GH-9683: Bring back controlBus() API

Fixes: #9683

Since we don't support SpEL-based Control Bus functionality anymore,
there is no need to keep separate `controlBusOnRegistry()`

* In all DSLs Deprecate `controlBusOnRegistry()` and restore `controlBus()` which is now fully based
on the `ControlBusCommandRegistry`
* Deprecate now out of use `<control-bus use-registry="">` attribute
* Fix `ControlBusParser` to not deal with `use-registry` attribute anymore
* Remove deprecated before `ExpressionControlBusFactoryBean` and `ExpressionCommandMessageProcessor`
* Remove `use-registry` from test configs
* Fix `ControlBusChainTests` to rely on a new Control Bus functionality

Author: artembilan

spring-integration-core/src/main/java/org/springframework/integration/config/ExpressionControlBusFactoryBean.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2024 the original author or authors.
+ * Copyright 2002-2025 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.
@@ -32,18 +32,8 @@
 public class ControlBusParser extends AbstractConsumerEndpointParser {
 
 	@Override
-	@SuppressWarnings("removal")
 	protected BeanDefinitionBuilder parseHandler(Element element, ParserContext parserContext) {
 		BeanDefinitionBuilder builder = BeanDefinitionBuilder.genericBeanDefinition(ControlBusFactoryBean.class);
-		if (Boolean.FALSE.equals(Boolean.parseBoolean(element.getAttribute("use-registry")))) {
-			builder = BeanDefinitionBuilder.genericBeanDefinition(
-					org.springframework.integration.config.ExpressionControlBusFactoryBean.class);
-			parserContext.getReaderContext()
-					.warning("The 'ExpressionControlBusFactoryBean' for '<control-bus>' is deprecated (for removal) " +
-							"in favor of 'ControlBusFactoryBean'. " +
-							"Set 'use-registry' attribute to 'true' to switch to a new functionality.",
-							element);
-		}
 		IntegrationNamespaceUtils.setValueIfAttributeDefined(builder, element, "send-timeout");
 		IntegrationNamespaceUtils.setValueIfAttributeDefined(builder, element, "order");
 		return builder;

spring-integration-core/src/main/java/org/springframework/integration/config/xml/ControlBusParser.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2019-2024 the original author or authors.
+ * Copyright 2019-2025 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.
@@ -518,10 +518,12 @@ public B wireTap(WireTapSpec wireTapSpec) {
 	 * at the current {@link IntegrationFlow} chain position.
 	 * @return the current {@link BaseIntegrationFlowDefinition}.
 	 * @since 6.4
+	 * @deprecated since 6.5 in favor of {@link #controlBus()}
 	 * @see ControlBusMessageProcessor
 	 */
+	@Deprecated(since = "6.5", forRemoval = true)
 	public B controlBusOnRegistry() {
-		return controlBusOnRegistry(null);
+		return controlBus();
 	}
 
 	/**
@@ -530,20 +532,20 @@ public B controlBusOnRegistry() {
 	 * @param endpointConfigurer the {@link Consumer} to accept integration endpoint options.
 	 * @return the current {@link BaseIntegrationFlowDefinition}.
 	 * @since 6.4
+	 * @deprecated since 6.5 in favor of {@link #controlBus(Consumer)}
 	 * @see GenericEndpointSpec
 	 * @see ControlBusMessageProcessor
 	 */
+	@Deprecated(since = "6.5", forRemoval = true)
 	public B controlBusOnRegistry(@Nullable Consumer<GenericEndpointSpec<ServiceActivatingHandler>> endpointConfigurer) {
-		return handle(new ServiceActivatingHandler(new ControlBusMessageProcessor()), endpointConfigurer);
+		return controlBus(endpointConfigurer);
 	}
 
