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RedisMessageListenerContainer.java
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RedisMessageListenerContainer.java
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/*
* Copyright 2011-2020 the original author or authors.
*
* 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
*
* https://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.springframework.data.redis.listener;
import java.util.ArrayList;
import java.util.Collection;
import java.util.Collections;
import java.util.List;
import java.util.Map;
import java.util.Set;
import java.util.concurrent.ConcurrentHashMap;
import java.util.concurrent.CopyOnWriteArraySet;
import java.util.concurrent.Executor;
import java.util.concurrent.TimeUnit;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.springframework.beans.factory.BeanNameAware;
import org.springframework.beans.factory.DisposableBean;
import org.springframework.beans.factory.InitializingBean;
import org.springframework.context.SmartLifecycle;
import org.springframework.core.task.SimpleAsyncTaskExecutor;
import org.springframework.core.task.TaskExecutor;
import org.springframework.data.redis.RedisConnectionFailureException;
import org.springframework.data.redis.connection.ConnectionUtils;
import org.springframework.data.redis.connection.Message;
import org.springframework.data.redis.connection.MessageListener;
import org.springframework.data.redis.connection.RedisConnection;
import org.springframework.data.redis.connection.RedisConnectionFactory;
import org.springframework.data.redis.connection.Subscription;
import org.springframework.data.redis.connection.util.ByteArrayWrapper;
import org.springframework.data.redis.serializer.RedisSerializer;
import org.springframework.data.redis.serializer.StringRedisSerializer;
import org.springframework.lang.Nullable;
import org.springframework.scheduling.SchedulingAwareRunnable;
import org.springframework.util.Assert;
import org.springframework.util.ClassUtils;
import org.springframework.util.CollectionUtils;
import org.springframework.util.ErrorHandler;
/**
* Container providing asynchronous behaviour for Redis message listeners. Handles the low level details of listening,
* converting and message dispatching.
* <p>
* As oppose to the low level Redis (one connection per subscription), the container uses only one connection that is
* 'multiplexed' for all registered listeners, the message dispatch being done through the task executor.
* <p>
* Note the container uses the connection in a lazy fashion (the connection is used only if at least one listener is
* configured).
* <p>
* Adding and removing listeners at the same time has undefined results. It is strongly recommended to synchronize/order
* these methods accordingly.
*
* @author Costin Leau
* @author Jennifer Hickey
* @author Way Joke
* @author Thomas Darimont
* @author Mark Paluch
*/
public class RedisMessageListenerContainer implements InitializingBean, DisposableBean, BeanNameAware, SmartLifecycle {
/** Logger available to subclasses */
protected final Log logger = LogFactory.getLog(getClass());
/**
* Default thread name prefix: "RedisListeningContainer-".
*/
public static final String DEFAULT_THREAD_NAME_PREFIX = ClassUtils.getShortName(RedisMessageListenerContainer.class)
+ "-";
/**
* The default recovery interval: 5000 ms = 5 seconds.
*/
public static final long DEFAULT_RECOVERY_INTERVAL = 5000;
/**
* The default subscription wait time: 2000 ms = 2 seconds.
