code: /*
   * Copyright (c) 2016-present, RxJava Contributors.
   *
   * 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.reactivex.rxjava3.internal.schedulers;
  
  import io.reactivex.rxjava3.annotations.NonNull;
  import io.reactivex.rxjava3.core.Scheduler;
  
  /**
   * Allows retrieving multiple workers from the implementing
   * {@link io.reactivex.rxjava3.core.Scheduler} in a way that when asking for
   * at most the parallelism level of the Scheduler, those
   * {@link io.reactivex.rxjava3.core.Scheduler.Worker} instances will be running
   * with different backing threads.
   * <p>History: 2.1.8 - experimental
   * @since 2.2
   */
  public interface SchedulerMultiWorkerSupport {
  
      /**
       * Creates the given number of {@link io.reactivex.rxjava3.core.Scheduler.Worker} instances
       * that are possibly backed by distinct threads
       * and calls the specified {@code Consumer} with them.
       * @param number the number of workers to create, positive
       * @param callback the callback to send worker instances to
       */
      void createWorkers(int number, @NonNull WorkerCallback callback);
  
      /**
       * The callback interface for the {@link SchedulerMultiWorkerSupport#createWorkers(int, WorkerCallback)}
       * method.
       */
      interface WorkerCallback {
          /**
           * Called with the Worker index and instance.
           * @param index the worker index, zero-based
           * @param worker the worker instance
           */
          void onWorker(int index, @NonNull Scheduler.Worker worker);
      }
  }
  