Expose DefaultSubscriptionRegistry's cache limit through SimpleBrokerMessageHandler and MessageBrokerRegistry

Issue: SPR-14516

spring-messaging/src/main/java/org/springframework/messaging/simp/broker/DefaultSubscriptionRegistry.java

@@ -50,7 +50,7 @@ import org.springframework.util.PathMatcher;
  * in memory and uses a {@link org.springframework.util.PathMatcher PathMatcher}
  * for matching destinations.
  *
- * <p>As of 4.2 this class supports a {@link #setSelectorHeaderName selector}
+ * <p>As of 4.2, this class supports a {@link #setSelectorHeaderName selector}
  * header on subscription messages with Spring EL expressions evaluated against
  * the headers to filter out messages in addition to destination matching.
  *
@@ -65,11 +65,10 @@ public class DefaultSubscriptionRegistry extends AbstractSubscriptionRegistry {
 	public static final int DEFAULT_CACHE_LIMIT = 1024;
 
 
-	/** The maximum number of entries in the cache */
-	private volatile int cacheLimit = DEFAULT_CACHE_LIMIT;
-
 	private PathMatcher pathMatcher = new AntPathMatcher();
 
+	private volatile int cacheLimit = DEFAULT_CACHE_LIMIT;
+
 	private String selectorHeaderName = "selector";
 
 	private volatile boolean selectorHeaderInUse = false;
@@ -82,32 +81,32 @@ public class DefaultSubscriptionRegistry extends AbstractSubscriptionRegistry {
 
 
 	/**
-	 * Specify the maximum number of entries for the resolved destination cache.
+	 * Specify the {@link PathMatcher} to use.
-	 * Default is 1024.
 	 */
-	public void setCacheLimit(int cacheLimit) {
+	public void setPathMatcher(PathMatcher pathMatcher) {
-		this.cacheLimit = cacheLimit;
+		this.pathMatcher = pathMatcher;
 	}
 
 	/**
-	 * Return the maximum number of entries for the resolved destination cache.
+	 * Return the configured {@link PathMatcher}.
 	 */
-	public int getCacheLimit() {
+	public PathMatcher getPathMatcher() {
-		return this.cacheLimit;
+		return this.pathMatcher;
 	}
 
 	/**
-	 * Specify the {@link PathMatcher} to use.
+	 * Specify the maximum number of entries for the resolved destination cache.
+	 * Default is 1024.
 	 */
-	public void setPathMatcher(PathMatcher pathMatcher) {
+	public void setCacheLimit(int cacheLimit) {
-		this.pathMatcher = pathMatcher;
+		this.cacheLimit = cacheLimit;
 	}
 
 	/**
-	 * Return the configured {@link PathMatcher}.
+	 * Return the maximum number of entries for the resolved destination cache.
 	 */
-	public PathMatcher getPathMatcher() {
+	public int getCacheLimit() {
-		return this.pathMatcher;
+		return this.cacheLimit;
 	}
 
 	/**
@@ -123,12 +122,13 @@ public class DefaultSubscriptionRegistry extends AbstractSubscriptionRegistry {
 	 * @since 4.2
 	 */
 	public void setSelectorHeaderName(String selectorHeaderName) {
-		Assert.notNull(selectorHeaderName);
+		Assert.notNull(selectorHeaderName, "'selectorHeaderName' must not be null");
 		this.selectorHeaderName = selectorHeaderName;
 	}
 
 	/**
 	 * Return the name for the selector header.
+	 * @since 4.2
 	 */
 	public String getSelectorHeaderName() {
 		return this.selectorHeaderName;

spring-messaging/src/main/java/org/springframework/messaging/simp/broker/SimpleBrokerMessageHandler.java

@@ -42,6 +42,7 @@ import org.springframework.util.PathMatcher;
  * {@link SubscriptionRegistry} and sends messages to subscribers.
  *
  * @author Rossen Stoyanchev
+ * @author Juergen Hoeller
  * @since 4.0
  */
 public class SimpleBrokerMessageHandler extends AbstractBrokerMessageHandler {
@@ -54,6 +55,8 @@ public class SimpleBrokerMessageHandler extends AbstractBrokerMessageHandler {
 
 	private PathMatcher pathMatcher;
 
+	private Integer cacheLimit;
+
 	private TaskScheduler taskScheduler;
 
 	private long[] heartbeatValue;
@@ -90,14 +93,7 @@ public class SimpleBrokerMessageHandler extends AbstractBrokerMessageHandler {
 		Assert.notNull(subscriptionRegistry, "SubscriptionRegistry must not be null");
 		this.subscriptionRegistry = subscriptionRegistry;
 		initPathMatcherToUse();
-	}
+		initCacheLimitToUse();
-
-	private void initPathMatcherToUse() {
-		if (this.pathMatcher != null) {
-			if (this.subscriptionRegistry instanceof DefaultSubscriptionRegistry) {
-				((DefaultSubscriptionRegistry) this.subscriptionRegistry).setPathMatcher(this.pathMatcher);
-			}
-		}
 	}
 
 	public SubscriptionRegistry getSubscriptionRegistry() {
@@ -105,14 +101,46 @@ public class SimpleBrokerMessageHandler extends AbstractBrokerMessageHandler {
 	}
 