*/
public static final long DEFAULT_SUBSCRIPTION_REGISTRATION_WAIT_TIME = 2000L;
private long initWait = TimeUnit.SECONDS.toMillis(5);
private @Nullable Executor subscriptionExecutor;
private @Nullable Executor taskExecutor;
private @Nullable RedisConnectionFactory connectionFactory;
private @Nullable String beanName;
private @Nullable ErrorHandler errorHandler;
private final Object monitor = new Object();
// whether the container is running (or not)
private volatile boolean running = false;
// whether the container has been initialized
private volatile boolean initialized = false;
// whether the container uses a connection or not
// (as the container might be running but w/o listeners, it won't use any resources)
private volatile boolean listening = false;
private volatile boolean manageExecutor = false;
// lookup maps
// to avoid creation of hashes for each message, the maps use raw byte arrays (wrapped to respect the equals/hashcode
// contract)
// lookup map between patterns and listeners
private final Map<ByteArrayWrapper, Collection<MessageListener>> patternMapping = new ConcurrentHashMap<>();
// lookup map between channels and listeners
private final Map<ByteArrayWrapper, Collection<MessageListener>> channelMapping = new ConcurrentHashMap<>();
// lookup map between listeners and channels
private final Map<MessageListener, Set<Topic>> listenerTopics = new ConcurrentHashMap<>();
private final SubscriptionTask subscriptionTask = new SubscriptionTask();
private volatile RedisSerializer<String> serializer = RedisSerializer.string();
private long recoveryInterval = DEFAULT_RECOVERY_INTERVAL;
private long maxSubscriptionRegistrationWaitingTime = DEFAULT_SUBSCRIPTION_REGISTRATION_WAIT_TIME;
public void afterPropertiesSet() {
if (taskExecutor == null) {
manageExecutor = true;
taskExecutor = createDefaultTaskExecutor();
}
if (subscriptionExecutor == null) {
subscriptionExecutor = taskExecutor;
}
initialized = true;
}
/**
* Creates a default TaskExecutor. Called if no explicit TaskExecutor has been specified.
* <p>
* The default implementation builds a {@link org.springframework.core.task.SimpleAsyncTaskExecutor} with the
* specified bean name (or the class name, if no bean name specified) as thread name prefix.
*
* @see org.springframework.core.task.SimpleAsyncTaskExecutor#SimpleAsyncTaskExecutor(String)
*/
protected TaskExecutor createDefaultTaskExecutor() {
String threadNamePrefix = (beanName != null ? beanName + "-" : DEFAULT_THREAD_NAME_PREFIX);
return new SimpleAsyncTaskExecutor(threadNamePrefix);
}
public void destroy() throws Exception {
initialized = false;
stop();
if (manageExecutor) {
if (taskExecutor instanceof DisposableBean) {
((DisposableBean) taskExecutor).destroy();
if (logger.isDebugEnabled()) {
logger.debug("Stopped internally-managed task executor");
}
}
}
}
public boolean isAutoStartup() {
return true;
}
public void stop(Runnable callback) {
stop();
callback.run();
}
public int getPhase() {
// start the latest
return Integer.MAX_VALUE;
}
public boolean isRunning() {
return running;
}
public void start() {
if (!running) {
running = true;
// wait for the subscription to start before returning
// technically speaking we can only be notified right before the subscription starts
synchronized (monitor) {
lazyListen();
if (listening) {
try {
// wait up to 5 seconds for Subscription thread
monitor.wait(initWait);
} catch (InterruptedException e) {
// stop waiting
Thread.currentThread().interrupt();
running = false;
return;
}
}
}
if (logger.isDebugEnabled()) {
logger.debug("Started RedisMessageListenerContainer");
}
}
}
public void stop() {
if (isRunning()) {
running = false;
subscriptionTask.cancel();
}
if (logger.isDebugEnabled()) {
logger.debug("Stopped RedisMessageListenerContainer");
}
}
/**
* Process a message received from the provider.
*
* @param message
* @param pattern
*/
protected void processMessage(MessageListener listener, Message message, byte[] pattern) {
executeListener(listener, message, pattern);
}
/**
* Execute the specified listener.
*
* @see #handleListenerException
*/
protected void executeListener(MessageListener listener, Message message, byte[] pattern) {
try {
listener.onMessage(message, pattern);
} catch (Throwable ex) {
handleListenerException(ex);
}
}
/**
* Return whether this container is currently active, that is, whether it has been set up but not shut down yet.
*/
public final boolean isActive() {
return initialized;
}
/**
* Handle the given exception that arose during listener execution.
* <p>
* The default implementation logs the exception at error level. This can be overridden in subclasses.
*
* @param ex the exception to handle
*/
protected void handleListenerException(Throwable ex) {
if (isActive()) {
// Regular case: failed while active.
// Invoke ErrorHandler if available.
invokeErrorHandler(ex);
} else {
// Rare case: listener thread failed after container shutdown.
