/*
 * Copyright (c) 2013, 2019 Oracle and/or its affiliates. All rights reserved.
 *
 * This program and the accompanying materials are made available under the
 * terms of the Eclipse Public License v. 2.0, which is available at
 * http://www.eclipse.org/legal/epl-2.0.
 *
 * This Source Code may also be made available under the following Secondary
 * Licenses when the conditions for such availability set forth in the
 * Eclipse Public License v. 2.0 are satisfied: GNU General Public License,
 * version 2 with the GNU Classpath Exception, which is available at
 * https://www.gnu.org/software/classpath/license.html.
 *
 * SPDX-License-Identifier: EPL-2.0 OR GPL-2.0 WITH Classpath-exception-2.0
 */

package org.glassfish.jersey.server;

import java.lang.annotation.Documented;
import java.lang.annotation.ElementType;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.annotation.Target;

import javax.inject.Qualifier;

Injection qualifier that can be used to inject a ScheduledExecutorService instance used by Jersey to execute background timed/scheduled tasks. 
 A scheduled executor service instance injected using this injection qualifier can be customized by registering a custom ScheduledExecutorServiceProvider implementation that is itself annotated with the @BackgroundScheduler annotation. 

Typically, when facing a need to execute a scheduled background task, you would be creating a new
standalone executor service that would be using a new standalone thread pool. This would however break
the ability of Jersey to run in environments that have specific thread management and provisioning
requirements. In order to simplify and unify programming model for scheduling background tasks in
Jersey runtime, Jersey provides an this qualifier to inject a common, task scheduler that is properly
configured to support customizable runtime thread .

Author:
Marek Potociar
See Also:
BackgroundSchedulerLiteral
Since:
2.18/**
 * Injection qualifier that can be used to inject a {@link java.util.concurrent.ScheduledExecutorService}
 * instance used by Jersey to execute background timed/scheduled tasks.
 * <p>
 * A scheduled executor service instance injected using this injection qualifier can be customized by registering
 * a custom {@link org.glassfish.jersey.spi.ScheduledExecutorServiceProvider} implementation that is itself annotated
 * with the {@code &#64;BackgroundScheduler} annotation.
 * </p>
 * <p>
 * Typically, when facing a need to execute a scheduled background task, you would be creating a new
 * standalone executor service that would be using a new standalone thread pool. This would however break
 * the ability of Jersey to run in environments that have specific thread management and provisioning
 * requirements. In order to simplify and unify programming model for scheduling background tasks in
 * Jersey runtime, Jersey provides an this qualifier to inject a common, task scheduler that is properly
 * configured to support customizable runtime thread .
 * </p>
 *
 * @author Marek Potociar
 * @see BackgroundSchedulerLiteral
 * @since 2.18
 */
@Target({ElementType.PARAMETER, ElementType.FIELD, ElementType.METHOD, ElementType.TYPE})
@Retention(RetentionPolicy.RUNTIME)
@Documented
@Qualifier
public @interface BackgroundScheduler {

}