Class SimpleBrokerMessageHandler

java.lang.Object

org.springframework.messaging.simp.broker.AbstractBrokerMessageHandler

org.springframework.messaging.simp.broker.SimpleBrokerMessageHandler

All Implemented Interfaces:

Aware, ApplicationEventPublisherAware, Lifecycle, Phased, SmartLifecycle, MessageHandler

public class SimpleBrokerMessageHandler
extends AbstractBrokerMessageHandler

A "simple" message broker that recognizes the message types defined in SimpMessageType, keeps track of subscriptions with the help of a SubscriptionRegistry, and sends messages to subscribers.

Since:

4.0

Author:

Rossen Stoyanchev, Juergen Hoeller, Sam Brannen

Field Summary

Fields inherited from class AbstractBrokerMessageHandler

logger

Fields inherited from interface SmartLifecycle

DEFAULT_PHASE

Constructor Summary

Constructors

Constructor	Description
SimpleBrokerMessageHandler(SubscribableChannel clientInboundChannel, MessageChannel clientOutboundChannel, SubscribableChannel brokerChannel, Collection<String> destinationPrefixes)	Create a SimpleBrokerMessageHandler instance with the given message channels and destination prefixes.

Method Summary

Modifier and Type	Method	Description
@Nullable MessageHeaderInitializer	getHeaderInitializer()	Return the configured header initializer.
long @Nullable []	getHeartbeatValue()	The configured value for the heart-beat settings.
SubscriptionRegistry	getSubscriptionRegistry()
@Nullable TaskScheduler	getTaskScheduler()	Return the configured TaskScheduler.
protected void	handleMessageInternal(Message<?> message)
protected void	sendMessageToSubscribers(@Nullable String destination, Message<?> message)
void	setCacheLimit(@Nullable Integer cacheLimit)	When configured, the specified cache limit is passed down to the underlying SubscriptionRegistry, overriding any default there.
void	setHeaderInitializer(@Nullable MessageHeaderInitializer headerInitializer)	Configure a MessageHeaderInitializer to apply to the headers of all messages sent to the client outbound channel.
void	setHeartbeatValue(long @Nullable [] heartbeat)	Configure the value for the heart-beat settings.
void	setPathMatcher(@Nullable PathMatcher pathMatcher)	When configured, the given PathMatcher is passed down to the underlying SubscriptionRegistry to use for matching destination to subscriptions.
void	setSelectorHeaderName(@Nullable String selectorHeaderName)	Configure the name of a header that a subscription message can have for the purpose of filtering messages matched to the subscription.
void	setSubscriptionRegistry(SubscriptionRegistry subscriptionRegistry)	Configure a custom SubscriptionRegistry to use for storing subscriptions.
void	setTaskScheduler(@Nullable TaskScheduler taskScheduler)	Configure the TaskScheduler to use for providing heartbeat support.
void	startInternal()
void	stopInternal()
String	toString()

Methods inherited from class AbstractBrokerMessageHandler

checkDestinationPrefix, getApplicationEventPublisher, getBrokerChannel, getClientInboundChannel, getClientOutboundChannel, getClientOutboundChannelForSession, getDestinationPrefixes, getPhase, handleMessage, isAutoStartup, isBrokerAvailable, isPreservePublishOrder, isRunning, publishBrokerAvailableEvent, publishBrokerUnavailableEvent, setApplicationEventPublisher, setAutoStartup, setPhase, setPreservePublishOrder, setUserDestinationPredicate, start, stop, stop

Methods inherited from class Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Methods inherited from interface SmartLifecycle

isPauseable

Constructor Details

SimpleBrokerMessageHandler

public SimpleBrokerMessageHandler(SubscribableChannel clientInboundChannel,
 MessageChannel clientOutboundChannel,
 SubscribableChannel brokerChannel,
 Collection<String> destinationPrefixes)

Create a SimpleBrokerMessageHandler instance with the given message channels and destination prefixes.

Parameters:

clientInboundChannel - the channel for receiving messages from clients (for example, WebSocket clients)

clientOutboundChannel - the channel for sending messages to clients (for example, WebSocket clients)

brokerChannel - the channel for the application to send messages to the broker

destinationPrefixes - prefixes to use to filter out messages

Method Details

setSubscriptionRegistry

public void setSubscriptionRegistry(SubscriptionRegistry subscriptionRegistry)

Configure a custom SubscriptionRegistry to use for storing subscriptions.