// Log at debug level, to avoid spamming the shutdown logger.
logger.debug("Listener exception after container shutdown", ex);
}
}
/**
* Invoke the registered ErrorHandler, if any. Log at error level otherwise.
*
* @param ex the uncaught error that arose during message processing.
* @see #setErrorHandler
*/
protected void invokeErrorHandler(Throwable ex) {
if (this.errorHandler != null) {
this.errorHandler.handleError(ex);
} else if (logger.isWarnEnabled()) {
logger.warn("Execution of message listener failed, and no ErrorHandler has been set.", ex);
}
}
/**
* Returns the connectionFactory.
*
* @return Returns the connectionFactory
*/
@Nullable
public RedisConnectionFactory getConnectionFactory() {
return connectionFactory;
}
/**
* @param connectionFactory The connectionFactory to set.
*/
public void setConnectionFactory(RedisConnectionFactory connectionFactory) {
Assert.notNull(connectionFactory, "ConnectionFactory must not be null!");
this.connectionFactory = connectionFactory;
}
public void setBeanName(String name) {
this.beanName = name;
}
/**
* Sets the task executor used for running the message listeners when messages are received. If no task executor is
* set, an instance of {@link SimpleAsyncTaskExecutor} will be used by default. The task executor can be adjusted
* depending on the work done by the listeners and the number of messages coming in.
*
* @param taskExecutor The taskExecutor to set.
*/
public void setTaskExecutor(Executor taskExecutor) {
this.taskExecutor = taskExecutor;
}
/**
* Sets the task execution used for subscribing to Redis channels. By default, if no executor is set, the
* {@link #setTaskExecutor(Executor)} will be used. In some cases, this might be undersired as the listening to the
* connection is a long running task.
* <p>
* Note: This implementation uses at most one long running thread (depending on whether there are any listeners
* registered or not) and up to two threads during the initial registration.
*
* @param subscriptionExecutor The subscriptionExecutor to set.
*/
public void setSubscriptionExecutor(Executor subscriptionExecutor) {
this.subscriptionExecutor = subscriptionExecutor;
}
/**
* Sets the serializer for converting the {@link Topic}s into low-level channels and patterns. By default,
* {@link StringRedisSerializer} is used.
*
* @param serializer The serializer to set.
*/
public void setTopicSerializer(RedisSerializer<String> serializer) {
this.serializer = serializer;
}
/**
* Set an ErrorHandler to be invoked in case of any uncaught exceptions thrown while processing a Message. By default
* there will be <b>no</b> ErrorHandler so that error-level logging is the only result.
*/
public void setErrorHandler(ErrorHandler errorHandler) {
this.errorHandler = errorHandler;
}
/**
* Attaches the given listeners (and their topics) to the container.
* <p>
* Note: it's possible to call this method while the container is running forcing a reinitialization of the container.
* Note however that this might cause some messages to be lost (while the container reinitializes) - hence calling
* this method at runtime is considered advanced usage.
*
* @param listeners map of message listeners and their associated topics
*/
public void setMessageListeners(Map<? extends MessageListener, Collection<? extends Topic>> listeners) {
initMapping(listeners);
}
/**
* Adds a message listener to the (potentially running) container. If the container is running, the listener starts
* receiving (matching) messages as soon as possible.
*
* @param listener message listener
* @param topics message listener topic
*/
public void addMessageListener(MessageListener listener, Collection<? extends Topic> topics) {
addListener(listener, topics);
lazyListen();
}
/**
* Adds a message listener to the (potentially running) container. If the container is running, the listener starts
* receiving (matching) messages as soon as possible.
*
* @param listener message listener
* @param topic message topic
*/
public void addMessageListener(MessageListener listener, Topic topic) {
addMessageListener(listener, Collections.singleton(topic));
}
/**
* Removes a message listener from the given topics. If the container is running, the listener stops receiving
* (matching) messages as soon as possible.
* <p>
* Note that this method obeys the Redis (p)unsubscribe semantics - meaning an empty/null collection will remove
* listener from all channels. Similarly a null listener will unsubscribe all listeners from the given topic.