 	/**
-	 * When configured, the given PathMatcher is passed down to the
+	 * When configured, the given PathMatcher is passed down to the underlying
 	 * SubscriptionRegistry to use for matching destination to subscriptions.
+	 * <p>Default is a standard {@link org.springframework.util.AntPathMatcher}.
+	 * @since 4.1
+	 * @see #setSubscriptionRegistry
+	 * @see DefaultSubscriptionRegistry#setPathMatcher
+	 * @see org.springframework.util.AntPathMatcher
 	 */
 	public void setPathMatcher(PathMatcher pathMatcher) {
 		this.pathMatcher = pathMatcher;
 		initPathMatcherToUse();
 	}
 
+	private void initPathMatcherToUse() {
+		if (this.pathMatcher != null && this.subscriptionRegistry instanceof DefaultSubscriptionRegistry) {
+			((DefaultSubscriptionRegistry) this.subscriptionRegistry).setPathMatcher(this.pathMatcher);
+		}
+	}
+
+	/**
+	 * When configured, the specified cache limit is passed down to the
+	 * underlying SubscriptionRegistry, overriding any default there.
+	 * <p>With a standard {@link DefaultSubscriptionRegistry}, the default
+	 * cache limit is 1024.
+	 * @since 4.3.2
+	 * @see #setSubscriptionRegistry
+	 * @see DefaultSubscriptionRegistry#setCacheLimit
+	 * @see DefaultSubscriptionRegistry#DEFAULT_CACHE_LIMIT
+	 */
+	public void setCacheLimit(Integer cacheLimit) {
+		this.cacheLimit = cacheLimit;
+		initCacheLimitToUse();
+	}
+
+	private void initCacheLimitToUse() {
+		if (this.cacheLimit != null && this.subscriptionRegistry instanceof DefaultSubscriptionRegistry) {
+			((DefaultSubscriptionRegistry) this.subscriptionRegistry).setCacheLimit(this.cacheLimit);
+		}
+	}
+
 	/**
 	 * Configure the {@link org.springframework.scheduling.TaskScheduler} to
 	 * use for providing heartbeat support. Setting this property also sets the
@@ -130,6 +158,7 @@ public class SimpleBrokerMessageHandler extends AbstractBrokerMessageHandler {
 
 	/**
 	 * Return the configured TaskScheduler.
+	 * @since 4.2
 	 */
 	public TaskScheduler getTaskScheduler() {
 		return this.taskScheduler;
@@ -151,6 +180,7 @@ public class SimpleBrokerMessageHandler extends AbstractBrokerMessageHandler {
 
 	/**
 	 * The configured value for the heart-beat settings.
+	 * @since 4.2
 	 */
 	public long[] getHeartbeatValue() {
 		return this.heartbeatValue;
@@ -160,6 +190,7 @@ public class SimpleBrokerMessageHandler extends AbstractBrokerMessageHandler {
 	 * Configure a {@link MessageHeaderInitializer} to apply to the headers
 	 * of all messages sent to the client outbound channel.
 	 * <p>By default this property is not set.
+	 * @since 4.1
 	 */
 	public void setHeaderInitializer(MessageHeaderInitializer headerInitializer) {
 		this.headerInitializer = headerInitializer;
@@ -167,6 +198,7 @@ public class SimpleBrokerMessageHandler extends AbstractBrokerMessageHandler {
 
 	/**
 	 * Return the configured header initializer.
+	 * @since 4.1
 	 */
 	public MessageHeaderInitializer getHeaderInitializer() {
 		return this.headerInitializer;

spring-messaging/src/main/java/org/springframework/messaging/simp/config/AbstractMessageBrokerConfiguration.java

@@ -143,7 +143,7 @@ public abstract class AbstractMessageBrokerConfiguration implements ApplicationC
 	}
 
 	/**
-	 * A hook for sub-classes to customize the message channel for inbound messages
+	 * A hook for subclasses to customize the message channel for inbound messages
 	 * from WebSocket clients.
 	 */
 	protected void configureClientInboundChannel(ChannelRegistration registration) {
@@ -176,7 +176,7 @@ public abstract class AbstractMessageBrokerConfiguration implements ApplicationC
 	}
 
