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/*
 * Copyright (c) 2012-2024, jcabi.com
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met: 1) Redistributions of source code must retain the above
 * copyright notice, this list of conditions and the following
 * disclaimer. 2) Redistributions in binary form must reproduce the above
 * copyright notice, this list of conditions and the following
 * disclaimer in the documentation and/or other materials provided
 * with the distribution. 3) Neither the name of the jcabi.com nor
 * the names of its contributors may be used to endorse or promote
 * products derived from this software without specific prior written
 * permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT
 * NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
 * FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
 * THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
 * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
 * OF THE POSSIBILITY OF SUCH DAMAGE.
 */
package com.jcabi.aspects;

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 java.util.concurrent.TimeUnit;

/**
 * Schedules the method to run with fixed delay, automatically.
 *
 * For example, you want a method to do something every minute:
 *
 * 
 @ScheduleWithFixedDelay(delay = 1, unit = TimeUnit.MINUTES)
 * public class Bucket implements Runnable, Closeable {
 *   @Override
 *   void run() {
 *     // do some routine job
 *   }
 *   @Override
 *   void close() {
 *     // close operations
 *   }
 * }
 *
 * Execution will be started as soon as you make an instance of the class,
 * and will be stopped when you call {@code close()}:
 *
 * 
 Bucket bucket = new Bucket();
 * // some time later
 * bucket.close();
 *
 * In order to be executed the class should implement either
 * {@link Runnable} or {@link java.util.concurrent.Callable}. In order to
 * be closed and stopped, your the class should implement
 * {@link java.io.Closeable} and its {@code close()}
 * method should be explicitly called
 * at the moment you want it to stop.
 *
 * NOTE: It should be pointed out that in order to ensure that there
 * are no duplicate executions, you can only schedule an execution once between
 * all equal objects (i.e. instances that are equal as per
 * {@link Object#equals(Object)})). Invoking the same method multiple times,
 * without stopping it first, will result in an {@link IllegalStateException}
 * being thrown.
 *
 * @since 0.7.16
 * @see http://aspects.jcabi.com/
 */
@Documented
@Retention(RetentionPolicy.RUNTIME)
@Target(ElementType.TYPE)
public @interface ScheduleWithFixedDelay {

    /**
     * Delay, in time units.
     * @return The delay time amount
     */
    int delay() default 1;

    /**
     * Time units of delay.
     * @return The time unit
     */
    TimeUnit unit() default TimeUnit.MINUTES;

    /**
     * How long to wait for the task to finish after shutdown in await units.
     *
     * @return The await time amount
     */
    int await() default 1;

    /**
     * Time units of await time.
     * @return The await time unit
     */
    TimeUnit awaitUnit() default TimeUnit.MINUTES;

    /**
     * How many times to do a forceful shutdown after await time.
     * Each forceful shutdown attempt will be followed by a 1 second wait to
     * allow the threads to finish.
     * @return The number if times
     */
    int shutdownAttempts() default 1;

    /**
     * Total number of fixed threads.
     * @return The number of threads
     */
    int threads() default 1;

    /**
     * Be less verbose.
     * @return The flag
     */
    boolean verbose() default true;
}