dev.responsive.kafka.internal.db.partitioning.Murmur3Hasher Maven / Gradle / Ivy
/*
* Copyright 2023 Responsive Computing, Inc.
*
* Licensed 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 dev.responsive.kafka.internal.db.partitioning;
import org.apache.kafka.common.utils.Bytes;
import org.apache.kafka.streams.state.internals.Murmur3;
public class Murmur3Hasher implements Hasher {
// ensure that the default sub-partitioning hasher is unlikely
// to be the same as the hasher that was used for the original
// partition scheme - if the hashers are the same, and the
// number of sub partitions is equal to the number of original
// partitions, all keys would be mapped to the same sub-partition
// and all other sub-partitions would be empty
static final int SALT = 31;
@Override
public Integer apply(final Bytes bytes) {
return SALT * Murmur3.hash32(bytes.get());
}
}