 	/**
-	 * A hook for sub-classes to customize the message channel for messages from
+	 * A hook for subclasses to customize the message channel for messages from
 	 * the application or message broker to WebSocket clients.
 	 */
 	protected void configureClientOutboundChannel(ChannelRegistration registration) {
@@ -224,7 +224,7 @@ public abstract class AbstractMessageBrokerConfiguration implements ApplicationC
 	}
 
 	/**
-	 * A hook for sub-classes to customize message broker configuration through the
+	 * A hook for subclasses to customize message broker configuration through the
 	 * provided {@link MessageBrokerRegistry} instance.
 	 */
 	protected void configureMessageBroker(MessageBrokerRegistry registry) {
@@ -253,7 +253,7 @@ public abstract class AbstractMessageBrokerConfiguration implements ApplicationC
 		addReturnValueHandlers(returnValueHandlers);
 		handler.setCustomReturnValueHandlers(returnValueHandlers);
 
-		PathMatcher pathMatcher = this.getBrokerRegistry().getPathMatcher();
+		PathMatcher pathMatcher = getBrokerRegistry().getPathMatcher();
 		if (pathMatcher != null) {
 			handler.setPathMatcher(pathMatcher);
 		}
@@ -261,7 +261,7 @@ public abstract class AbstractMessageBrokerConfiguration implements ApplicationC
 	}
 
 	/**
-	 * Protected method for plugging in a custom sub-class of
+	 * Protected method for plugging in a custom subclass of
 	 * {@link org.springframework.messaging.simp.annotation.support.SimpAnnotationMethodMessageHandler
 	 * SimpAnnotationMethodMessageHandler}.
 	 * @since 4.2
@@ -324,7 +324,6 @@ public abstract class AbstractMessageBrokerConfiguration implements ApplicationC
 	}
 
 	// Expose alias for 4.1 compatibility
-
 	@Bean(name={"messageBrokerTaskScheduler", "messageBrokerSockJsTaskScheduler"})
 	public ThreadPoolTaskScheduler messageBrokerTaskScheduler() {
 		ThreadPoolTaskScheduler scheduler = new ThreadPoolTaskScheduler();
@@ -461,6 +460,7 @@ public abstract class AbstractMessageBrokerConfiguration implements ApplicationC
 
 	}
 
+
 	private class NoOpBrokerMessageHandler extends AbstractBrokerMessageHandler {
 
 		public NoOpBrokerMessageHandler() {

spring-messaging/src/main/java/org/springframework/messaging/simp/config/MessageBrokerRegistry.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2015 the original author or authors.
+ * Copyright 2002-2016 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.
@@ -51,6 +51,8 @@ public class MessageBrokerRegistry {
 
 	private PathMatcher pathMatcher;
 
+	private Integer cacheLimit;
+
 
 	public MessageBrokerRegistry(SubscribableChannel clientInboundChannel, MessageChannel clientOutboundChannel) {
 		Assert.notNull(clientInboundChannel);
@@ -96,6 +98,16 @@ public class MessageBrokerRegistry {
 		return this.brokerChannelRegistration;
 	}
 
+	protected String getUserDestinationBroadcast() {
+		return (this.brokerRelayRegistration != null ?
+				this.brokerRelayRegistration.getUserDestinationBroadcast() : null);
+	}
+
+	protected String getUserRegistryBroadcast() {
+		return (this.brokerRelayRegistration != null ?
+				this.brokerRelayRegistration.getUserRegistryBroadcast() : null);
+	}
+
 	/**
 	 * Configure one or more prefixes to filter destinations targeting application
 	 * annotated methods. For example destinations prefixed with "/app" may be
@@ -137,16 +149,6 @@ public class MessageBrokerRegistry {
 		return this.userDestinationPrefix;
 	}
 
-	protected String getUserDestinationBroadcast() {
-		return (this.brokerRelayRegistration != null ?
-				this.brokerRelayRegistration.getUserDestinationBroadcast() : null);
-	}
-
-	protected String getUserRegistryBroadcast() {
-		return (this.brokerRelayRegistration != null ?
-				this.brokerRelayRegistration.getUserRegistryBroadcast() : null);
-	}
-
 	/**
 	 * Configure the PathMatcher to use to match the destinations of incoming
 	 * messages to {@code @MessageMapping} and {@code @SubscribeMapping} methods.
@@ -162,6 +164,7 @@ public class MessageBrokerRegistry {
 	 * <p>When the simple broker is enabled, the PathMatcher configured here is
 	 * also used to match message destinations when brokering messages.
 	 * @since 4.1
+	 * @see org.springframework.messaging.simp.broker.DefaultSubscriptionRegistry#setPathMatcher
 	 */
 	public MessageBrokerRegistry setPathMatcher(PathMatcher pathMatcher) {
 		this.pathMatcher = pathMatcher;
@@ -172,6 +175,18 @@ public class MessageBrokerRegistry {
 		return this.pathMatcher;
 	}
 
