Java tutorial
/** * Copyright 2016 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; import java.util.Arrays; import java.util.Collections; import java.util.UUID; import java.util.concurrent.TimeUnit; import java.util.concurrent.atomic.AtomicBoolean; import java.util.concurrent.atomic.AtomicInteger; import java.util.concurrent.atomic.AtomicReference; import org.redisson.api.RBlockingFairQueue; import org.redisson.api.RFuture; import org.redisson.client.codec.Codec; import org.redisson.client.codec.LongCodec; import org.redisson.client.codec.StringCodec; import org.redisson.client.protocol.RedisCommands; import org.redisson.command.CommandExecutor; import org.redisson.misc.RPromise; import org.redisson.pubsub.SemaphorePubSub; import io.netty.util.Timeout; import io.netty.util.TimerTask; import io.netty.util.concurrent.Future; import io.netty.util.concurrent.FutureListener; /** * * @author Nikita Koksharov * */ public class RedissonBlockingFairQueue<V> extends RedissonBlockingQueue<V> implements RBlockingFairQueue<V> { public static final long TIMEOUT_SECONDS = 30; private final UUID id; private final AtomicInteger instances = new AtomicInteger(); private final SemaphorePubSub semaphorePubSub; protected RedissonBlockingFairQueue(CommandExecutor commandExecutor, String name, SemaphorePubSub semaphorePubSub, UUID id) { super(commandExecutor, name); this.semaphorePubSub = semaphorePubSub; this.id = id; instances.incrementAndGet(); } protected RedissonBlockingFairQueue(Codec codec, CommandExecutor commandExecutor, String name, SemaphorePubSub semaphorePubSub, UUID id) { super(codec, commandExecutor, name); this.semaphorePubSub = semaphorePubSub; this.id = id; instances.incrementAndGet(); } private String getIdsListName() { return suffixName(getName(), "list"); } private String getTimeoutName() { return suffixName(getName(), "timeout"); } private String getChannelName() { return suffixName(getName(), getCurrentId() + ":channel"); } private RedissonLockEntry getEntry() { return semaphorePubSub.getEntry(getName()); } private RFuture<RedissonLockEntry> subscribe() { return semaphorePubSub.subscribe(getName(), getChannelName(), commandExecutor.getConnectionManager()); } private void unsubscribe(RFuture<RedissonLockEntry> future) { semaphorePubSub.unsubscribe(future.getNow(), getName(), getChannelName(), commandExecutor.getConnectionManager()); } @Override public RFuture<Boolean> deleteAsync() { return commandExecutor.writeAsync(getName(), RedisCommands.DEL_OBJECTS, getName(), getIdsListName(), getTimeoutName()); } private Long tryAcquire() { return get(tryAcquireAsync()); } private RFuture<Long> tryAcquireAsync() { long timeout = System.currentTimeMillis() + TIMEOUT_SECONDS * 1000; return commandExecutor.evalWriteAsync(getName(), LongCodec.INSTANCE, RedisCommands.EVAL_LONG, "local timeout = redis.call('get', KEYS[3]);" + "if timeout ~= false and tonumber(timeout) <= tonumber(ARGV[3]) then " + "redis.call('lpop', KEYS[2]); " + "local nextValue = redis.call('lindex', KEYS[2], 0); " + "if nextValue ~= false and nextValue ~= ARGV[1] then " + "redis.call('set', KEYS[3], ARGV[2]);" + "redis.call('publish', '{' .. KEYS[1] .. '}:' .. nextValue .. ':channel', 1);" + "end; " + "end; " + "local items = redis.call('lrange', KEYS[2], 0, -1) " + "local found = false; " + "for i=1,#items do " + "if items[i] == ARGV[1] then " + "found = true; " + "break;" + "end; " + "end; " + "if found == false then " + "redis.call('lpush', KEYS[2], ARGV[1]); " + "end; " + "local value = redis.call('lindex', KEYS[2], 0); " + "if value == ARGV[1] then " + "redis.call('set', KEYS[3], ARGV[2]);" + "local size = redis.call('llen', KEYS[2]); " + "if size > 1 then " + "redis.call('lpop', KEYS[2]);" + "redis.call('rpush', KEYS[2], value);" + "local nextValue = redis.call('lindex', KEYS[2], 0); " + "redis.call('publish', '{' .. KEYS[1] .. '}:' .. nextValue .. ':channel', 1);" + "end; " + "return nil;" + "end;" + "return tonumber(timeout) - tonumber(ARGV[3]);", Arrays.