*
* @param listener message listener
* @param topics message listener topics
*/
public void removeMessageListener(MessageListener listener, Collection<? extends Topic> topics) {
removeListener(listener, topics);
}
/**
* Removes a message listener from the from the given topic. If the container is running, the listener stops receiving
* (matching) messages as soon as possible.
* <p>
* Note that this method obeys the Redis (p)unsubscribe semantics - meaning an empty/null collection will remove
* listener from all channels. Similarly a null listener will unsubscribe all listeners from the given topic.
*
* @param listener message listener
* @param topic message topic
*/
public void removeMessageListener(MessageListener listener, Topic topic) {
removeMessageListener(listener, Collections.singleton(topic));
}
/**
* Removes the given message listener completely (from all topics). If the container is running, the listener stops
* receiving (matching) messages as soon as possible. Similarly a null listener will unsubscribe all listeners from
* the given topic.
*
* @param listener message listener
*/
public void removeMessageListener(MessageListener listener) {
removeMessageListener(listener, Collections.<Topic> emptySet());
}
private void initMapping(Map<? extends MessageListener, Collection<? extends Topic>> listeners) {
// stop the listener if currently running
if (isRunning()) {
subscriptionTask.cancel();
}
patternMapping.clear();
channelMapping.clear();
listenerTopics.clear();
if (!CollectionUtils.isEmpty(listeners)) {
for (Map.Entry<? extends MessageListener, Collection<? extends Topic>> entry : listeners.entrySet()) {
addListener(entry.getKey(), entry.getValue());
}
}
// resume activity
if (initialized) {
start();
}
}
/**
* Method inspecting whether listening for messages (and thus using a thread) is actually needed and triggering it.
*/
private void lazyListen() {
boolean debug = logger.isDebugEnabled();
boolean started = false;
if (isRunning()) {
if (!listening) {
synchronized (monitor) {
if (!listening) {
if (channelMapping.size() > 0 || patternMapping.size() > 0) {
subscriptionExecutor.execute(subscriptionTask);
listening = true;
started = true;
}
}
}
if (debug) {
if (started) {
logger.debug("Started listening for Redis messages");
} else {
logger.debug("Postpone listening for Redis messages until actual listeners are added");
}
}
}
}
}
private void addListener(MessageListener listener, Collection<? extends Topic> topics) {
Assert.notNull(listener, "a valid listener is required");
Assert.notEmpty(topics, "at least one topic is required");
List<byte[]> channels = new ArrayList<>(topics.size());
List<byte[]> patterns = new ArrayList<>(topics.size());
boolean trace = logger.isTraceEnabled();
// add listener mapping
Set<Topic> set = listenerTopics.get(listener);
if (set == null) {
set = new CopyOnWriteArraySet<>();
listenerTopics.put(listener, set);
}
set.addAll(topics);
for (Topic topic : topics) {
ByteArrayWrapper holder = new ByteArrayWrapper(serializer.serialize(topic.getTopic()));
if (topic instanceof ChannelTopic) {
Collection<MessageListener> collection = channelMapping.get(holder);
if (collection == null) {
collection = new CopyOnWriteArraySet<>();
channelMapping.put(holder, collection);
}
collection.add(listener);
channels.add(holder.getArray());
if (trace)
logger.trace("Adding listener '" + listener + "' on channel '" + topic.getTopic() + "'");
}
else if (topic instanceof PatternTopic) {
Collection<MessageListener> collection = patternMapping.get(holder);
if (collection == null) {
collection = new CopyOnWriteArraySet<>();
patternMapping.put(holder, collection);
}
collection.add(listener);
patterns.add(holder.getArray());
if (trace)
logger.trace("Adding listener '" + listener + "' for pattern '" + topic.getTopic() + "'");
}
else {
throw new IllegalArgumentException("Unknown topic type '" + topic.getClass() + "'");
}
}
// check the current listening state
if (listening) {
