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/* * Copyright 2002-2018 the original author or authors. * * 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 * * https://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.springframework.scheduling; import org.springframework.core.task.AsyncTaskExecutor; /** * A {@link org.springframework.core.task.TaskExecutor} extension exposing * scheduling characteristics that are relevant to potential task submitters. * * <p>Scheduling clients are encouraged to submit * {@link Runnable Runnables} that match the exposed preferences * of the {@code TaskExecutor} implementation in use. * * <p>Note: {@link SchedulingTaskExecutor} implementations are encouraged to also * implement the {@link org.springframework.core.task.AsyncListenableTaskExecutor} * interface. This is not required due to the dependency on Spring 4.0's new * {@link org.springframework.util.concurrent.ListenableFuture} interface, * which would make it impossible for third-party executor implementations * to remain compatible with both Spring 4.0 and Spring 3.x. * * @author Juergen Hoeller * @since 2.0 * @see SchedulingAwareRunnable * @see org.springframework.core.task.TaskExecutor * @see org.springframework.scheduling.commonj.WorkManagerTaskExecutor */ public interface SchedulingTaskExecutor extends AsyncTaskExecutor { /** * Does this {@code TaskExecutor} prefer short-lived tasks over long-lived tasks? * <p>A {@code SchedulingTaskExecutor} implementation can indicate whether it * prefers submitted tasks to perform as little work as they can within a single * task execution. For example, submitted tasks might break a repeated loop into * individual subtasks which submit a follow-up task afterwards (if feasible). * <p>This should be considered a hint. Of course {@code TaskExecutor} clients * are free to ignore this flag and hence the {@code SchedulingTaskExecutor} * interface overall. However, thread pools will usually indicated a preference * for short-lived tasks, allowing for more fine-grained scheduling. * @return {@code true} if this executor prefers short-lived tasks (the default), * {@code false} otherwise (for treatment like a regular {@code TaskExecutor}) */ default boolean prefersShortLivedTasks() { return true; } }