<Object>asList(getName(), getIdsListName(), getTimeoutName()), getCurrentId(), timeout, System.currentTimeMillis()); } private String getCurrentId() { return id.toString(); } @Override public V take() throws InterruptedException { Long currentTimeout = tryAcquire(); if (currentTimeout == null) { return super.take(); } RFuture<RedissonLockEntry> future = subscribe(); commandExecutor.syncSubscription(future); try { while (true) { currentTimeout = tryAcquire(); if (currentTimeout == null) { return super.take(); } getEntry().getLatch().tryAcquire(currentTimeout, TimeUnit.MILLISECONDS); } } finally { unsubscribe(future); } } @Override public void destroy() { if (instances.decrementAndGet() == 0) { get(commandExecutor.evalWriteAsync(getName(), StringCodec.INSTANCE, RedisCommands.EVAL_VOID_WITH_VALUES, "for i = 1, #ARGV, 1 do " + "redis.call('lrem', KEYS[1], 0, ARGV[i]);" + "end; ", Collections.<Object>singletonList(getIdsListName()), getCurrentId())); } } @Override public RFuture<V> takeAsync() { final RPromise<V> promise = newPromise(); RFuture<Long> tryAcquireFuture = tryAcquireAsync(); tryAcquireFuture.addListener(new FutureListener<Long>() { @Override public void operationComplete(Future<Long> future) throws Exception { if (!future.isSuccess()) { promise.tryFailure(future.cause()); return; } final Long currentTimeout = future.getNow(); if (currentTimeout == null) { final RFuture<V> pollFuture = RedissonBlockingFairQueue.super.takeAsync(); pollFuture.addListener(new FutureListener<V>() { @Override public void operationComplete(Future<V> future) throws Exception { if (!future.isSuccess()) { promise.tryFailure(future.cause()); return; } promise.trySuccess(future.getNow()); } }); } else { final RFuture<RedissonLockEntry> subscribeFuture = subscribe(); final AtomicReference<Timeout> futureRef = new AtomicReference<Timeout>(); subscribeFuture.addListener(new FutureListener<RedissonLockEntry>() { @Override public void operationComplete(Future<RedissonLockEntry> future) throws Exception { if (!future.isSuccess()) { promise.tryFailure(future.cause()); return; } if (futureRef.get() != null) { futureRef.get().cancel(); } tryTakeAsync(subscribeFuture, promise); } }); } } }); return promise; } @Override public V poll() { Long currentTimeout = tryAcquire(); if (currentTimeout == null) { return super.poll(); } return null; } @Override public RFuture<V> pollAsync() { final RPromise<V> promise = newPromise(); RFuture<Long> tryAcquireFuture = tryAcquireAsync(); tryAcquireFuture.addListener(new FutureListener<Long>() { @Override public void operationComplete(Future<Long> future) throws Exception { if (!future.isSuccess()) { promise.tryFailure(future.cause()); return; } final Long currentTimeout = future.getNow(); if (currentTimeout == null) { final RFuture<V> pollFuture = RedissonBlockingFairQueue.super.pollAsync(); pollFuture.addListener(new FutureListener<V>() { @Override public void operationComplete(Future<V> future) throws Exception { if (!future.isSuccess()) { promise.tryFailure(future.cause()); return; } promise.trySuccess(future.getNow()); } }); } else { promise.trySuccess(null); } } }); return promise; } @Override public V poll(long timeout, TimeUnit unit) throws InterruptedException { long startTime = System.currentTimeMillis(); Long currentTimeout = tryAcquire(); if (currentTimeout == null) { long spentTime = System.currentTimeMillis() - startTime; long remainTime = unit.toMillis(timeout) - spentTime; if (remainTime > 0) { return super.poll(remainTime, TimeUnit.MILLISECONDS); } return null; } RFuture<RedissonLockEntry> future = subscribe(); long spentTime = System.currentTimeMillis() - startTime; long remainTime = unit.toMillis(timeout) - spentTime; if (!future.awaitUninterruptibly(remainTime, TimeUnit.MILLISECONDS)) { return null; } try { while (true) { currentTimeout = tryAcquire(); if (currentTimeout == null) { spentTime = System.currentTimeMillis() - startTime; remainTime = unit.toMillis(timeout) - spentTime; if (remainTime > 0) { return super.poll(remainTime, TimeUnit.MILLISECONDS); } return null; } spentTime = System.currentTimeMillis() - startTime; remainTime = unit.toMillis(timeout) - spentTime; remainTime = Math.min(remainTime, currentTimeout); if (remainTime <= 0 || !getEntry().getLatch().tryAcquire(remainTime, TimeUnit.MILLISECONDS)) { return null; } } } finally { unsubscribe(future); } } @Override public RFuture<V> pollAsync(final long timeout, final TimeUnit unit) { final long startTime = System.currentTimeMillis(); final RPromise<V> promise = newPromise(); RFuture<Long> tryAcquireFuture = tryAcquireAsync(); tryAcquireFuture.addListener(new FutureListener<Long>() { @Override public void operationComplete(Future<Long> future) throws Exception { if (!future.isSuccess()) { promise.tryFailure(future.cause()); return; } Long currentTimeout = future.getNow(); if (currentTimeout == null) { long spentTime = System.currentTimeMillis() - startTime; long remainTime = unit.toMillis(timeout) - spentTime; if (remainTime > 0) { final RFuture<V> pollFuture = RedissonBlockingFairQueue.super.pollAsync(remainTime, TimeUnit.MILLISECONDS); pollFuture.addListener(new FutureListener<V>() { @Override public void operationComplete(Future<V> future) throws Exception { if (!future.isSuccess()) { promise.tryFailure(future.cause()); return; } promise.trySuccess(future.getNow()); } }); } else { promise.trySuccess(null); } } else { long spentTime = System.currentTimeMillis() - startTime; long remainTime = unit.toMillis(timeout) - spentTime; remainTime = Math.min(remainTime, currentTimeout); if (remainTime <= 0) { promise.trySuccess(null); return; } final RFuture<RedissonLockEntry> subscribeFuture = subscribe(); final AtomicReference<Timeout> futureRef = new AtomicReference<Timeout>(); subscribeFuture.addListener(new FutureListener<RedissonLockEntry>() { @Override public void operationComplete(Future<RedissonLockEntry> future) throws Exception { if (!future.isSuccess()) { promise.tryFailure(future.cause()); return; } if (futureRef.get() != null) { futureRef.get().cancel(); } tryPollAsync(startTime, timeout, unit, subscribeFuture, promise); } }); if (!subscribeFuture.isDone()) { Timeout scheduledFuture = commandExecutor.getConnectionManager() .newTimeout(new TimerTask() { @Override public void run(Timeout timeout) throws Exception { if (!subscribeFuture.isDone()) { subscribeFuture.cancel(false); promise.trySuccess(null); } } }, remainTime, TimeUnit.MILLISECONDS); futureRef.set(scheduledFuture); } } } }); return promise; } private void tryTakeAsync(final RFuture<RedissonLockEntry> subscribeFuture, final RPromise<V> promise) { if (promise.isDone()) { unsubscribe(subscribeFuture); return; } RFuture<Long> tryAcquireFuture = tryAcquireAsync(); tryAcquireFuture.addListener(new FutureListener<Long>() { @Override public void operationComplete(Future<Long> future) throws Exception { if (!future.isSuccess()) { unsubscribe(subscribeFuture); promise.tryFailure(future.cause()); return; } Long currentTimeout = future.getNow(); if (currentTimeout == null) { final RFuture<V> pollFuture = RedissonBlockingFairQueue.super.takeAsync(); pollFuture.addListener(new FutureListener<V>() { @Override public void operationComplete(Future<V> future) throws Exception { unsubscribe(subscribeFuture); if (!future.isSuccess()) { promise.tryFailure(future.cause()); return; } promise.trySuccess(future.getNow()); } }); } else { final RedissonLockEntry entry = getEntry(); synchronized (entry) { if (entry.getLatch().tryAcquire()) { tryTakeAsync(subscribeFuture, promise); } else { final AtomicBoolean executed = new AtomicBoolean(); final AtomicReference<Timeout> futureRef = new AtomicReference<Timeout>(); final Runnable listener = new Runnable() { @Override public void run() { executed.set(true); if (futureRef.get() != null) { futureRef.get().cancel(); } tryTakeAsync(subscribeFuture, promise); } }; entry.addListener(listener); if (!executed.get()) { Timeout scheduledFuture = commandExecutor.getConnectionManager() .newTimeout(new TimerTask() { @Override public void run(Timeout t) throws Exception { synchronized (entry) { if (entry.removeListener(listener)) { tryTakeAsync(subscribeFuture, promise); } } } }, currentTimeout, TimeUnit.MILLISECONDS); futureRef.set(scheduledFuture); } } } } }; }); } private void tryPollAsync(final long startTime, final long timeout, final TimeUnit unit, final RFuture<RedissonLockEntry> subscribeFuture, final RPromise<V> promise) { if (promise.isDone()) { unsubscribe(subscribeFuture); return; } long spentTime = System.currentTimeMillis() - startTime; long remainTime = unit.toMillis(timeout) - spentTime; if (remainTime <= 0) { unsubscribe(subscribeFuture); promise.trySuccess(null); return; } RFuture<Long> tryAcquireFuture = tryAcquireAsync(); tryAcquireFuture.addListener(new FutureListener<Long>() { @Override public void operationComplete(Future<Long> future) throws Exception { if (!future.isSuccess()) { unsubscribe(subscribeFuture); promise.tryFailure(future.cause()); return; } Long currentTimeout = future.getNow(); if (currentTimeout == null) { long spentTime = System.currentTimeMillis() - startTime; long remainTime = unit.toMillis(timeout) - spentTime; if (remainTime > 0) { final RFuture<V> pollFuture = RedissonBlockingFairQueue.super.pollAsync(remainTime, TimeUnit.MILLISECONDS); pollFuture.addListener(new FutureListener<V>() { @Override public void operationComplete(Future<V> future) throws Exception { unsubscribe(subscribeFuture); if (!future.isSuccess()) { promise.tryFailure(future.cause()); return; } promise.trySuccess(future.getNow()); } }); } else { unsubscribe(subscribeFuture); promise.trySuccess(null); } } else { final RedissonLockEntry entry = getEntry(); synchronized (entry) { if (entry.getLatch().tryAcquire()) { tryPollAsync(startTime, timeout, unit, subscribeFuture, promise); } else { final AtomicBoolean executed = new AtomicBoolean(); final AtomicReference<Timeout> futureRef = new AtomicReference<Timeout>(); final Runnable listener = new Runnable() { @Override public void run() { executed.set(true); if (futureRef.get() != null) { futureRef.get().cancel(); } tryPollAsync(startTime, timeout, unit, subscribeFuture, promise); } }; entry.addListener(listener); if (!executed.get()) { long spentTime = System.currentTimeMillis() - startTime; long remainTime = unit.toMillis(timeout) - spentTime; Timeout scheduledFuture = commandExecutor.getConnectionManager() .newTimeout(new TimerTask() { @Override public void run(Timeout t) throws Exception { synchronized (entry) { if (entry.removeListener(listener)) { tryPollAsync(startTime, timeout, unit, subscribeFuture, promise); } } } }, remainTime, TimeUnit.MILLISECONDS); futureRef.set(scheduledFuture); } } } } }; }); } @Override public V pollLastAndOfferFirstTo(String queueName, long timeout, TimeUnit unit) throws InterruptedException { long startTime = System.currentTimeMillis(); Long currentTimeout = tryAcquire(); if (currentTimeout == null) { long spentTime = System.currentTimeMillis() - startTime; long remainTime = unit.toMillis(timeout) - spentTime; if (remainTime > 0) { return super.pollLastAndOfferFirstTo(queueName, remainTime, TimeUnit.MILLISECONDS); } return null; } RFuture<RedissonLockEntry> future = subscribe(); long spentTime = System.currentTimeMillis() - startTime; long remainTime = unit.toMillis(timeout) - spentTime; if (!future.awaitUninterruptibly(remainTime, TimeUnit.MILLISECONDS)) { return null; } try { while (true) { currentTimeout = tryAcquire(); if (currentTimeout == null) { spentTime = System.currentTimeMillis() - startTime; remainTime = unit.toMillis(timeout) - spentTime; if (remainTime > 0) { return super.pollLastAndOfferFirstTo(queueName, remainTime, TimeUnit.MILLISECONDS); } return null; } spentTime = System.currentTimeMillis() - startTime; remainTime = unit.toMillis(timeout) - spentTime; remainTime = Math.min(remainTime, currentTimeout); if (remainTime <= 0 || !getEntry().getLatch().tryAcquire(remainTime, TimeUnit.MILLISECONDS)) { return null; } } } finally { unsubscribe(future); } } @Override public RFuture<V> pollLastAndOfferFirstToAsync(final String queueName, final long timeout, final TimeUnit unit) { final long startTime = System.currentTimeMillis(); final RPromise<V> promise = newPromise(); RFuture<Long> tryAcquireFuture = tryAcquireAsync(); tryAcquireFuture.addListener(new FutureListener<Long>() { @Override public void operationComplete(Future<Long> future) throws Exception { if (!future.isSuccess()) { promise.tryFailure(future.cause()); return; } Long currentTimeout = future.getNow(); if (currentTimeout == null) { long spentTime = System.currentTimeMillis() - startTime; long remainTime = unit.toMillis(timeout) - spentTime; if (remainTime > 0) { final RFuture<V> pollFuture = RedissonBlockingFairQueue.super.pollLastAndOfferFirstToAsync( queueName, remainTime, TimeUnit.MILLISECONDS); pollFuture.addListener(new FutureListener<V>() { @Override public void operationComplete(Future<V> future) throws Exception { if (!future.isSuccess()) { promise.tryFailure(future.cause()); return; } promise.trySuccess(future.getNow()); } }); } else { promise.trySuccess(null); } } else { long spentTime = System.currentTimeMillis() - startTime; long remainTime = unit.toMillis(timeout) - spentTime; remainTime = Math.min(remainTime, currentTimeout); if (remainTime <= 0) { promise.trySuccess(null); return; } final RFuture<RedissonLockEntry> subscribeFuture = subscribe(); final AtomicReference<Timeout> futureRef = new AtomicReference<Timeout>(); subscribeFuture.addListener(new FutureListener<RedissonLockEntry>() { @Override public void operationComplete(Future<RedissonLockEntry> future) throws Exception { if (!future.isSuccess()) { promise.tryFailure(future.cause()); return; } if (futureRef.get() != null) { futureRef.get().cancel(); } tryPollLastAndOfferFirstToAsync(startTime, timeout, unit, subscribeFuture, promise, queueName); } }); if (!subscribeFuture.isDone()) { Timeout scheduledFuture = commandExecutor.getConnectionManager() .newTimeout(new TimerTask() { @Override public void run(Timeout timeout) throws Exception { if (!subscribeFuture.isDone()) { subscribeFuture.cancel(false); promise.trySuccess(null); } } }, remainTime, TimeUnit.MILLISECONDS); futureRef.set(scheduledFuture); } } } }); return promise; } private void tryPollLastAndOfferFirstToAsync(final long startTime, final long timeout, final TimeUnit unit, final RFuture<RedissonLockEntry> subscribeFuture, final RPromise<V> promise, final String queueName) { if (promise.isDone()) { unsubscribe(subscribeFuture); return; } long spentTime = System.currentTimeMillis() - startTime; long remainTime = unit.toMillis(timeout) - spentTime; if (remainTime <= 0) { unsubscribe(subscribeFuture); promise.trySuccess(null); return; } RFuture<Long> tryAcquireFuture = tryAcquireAsync(); tryAcquireFuture.addListener(new FutureListener<Long>() { @Override public void operationComplete(Future<Long> future) throws Exception { if (!future.isSuccess()) { unsubscribe(subscribeFuture); promise.tryFailure(future.cause()); return; } Long currentTimeout = future.getNow(); if (currentTimeout == null) { long spentTime = System.currentTimeMillis() - startTime; long remainTime = unit.toMillis(timeout) - spentTime; if (remainTime > 0) { final RFuture<V> pollFuture = RedissonBlockingFairQueue.super.pollLastAndOfferFirstToAsync( queueName, remainTime, TimeUnit.MILLISECONDS); pollFuture.addListener(new FutureListener<V>() { @Override public void operationComplete(Future<V> future) throws Exception { unsubscribe(subscribeFuture); if (!future.isSuccess()) { promise.tryFailure(future.cause()); return; } promise.trySuccess(future.getNow()); } }); } else { unsubscribe(subscribeFuture); promise.trySuccess(null); } } else { final RedissonLockEntry entry = getEntry(); synchronized (entry) { if (entry.getLatch().tryAcquire()) { tryPollAsync(startTime, timeout, unit, subscribeFuture, promise); } else { final AtomicBoolean executed = new AtomicBoolean(); final AtomicReference<Timeout> futureRef = new AtomicReference<Timeout>(); final Runnable listener = new Runnable() { @Override public void run() { executed.set(true); if (futureRef.get() != null) { futureRef.get().cancel(); } tryPollLastAndOfferFirstToAsync(startTime, timeout, unit, subscribeFuture, promise, queueName); } }; entry.addListener(listener); if (!executed.get()) { long spentTime = System.currentTimeMillis() - startTime; long remainTime = unit.toMillis(timeout) - spentTime; Timeout scheduledFuture = commandExecutor.getConnectionManager() .newTimeout(new TimerTask() { @Override public void run(Timeout t) throws Exception { synchronized (entry) { if (entry.removeListener(listener)) { tryPollLastAndOfferFirstToAsync(startTime, timeout, unit, subscribeFuture, promise, queueName); } } } }, remainTime, TimeUnit.MILLISECONDS); futureRef.set(scheduledFuture); } } } } }; }); } }