subscriptionTask.subscribeChannel(channels.toArray(new byte[channels.size()][]));
subscriptionTask.subscribePattern(patterns.toArray(new byte[patterns.size()][]));
}
}
private void removeListener(MessageListener listener, Collection<? extends Topic> topics) {
boolean trace = logger.isTraceEnabled();
// check stop listening case
if (listener == null && CollectionUtils.isEmpty(topics)) {
subscriptionTask.cancel();
return;
}
List<byte[]> channelsToRemove = new ArrayList<>();
List<byte[]> patternsToRemove = new ArrayList<>();
// check unsubscribe all topics case
if (CollectionUtils.isEmpty(topics)) {
Set<Topic> set = listenerTopics.remove(listener);
// listener not found, bail out
if (set == null) {
return;
}
topics = set;
}
for (Topic topic : topics) {
ByteArrayWrapper holder = new ByteArrayWrapper(serializer.serialize(topic.getTopic()));
if (topic instanceof ChannelTopic) {
remove(listener, topic, holder, channelMapping, channelsToRemove);
if (trace) {
String msg = (listener != null ? "listener '" + listener + "'" : "all listeners");
logger.trace("Removing " + msg + " from channel '" + topic.getTopic() + "'");
}
}
else if (topic instanceof PatternTopic) {
remove(listener, topic, holder, patternMapping, patternsToRemove);
if (trace) {
String msg = (listener != null ? "listener '" + listener + "'" : "all listeners");
logger.trace("Removing " + msg + " from pattern '" + topic.getTopic() + "'");
}
}
}
// double check whether there are still subscriptions available otherwise cancel the connection
// as most drivers forfeit the connection on unsubscribe
if (listenerTopics.isEmpty()) {
subscriptionTask.cancel();
}
// check the current listening state
else if (listening) {
subscriptionTask.unsubscribeChannel(channelsToRemove.toArray(new byte[channelsToRemove.size()][]));
subscriptionTask.unsubscribePattern(patternsToRemove.toArray(new byte[patternsToRemove.size()][]));
}
}
private void remove(MessageListener listener, Topic topic, ByteArrayWrapper holder,
Map<ByteArrayWrapper, Collection<MessageListener>> mapping, List<byte[]> topicToRemove) {
Collection<MessageListener> listeners = mapping.get(holder);
Collection<MessageListener> listenersToRemove = null;
if (listeners != null) {
// remove only one listener
if (listener != null) {
listeners.remove(listener);
listenersToRemove = Collections.singletonList(listener);
}
// no listener given - remove all of them
else {
listenersToRemove = listeners;
}
// start removing listeners
for (MessageListener messageListener : listenersToRemove) {
Set<Topic> topics = listenerTopics.get(messageListener);
if (topics != null) {
topics.remove(topic);
}
if (CollectionUtils.isEmpty(topics)) {
listenerTopics.remove(messageListener);
}
}
// if we removed everything, remove the empty holder collection
if (listener == null || listeners.isEmpty()) {
mapping.remove(holder);
topicToRemove.add(holder.getArray());
}
}
}
/**
* Handle subscription task exception. Will attempt to restart the subscription if the Exception is a connection
* failure (for example, Redis was restarted).
*
* @param ex Throwable exception
*/
protected void handleSubscriptionException(Throwable ex) {
listening = false;
subscriptionTask.closeConnection();
if (ex instanceof RedisConnectionFailureException) {
if (isRunning()) {
logger.error("Connection failure occurred. Restarting subscription task after " + recoveryInterval + " ms");
sleepBeforeRecoveryAttempt();
lazyListen();
}
} else {
logger.error("SubscriptionTask aborted with exception:", ex);
}
}
/**
* Sleep according to the specified recovery interval. Called between recovery attempts.
*/
protected void sleepBeforeRecoveryAttempt() {
if (this.recoveryInterval > 0) {
try {
Thread.sleep(this.recoveryInterval);
} catch (InterruptedException interEx) {
logger.debug("Thread interrupted while sleeping the recovery interval");
Thread.currentThread().interrupt();
}
}
}
/**
* Runnable used for Redis subscription. Implemented as a dedicated class to provide as many hints as possible to the
* underlying thread pool.
