org.springframework.scheduling.SchedulingAwareRunnable Maven / Gradle / Ivy
/*
* Copyright 2002-2023 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.lang.Nullable;
/**
* Extension of the {@link Runnable} interface, adding special callbacks
* for long-running operations.
*
* Scheduling-capable TaskExecutors are encouraged to check a submitted
* Runnable, detecting whether this interface is implemented and reacting
* as appropriately as they are able to.
*
* @author Juergen Hoeller
* @since 2.0
* @see org.springframework.core.task.TaskExecutor
* @see SchedulingTaskExecutor
*/
public interface SchedulingAwareRunnable extends Runnable {
/**
* Return whether the Runnable's operation is long-lived
* ({@code true}) versus short-lived ({@code false}).
*
In the former case, the task will not allocate a thread from the thread
* pool (if any) but rather be considered as long-running background thread.
*
This should be considered a hint. Of course TaskExecutor implementations
* are free to ignore this flag and the SchedulingAwareRunnable interface overall.
*
The default implementation returns {@code false}, as of 6.1.
*/
default boolean isLongLived() {
return false;
}
/**
* Return a qualifier associated with this Runnable.
*
The default implementation returns {@code null}.
*
May be used for custom purposes depending on the scheduler implementation.
* {@link org.springframework.scheduling.config.TaskSchedulerRouter} introspects
* this qualifier in order to determine the target scheduler to be used
* for a given Runnable, matching the qualifier value (or the bean name)
* of a specific {@link org.springframework.scheduling.TaskScheduler} or
* {@link java.util.concurrent.ScheduledExecutorService} bean definition.
* @since 6.1
* @see org.springframework.scheduling.annotation.Scheduled#scheduler()
*/
@Nullable
default String getQualifier() {
return null;
}
}