NOTE: If the custom registry is not an instance of DefaultSubscriptionRegistry, the configured PathMatcher, cache limit, and selector header name are not used and must be configured directly on the custom registry.

getSubscriptionRegistry

public SubscriptionRegistry getSubscriptionRegistry()

setPathMatcher

public void setPathMatcher(@Nullable PathMatcher pathMatcher)

When configured, the given PathMatcher is passed down to the underlying SubscriptionRegistry to use for matching destination to subscriptions.

Default is a standard AntPathMatcher.

Setting this property has no effect if the underlying SubscriptionRegistry is not an instance of DefaultSubscriptionRegistry.

Since:

4.1

See Also:

• setSubscriptionRegistry(SubscriptionRegistry)
• DefaultSubscriptionRegistry.setPathMatcher(PathMatcher)
• AntPathMatcher

setCacheLimit

public void setCacheLimit(@Nullable Integer cacheLimit)

When configured, the specified cache limit is passed down to the underlying SubscriptionRegistry, overriding any default there.

With a standard DefaultSubscriptionRegistry, the default cache limit is 1024.

Setting this property has no effect if the underlying SubscriptionRegistry is not an instance of DefaultSubscriptionRegistry.

Since:

4.3.2

See Also:

• setSubscriptionRegistry(SubscriptionRegistry)
• DefaultSubscriptionRegistry.setCacheLimit(int)
• DefaultSubscriptionRegistry.DEFAULT_CACHE_LIMIT

setSelectorHeaderName

public void setSelectorHeaderName(@Nullable String selectorHeaderName)

Configure the name of a header that a subscription message can have for the purpose of filtering messages matched to the subscription.

The header value is expected to be a Spring Expression Language (SpEL) boolean expression to be applied to the headers of messages matched to the subscription.

For example:

headers.foo == 'bar'

By default the selector header name is set to null which disables this feature. You can set it to "selector" or a different name to enable support for a selector header.

Setting this property has no effect if the underlying SubscriptionRegistry is not an instance of DefaultSubscriptionRegistry.

Parameters:

selectorHeaderName - the name to use for a selector header, or null or blank to disable selector header support

Since:

4.3.17

See Also:

• setSubscriptionRegistry(SubscriptionRegistry)
• DefaultSubscriptionRegistry.setSelectorHeaderName(String)

setTaskScheduler

public void setTaskScheduler(@Nullable TaskScheduler taskScheduler)

Configure the TaskScheduler to use for providing heartbeat support. Setting this property also sets the heartbeatValue to "10000, 10000".

By default this is not set.

Since:

4.2

getTaskScheduler

public @Nullable TaskScheduler getTaskScheduler()

Return the configured TaskScheduler.

Since:

4.2

setHeartbeatValue

public void setHeartbeatValue(long @Nullable [] heartbeat)

Configure the value for the heart-beat settings. The first number represents how often the server will write or send a heartbeat. The second is how often the client should write. 0 means no heartbeats.

By default this is set to "0, 0" unless the taskScheduler in which case the default becomes "10000,10000" (in milliseconds).

Since:

4.2

getHeartbeatValue

public long @Nullable [] getHeartbeatValue()

The configured value for the heart-beat settings.

Since:

4.2

setHeaderInitializer

public void setHeaderInitializer(@Nullable MessageHeaderInitializer headerInitializer)

Configure a MessageHeaderInitializer to apply to the headers of all messages sent to the client outbound channel.

By default this property is not set.

Since:

4.1

getHeaderInitializer

public @Nullable MessageHeaderInitializer getHeaderInitializer()

Return the configured header initializer.

Since:

4.1

startInternal

public void startInternal()

Overrides:

startInternal in class AbstractBrokerMessageHandler

stopInternal

public void stopInternal()

Overrides:

stopInternal in class AbstractBrokerMessageHandler

handleMessageInternal

protected void handleMessageInternal(Message<?> message)

Specified by:

handleMessageInternal in class AbstractBrokerMessageHandler

sendMessageToSubscribers

protected void sendMessageToSubscribers(@Nullable String destination,
 Message<?> message)

toString

public String toString()

Overrides:

toString in class Object