org.redisson.RedissonBlockingQueue.java Source code

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Here is the source code for org.redisson.RedissonBlockingQueue.java

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/**
 * Copyright 2014 Nikita Koksharov, Nickolay Borbit
 *
 * 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;

import java.util.ArrayList;
import java.util.Collection;
import java.util.Collections;
import java.util.List;
import java.util.concurrent.TimeUnit;

import org.redisson.client.codec.Codec;
import org.redisson.client.protocol.RedisCommand;
import org.redisson.client.protocol.RedisCommands;
import org.redisson.command.CommandAsyncExecutor;
import org.redisson.connection.decoder.ListDrainToDecoder;
import org.redisson.core.RBlockingQueue;

import io.netty.util.concurrent.Future;

/**
 * <p>Distributed and concurrent implementation of {@link java.util.concurrent.BlockingQueue}.
 *
 * <p>Queue size limited by Redis server memory amount. This is why {@link #remainingCapacity()} always
 * returns <code>Integer.MAX_VALUE</code>
 *
 * @author pdeschen@gmail.com
 * @author Nikita Koksharov
 */
public class RedissonBlockingQueue<V> extends RedissonQueue<V> implements RBlockingQueue<V> {

    protected RedissonBlockingQueue(CommandAsyncExecutor commandExecutor, String name) {
        super(commandExecutor, name);
    }

    protected RedissonBlockingQueue(Codec codec, CommandAsyncExecutor commandExecutor, String name) {
        super(codec, commandExecutor, name);
    }

    @Override
    public Future<Boolean> putAsync(V e) {
        return offerAsync(e);
    }

    /*
     * (non-Javadoc)
     * @see java.util.concurrent.BlockingQueue#put(java.lang.Object)
     */
    @Override
    public void put(V e) throws InterruptedException {
        offer(e);
    }

    @Override
    public boolean offer(V e, long timeout, TimeUnit unit) throws InterruptedException {
        return offer(e);
    }

    @Override
    public Future<V> takeAsync() {
        return commandExecutor.writeAsync(getName(), codec, RedisCommands.BLPOP_VALUE, getName(), 0);
    }

    /*
     * (non-Javadoc)
     * @see java.util.concurrent.BlockingQueue#take()
     */
    @Override
    public V take() throws InterruptedException {
        Future<V> res = takeAsync();
        return res.await().getNow();
    }

    @Override
    public Future<V> pollAsync(long timeout, TimeUnit unit) {
        return commandExecutor.writeAsync(getName(), codec, RedisCommands.BLPOP_VALUE, getName(),
                unit.toSeconds(timeout));
    }

    /*
     * (non-Javadoc)
     * @see java.util.concurrent.BlockingQueue#poll(long, java.util.concurrent.TimeUnit)
     */
    @Override
    public V poll(long timeout, TimeUnit unit) throws InterruptedException {
        Future<V> res = pollAsync(timeout, unit);
        return res.await().getNow();
    }

    /*
     * (non-Javadoc)
     * @see org.redisson.core.RBlockingQueue#pollFromAny(long, java.util.concurrent.TimeUnit, java.lang.String[])
     */
    @Override
    public V pollFromAny(long timeout, TimeUnit unit, String... queueNames) throws InterruptedException {
        Future<V> res = pollFromAnyAsync(timeout, unit, queueNames);
        return res.await().getNow();
    }

    /*
     * (non-Javadoc)
     * @see org.redisson.core.RBlockingQueueAsync#pollFromAnyAsync(long, java.util.concurrent.TimeUnit, java.lang.String[])
     */
    @Override
    public Future<V> pollFromAnyAsync(long timeout, TimeUnit unit, String... queueNames) {
        List<Object> params = new ArrayList<Object>(queueNames.length + 1);
        params.add(getName());
        for (Object name : queueNames) {
            params.add(name);
        }
        params.add(unit.toSeconds(timeout));
        return commandExecutor.writeAsync(getName(), codec, RedisCommands.BLPOP_VALUE, params.toArray());
    }

    @Override
    public Future<V> pollLastAndOfferFirstToAsync(String queueName, long timeout, TimeUnit unit) {
        return commandExecutor.writeAsync(getName(), codec, RedisCommands.BRPOPLPUSH, getName(), queueName,
                unit.toSeconds(timeout));
    }

    @Override
    public V pollLastAndOfferFirstTo(String queueName, long timeout, TimeUnit unit) throws InterruptedException {
        Future<V> res = pollLastAndOfferFirstToAsync(queueName, timeout, unit);
        return res.await().getNow();
    }

    @Override
    public int remainingCapacity() {
        return Integer.MAX_VALUE;
    }

    @Override
    public int drainTo(Collection<? super V> c) {
        return get(drainToAsync(c));
    }

    @Override
    public Future<Integer> drainToAsync(Collection<? super V> c) {
        if (c == null) {
            throw new NullPointerException();
        }

        return commandExecutor
                .evalWriteAsync(getName(), codec, new RedisCommand<Object>("EVAL", new ListDrainToDecoder(c)),
                        "local vals = redis.call('lrange', KEYS[1], 0, -1); "
                                + "redis.call('ltrim', KEYS[1], -1, 0); " + "return vals",
                        Collections.<Object>singletonList(getName()));
    }

    @Override
    public int drainTo(Collection<? super V> c, int maxElements) {
        if (maxElements <= 0) {
            return 0;
        }

        return get(drainToAsync(c, maxElements));
    }

    @Override
    public Future<Integer> drainToAsync(Collection<? super V> c, int maxElements) {
        if (c == null) {
            throw new NullPointerException();
        }
        return commandExecutor.evalWriteAsync(getName(), codec,
                new RedisCommand<Object>("EVAL", new ListDrainToDecoder(c)),
                "local elemNum = math.min(ARGV[1], redis.call('llen', KEYS[1])) - 1;"
                        + "local vals = redis.call('lrange', KEYS[1], 0, elemNum); "
                        + "redis.call('ltrim', KEYS[1], elemNum + 1, -1); " + "return vals",
                Collections.<Object>singletonList(getName()), maxElements);
    }
}