+	/**
+	 * Configure the cache limit to apply for registrations with the broker.
+	 * <p>This is currently only applied for the destination cache in the
+	 * subscription registry. The default cache limit there is 1024.
+	 * @since 4.3.2
+	 * @see org.springframework.messaging.simp.broker.DefaultSubscriptionRegistry#setCacheLimit
+	 */
+	public MessageBrokerRegistry setCacheLimit(int cacheLimit) {
+		this.cacheLimit = cacheLimit;
+		return this;
+	}
+
 
 	protected SimpleBrokerMessageHandler getSimpleBroker(SubscribableChannel brokerChannel) {
 		if (this.simpleBrokerRegistration == null && this.brokerRelayRegistration == null) {
@@ -180,6 +195,7 @@ public class MessageBrokerRegistry {
 		if (this.simpleBrokerRegistration != null) {
 			SimpleBrokerMessageHandler handler = this.simpleBrokerRegistration.getMessageHandler(brokerChannel);
 			handler.setPathMatcher(this.pathMatcher);
+			handler.setCacheLimit(this.cacheLimit);
 			return handler;
 		}
 		return null;

spring-messaging/src/test/java/org/springframework/messaging/simp/config/MessageBrokerConfigurationTests.java

@@ -16,9 +16,6 @@
 
 package org.springframework.messaging.simp.config;
 
-import static org.junit.Assert.*;
-import static org.mockito.Mockito.*;
-
 import java.util.ArrayList;
 import java.util.Iterator;
 import java.util.List;
@@ -73,6 +70,9 @@ import org.springframework.validation.Errors;
 import org.springframework.validation.Validator;
 import org.springframework.validation.beanvalidation.OptionalValidatorFactoryBean;
 
+import static org.junit.Assert.*;
+import static org.mockito.Mockito.*;
+
 /**
  * Test fixture for {@link AbstractMessageBrokerConfiguration}.
  *
@@ -392,6 +392,13 @@ public class MessageBrokerConfigurationTests {
 		assertEquals(false, new DirectFieldAccessor(resolver).getPropertyValue("keepLeadingSlash"));
 	}
 
+	@Test
+	public void customCacheLimit() {
+		SimpleBrokerMessageHandler broker = this.customContext.getBean(SimpleBrokerMessageHandler.class);
+		DefaultSubscriptionRegistry registry = (DefaultSubscriptionRegistry) broker.getSubscriptionRegistry();
+		assertEquals(8192, registry.getCacheLimit());
+	}
+
 	@Test
 	public void userBroadcasts() throws Exception {
 		SimpUserRegistry userRegistry = this.brokerRelayContext.getBean(SimpUserRegistry.class);
@@ -441,6 +448,7 @@ public class MessageBrokerConfigurationTests {
 		}
 	}
 
+
 	static class BaseTestMessageBrokerConfig extends AbstractMessageBrokerConfiguration {
 
 		@Override
@@ -449,6 +457,7 @@ public class MessageBrokerConfigurationTests {
 		}
 	}
 
+
 	@SuppressWarnings("unused")
 	@Configuration
 	static class SimpleBrokerConfig extends BaseTestMessageBrokerConfig {
@@ -477,6 +486,7 @@ public class MessageBrokerConfigurationTests {
 		}
 	}
 
+
 	@Configuration
 	static class BrokerRelayConfig extends SimpleBrokerConfig {
 
@@ -488,10 +498,12 @@ public class MessageBrokerConfigurationTests {
 		}
 	}
 
+
 	@Configuration
 	static class DefaultConfig extends BaseTestMessageBrokerConfig {
 	}
 
+
 	@Configuration
 	static class CustomConfig extends BaseTestMessageBrokerConfig {
 
@@ -525,6 +537,7 @@ public class MessageBrokerConfigurationTests {
 			registry.configureBrokerChannel().setInterceptors(this.interceptor, this.interceptor, this.interceptor);
 			registry.configureBrokerChannel().taskExecutor().corePoolSize(31).maxPoolSize(32).keepAliveSeconds(33).queueCapacity(34);
 			registry.setPathMatcher(new AntPathMatcher(".")).enableSimpleBroker("/topic", "/queue");
+			registry.setCacheLimit(8192);
 		}
 	}
 
@@ -540,6 +553,7 @@ public class MessageBrokerConfigurationTests {
 		}
 	}
 
+
 	private static class TestValidator implements Validator {
 
 		@Override
@@ -552,6 +566,7 @@ public class MessageBrokerConfigurationTests {
 		}
 	}
 
+
 	@SuppressWarnings("serial")
 	private static class CustomThreadPoolTaskExecutor extends ThreadPoolTaskExecutor {
 	}