/*
* 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.flink.graph.generator.random;
import org.apache.commons.math3.random.RandomGenerator;
import java.util.List;
/**
* A {@code RandomGenerableFactory} returns a scale-free collection of sources
* of pseudorandomness which can be used to perform repeatable parallel
* computation regardless of parallelism.
*
* <pre>
* {@code
* RandomGenerableFactory<JDKRandomGenerator> factory = new JDKRandomGeneratorFactory()
*
* List<BlockInfo<T>> generatorBlocks = factory
* .getRandomGenerables(elementCount, cyclesPerElement);
*
* DataSet<...> generatedEdges = env
* .fromCollection(generatorBlocks)
* .name("Random generators")
* .flatMap(...
* }
* </pre>
*
* @param <T> the type of the {@code RandomGenerator}
*/
public interface RandomGenerableFactory<T extends RandomGenerator> {
/**
* The amount of work ({@code elementCount * cyclerPerElement}) is used to
* generate a list of blocks of work of near-equal size.
*
* @param elementCount number of elements, as indexed in the {@code BlockInfo}
* @param cyclesPerElement number of cycles of the PRNG per element
* @return the list of configuration blocks
*/
List<BlockInfo<T>> getRandomGenerables(long elementCount, int cyclesPerElement);
}