*
* @author Costin Leau
*/
private class SubscriptionTask implements SchedulingAwareRunnable {
/**
* Runnable used, on a parallel thread, to do the initial pSubscribe. This is required since, during initialization,
* both subscribe and pSubscribe might be needed but since the first call is blocking, the second call needs to
* executed in parallel.
*
* @author Costin Leau
*/
private class PatternSubscriptionTask implements SchedulingAwareRunnable {
private long WAIT = 500;
private long ROUNDS = 3;
public boolean isLongLived() {
return false;
}
public void run() {
// wait for subscription to be initialized
boolean done = false;
// wait 3 rounds for subscription to be initialized
for (int i = 0; i < ROUNDS && !done; i++) {
if (connection != null) {
synchronized (localMonitor) {
if (connection.isSubscribed()) {
done = true;
connection.getSubscription().pSubscribe(unwrap(patternMapping.keySet()));
} else {
try {
Thread.sleep(WAIT);
} catch (InterruptedException ex) {
Thread.currentThread().interrupt();
return;
}
}
}
}
}
}
}
private volatile @Nullable RedisConnection connection;
private boolean subscriptionTaskRunning = false;
private final Object localMonitor = new Object();
private long subscriptionWait = TimeUnit.SECONDS.toMillis(5);
public boolean isLongLived() {
return true;
}
public void run() {
synchronized (localMonitor) {
subscriptionTaskRunning = true;
}
try {
connection = connectionFactory.getConnection();
if (connection.isSubscribed()) {
throw new IllegalStateException("Retrieved connection is already subscribed; aborting listening");
}
boolean asyncConnection = ConnectionUtils.isAsync(connectionFactory);
// NB: sync drivers' Xsubscribe calls block, so we notify the RDMLC before performing the actual subscription.
if (!asyncConnection) {
synchronized (monitor) {
monitor.notify();
}
}
SubscriptionPresentCondition subscriptionPresent = eventuallyPerformSubscription();
if (asyncConnection) {
SpinBarrier.waitFor(subscriptionPresent, getMaxSubscriptionRegistrationWaitingTime());
synchronized (monitor) {
monitor.notify();
}
}
} catch (Throwable t) {
handleSubscriptionException(t);
} finally {
// this block is executed once the subscription thread has ended, this may or may not mean
// the connection has been unsubscribed, depending on driver
synchronized (localMonitor) {
subscriptionTaskRunning = false;
localMonitor.notify();
}
}
}
/**
* Performs a potentially asynchronous registration of a subscription.
*
* @return #SubscriptionPresentCondition that can serve as a handle to check whether the subscription is ready.
*/
private SubscriptionPresentCondition eventuallyPerformSubscription() {
SubscriptionPresentCondition condition = null;
if (channelMapping.isEmpty()) {
condition = new PatternSubscriptionPresentCondition();
connection.pSubscribe(new DispatchMessageListener(), unwrap(patternMapping.keySet()));
} else {
if (patternMapping.isEmpty()) {
condition = new SubscriptionPresentCondition();
} else {
// schedule the rest of the subscription
subscriptionExecutor.execute(new PatternSubscriptionTask());
condition = new PatternSubscriptionPresentCondition();
}
connection.subscribe(new DispatchMessageListener(), unwrap(channelMapping.keySet()));
}
return condition;
}
/**
* Checks whether the current connection has an associated subscription.
*
* @author Thomas Darimont
*/
private class SubscriptionPresentCondition implements Condition {
public boolean passes() {
return connection.isSubscribed();
}
}
/**
* Checks whether the current connection has an associated pattern subscription.
