io.nosqlbench.virtdata.library.random.RandomRangedToLong Maven / Gradle / Ivy
/*
* Copyright (c) 2022 nosqlbench
*
* 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 io.nosqlbench.virtdata.library.random;
import io.nosqlbench.virtdata.api.annotations.DeprecatedFunction;
import org.apache.commons.math3.random.MersenneTwister;
import java.util.function.LongUnaryOperator;
@DeprecatedFunction("random mappers are not deterministic. They will be replaced with hash-based functions.")
public class RandomRangedToLong implements LongUnaryOperator {
private final MersenneTwister theTwister;
private final long min;
private final long max;
private final long length;
public RandomRangedToLong(long min, long max) {
this(min,max,System.nanoTime());
}
public RandomRangedToLong(long min, long max, long seed) {
this.theTwister = new MersenneTwister(seed);
if (max<=min) {
throw new RuntimeException("max must be >= min");
}
this.min = min;
this.max = max;
this.length = max - min;
}
@Override
public long applyAsLong(long input) {
long value = Math.abs(theTwister.nextLong());
value %= length;
value += min;
return value;
}
public String toString() {
return getClass().getSimpleName() + ":" + min + ":" + max;
}
}