org.redisson.api.RSemaphoreRx Maven / Gradle / Ivy

Go to download
Show more of this group Show more artifacts with this name
Show all versions of redisson Show documentation
Redis Java client with features of In-Memory Data Grid
There is a newer version: 3.39.0
/**
 * Copyright (c) 2013-2024 Nikita Koksharov
 *
 * 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 org.redisson.api;

import io.reactivex.rxjava3.core.Completable;
import io.reactivex.rxjava3.core.Single;

import java.time.Duration;
import java.util.concurrent.TimeUnit;

/**
 * RxJava2 interface of Redis based {@link java.util.concurrent.Semaphore}.
 * 
 * Works in non-fair mode. Therefore order of acquiring is unpredictable.
 *
 * @author Nikita Koksharov
 *
 */
public interface RSemaphoreRx extends RExpirableRx {

    /**
     * Acquires a permit.
     * Waits if necessary until a permit became available.
     *
     * @return true if a permit was acquired and false
     *         otherwise
     */
    Single tryAcquire();
    
    /**
     * Tries to acquire defined amount of currently available permits.
     *
     * @param permits the number of permits to acquire
     * @return true if permits were acquired and false
     *         otherwise
     */
    Single tryAcquire(int permits);

    /**
     * Acquires a permit.
     * Waits if necessary until a permit became available.
     * 
     * @return void
     *
     */
    Completable acquire();

    /**
     * Acquires defined amount of permits.
     * Waits if necessary until all permits became available.
     *
     * @param permits the number of permits to acquire
     * @throws IllegalArgumentException if permits is negative
     * @return void
     */
    Completable acquire(int permits);

    /**
     * Releases a permit.
     *
     * @return void
     */
    Completable release();

    /**
     * Releases defined amount of permits.
     *
     * @param permits amount
     * @return void
     */
    Completable release(int permits);

    /**
     * Tries to set number of permits.
     *
     * @param permits - number of permits
     * @return true if permits has been set successfully, otherwise false.  
     */
    Single trySetPermits(int permits);

    /**
     * Tries to set number of permits with defined time to live.
     *
     * @param timeToLive time to live
     * @param permits number of permits
     * @return true if permits has been set successfully, otherwise false.
     */
    Single trySetPermits(int permits, Duration timeToLive);

    /**
     * Use {@link #tryAcquire(Duration)} instead
     *
     * @param waitTime the maximum time to wait
     * @param unit the time unit
     * @return true if a permit was acquired and false
     *         otherwise
     */
    @Deprecated
    Single tryAcquire(long waitTime, TimeUnit unit);
    
    /**
     * Tries to acquire currently available permit.
     * Waits up to defined waitTime if necessary until a permit became available.
     *
     * @param waitTime the maximum time to wait
     * @return true if a permit was acquired and false
     *         otherwise
     */
    Single tryAcquire(Duration waitTime);

    /**
     * Use {@link #tryAcquire(int, Duration)} instead
     *
     * @param permits amount of permits
     * @param waitTime the maximum time to wait
     * @param unit the time unit
     * @return true if permits were acquired and false
     *         otherwise
     */
    @Deprecated
    Single tryAcquire(int permits, long waitTime, TimeUnit unit);

    /**
     * Tries to acquire defined amount of currently available permits.
     * Waits up to defined waitTime if necessary until all permits became available.
     *
     * @param permits amount of permits
     * @param waitTime the maximum time to wait
     * @return true if permits were acquired and false
     *         otherwise
     */
    Single tryAcquire(int permits, Duration waitTime);

    /**
     * Increases or decreases the number of available permits by defined value.
     *
     * @param permits amount of permits to add/remove
     */
    Completable addPermits(int permits);

    /**
     * Returns amount of available permits.
     *
     * @return number of permits
     */
    Single availablePermits();

    /**
     * Acquires and returns all permits that are immediately available.
     *
     * @return number of permits
     */
    Single drainPermits();

}