*
* @author Thomas Darimont
* @see org.springframework.data.redis.listener.RedisMessageListenerContainer.SubscriptionTask.SubscriptionPresentTestCondition
*/
private class PatternSubscriptionPresentCondition extends SubscriptionPresentCondition {
@Override
public boolean passes() {
return super.passes() && !CollectionUtils.isEmpty(connection.getSubscription().getPatterns());
}
}
private byte[][] unwrap(Collection<ByteArrayWrapper> holders) {
if (CollectionUtils.isEmpty(holders)) {
return new byte[0][];
}
byte[][] unwrapped = new byte[holders.size()][];
int index = 0;
for (ByteArrayWrapper arrayHolder : holders) {
unwrapped[index++] = arrayHolder.getArray();
}
return unwrapped;
}
void cancel() {
if (!listening || connection == null) {
return;
}
listening = false;
if (logger.isTraceEnabled()) {
logger.trace("Cancelling Redis subscription...");
}
Subscription sub = connection.getSubscription();
if (sub != null) {
synchronized (localMonitor) {
if (logger.isTraceEnabled()) {
logger.trace("Unsubscribing from all channels");
}
try {
sub.close();
} catch (Exception e) {
logger.warn("Unable to unsubscribe from subscriptions", e);
}
if (subscriptionTaskRunning) {
try {
localMonitor.wait(subscriptionWait);
} catch (InterruptedException e) {
// Stop waiting
Thread.currentThread().interrupt();
}
}
if (!subscriptionTaskRunning) {
closeConnection();
} else {
logger.warn("Unable to close connection. Subscription task still running");
}
}
}
}
void closeConnection() {
if (connection != null) {
logger.trace("Closing connection");
try {
connection.close();
} catch (Exception e) {
logger.warn("Error closing subscription connection", e);
}
connection = null;
}
}
void subscribeChannel(byte[]... channels) {
if (channels != null && channels.length > 0) {
if (connection != null) {
synchronized (localMonitor) {
Subscription sub = connection.getSubscription();
if (sub != null) {
sub.subscribe(channels);
}
}
}
}
}
void subscribePattern(byte[]... patterns) {
if (patterns != null && patterns.length > 0) {
if (connection != null) {
synchronized (localMonitor) {
Subscription sub = connection.getSubscription();
if (sub != null) {
sub.pSubscribe(patterns);
}
}
}
}
}
void unsubscribeChannel(byte[]... channels) {
if (channels != null && channels.length > 0) {
if (connection != null) {
synchronized (localMonitor) {
Subscription sub = connection.getSubscription();
if (sub != null) {
sub.unsubscribe(channels);
}
}
}
}
}
void unsubscribePattern(byte[]... patterns) {
if (patterns != null && patterns.length > 0) {
if (connection != null) {
synchronized (localMonitor) {
Subscription sub = connection.getSubscription();
if (sub != null) {
sub.pUnsubscribe(patterns);
}
}
}
}
}
}
/**
* Actual message dispatcher/multiplexer.
*
* @author Costin Leau
*/
private class DispatchMessageListener implements MessageListener {
@Override
public void onMessage(Message message, @Nullable byte[] pattern) {
Collection<MessageListener> listeners = null;
// if it's a pattern, disregard channel
if (pattern != null && pattern.length > 0) {
listeners = patternMapping.get(new ByteArrayWrapper(pattern));
} else {
pattern = null;
// do channel matching first
listeners = channelMapping.get(new ByteArrayWrapper(message.getChannel()));
}
if (!CollectionUtils.isEmpty(listeners)) {
dispatchMessage(listeners, message, pattern);
}
}
}
private void dispatchMessage(Collection<MessageListener> listeners, final Message message, final byte[] pattern) {
final byte[] source = (pattern != null ? pattern.clone() : message.getChannel());
for (final MessageListener messageListener : listeners) {
taskExecutor.execute(() -> processMessage(messageListener, message, source));
}
}
/**
* Specify the interval between recovery attempts, in <b>milliseconds</b>. The default is 5000 ms, that is, 5 seconds.
*
* @see #handleSubscriptionException
*/
public void setRecoveryInterval(long recoveryInterval) {
this.recoveryInterval = recoveryInterval;
}
public long getMaxSubscriptionRegistrationWaitingTime() {
return maxSubscriptionRegistrationWaitingTime;