static byte[] getMD5Hash(final byte[] message) throws HoodieIOException {
try {
MessageDigest messageDigest = MessageDigest.getInstance(MD5_ALGORITHM_NAME);
messageDigest.update(message);
return messageDigest.digest();
} catch (NoSuchAlgorithmException e) {
throw new HoodieIOException("Failed to create MD5 Hash: " + e);
}
}
}