 	/**
 	 * Populate the {@code Control Bus} EI Pattern specific {@link MessageHandler} implementation
 	 * at the current {@link IntegrationFlow} chain position.
 	 * @return the current {@link BaseIntegrationFlowDefinition}.
-	 * @deprecated in favor of {@link #controlBusOnRegistry()} - will be restored in next version.
 	 */
-	@Deprecated(since = "6.4")
 	public B controlBus() {
 		return controlBus(null);
 	}
@@ -553,15 +555,10 @@ public B controlBus() {
 	 * at the current {@link IntegrationFlow} chain position.
 	 * @param endpointConfigurer the {@link Consumer} to accept integration endpoint options.
 	 * @return the current {@link BaseIntegrationFlowDefinition}.
-	 * @deprecated in favor of {@link #controlBusOnRegistry(Consumer)} - will be restored in next version.
 	 * @see GenericEndpointSpec
 	 */
-	@Deprecated(since = "6.4")
-	@SuppressWarnings("removal")
 	public B controlBus(@Nullable Consumer<GenericEndpointSpec<ServiceActivatingHandler>> endpointConfigurer) {
-		return handle(new ServiceActivatingHandler(
-				new org.springframework.integration.handler.ExpressionCommandMessageProcessor(
-						new org.springframework.integration.expression.ControlBusMethodFilter())), endpointConfigurer);
+		return handle(new ServiceActivatingHandler(new ControlBusMessageProcessor()), endpointConfigurer);
 	}
 
 	/**

spring-integration-core/src/main/java/org/springframework/integration/dsl/BaseIntegrationFlowDefinition.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2020-2024 the original author or authors.
+ * Copyright 2020-2025 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.
@@ -285,17 +285,15 @@ class KotlinIntegrationFlowDefinition(@PublishedApi internal val delegate: Integ
 	 * at the current [IntegrationFlow] chain position.
 	 * @since 6.4
 	 */
+	@Deprecated("Use 'controlBus()' instead.", replaceWith = ReplaceWith("controlBus()"))
 	fun controlBusOnRegistry(endpointConfigurer: GenericEndpointSpec<ServiceActivatingHandler>.() -> Unit = {}) {
-		this.delegate.controlBusOnRegistry(endpointConfigurer)
+		controlBus(endpointConfigurer)
 	}
 
 	/**
 	 * Populate the `Control Bus` EI Pattern specific [MessageHandler] implementation
 	 * at the current [IntegrationFlow] chain position.
 	 */
-	@Deprecated("Use 'controlBusOnRegistry()' instead.",
-		replaceWith = ReplaceWith("controlBusOnRegistry()"))
-	@Suppress("DEPRECATION", "REMOVAL")
 	fun controlBus(endpointConfigurer: GenericEndpointSpec<ServiceActivatingHandler>.() -> Unit = {}) {
 		this.delegate.controlBus(endpointConfigurer)
 	}

spring-integration-core/src/main/java/org/springframework/integration/handler/ExpressionCommandMessageProcessor.java

@@ -4978,13 +4978,12 @@ The list of component name patterns you want to track (e.g.,  tracked-components
 			]]></xsd:documentation>
 		</xsd:annotation>
 		<xsd:attribute name="id" type="xsd:string"/>
-		<xsd:attribute name="use-registry" type="xsd:boolean" default="false">
+		<xsd:attribute name="use-registry" type="xsd:boolean">
 			<xsd:annotation>
 				<xsd:documentation>
-					Set true to make Control Bus based on the global 'ControlBusCommandRegistry'
-					which is a recommended way to configure Control Bus functionality.
-					The false is by default for backward compatibility and is deprecated.
-					This attribute will be true by default in the next major version and removed altogether eventually.
+					[DEPRECATED]
+					The attribute is out of use since 6.5 and 'ControlBusCommandRegistry' is always configured.
+					Will be removed in the next version.
 				</xsd:documentation>
 			</xsd:annotation>
 		</xsd:attribute>

spring-integration-core/src/main/kotlin/org/springframework/integration/dsl/KotlinIntegrationFlowDefinition.kt

@@ -20,6 +20,6 @@
 	<beans:bean id="aggregatorBean"
 		class="org.springframework.integration.config.TestAggregatorBean" />
 
-	<control-bus input-channel="controlBusChannel" output-channel="nullChannel" use-registry="true"/>
+	<control-bus input-channel="controlBusChannel" output-channel="nullChannel"/>
 
 </beans:beans>

spring-integration-core/src/main/resources/org/springframework/integration/config/spring-integration.xsd

@@ -1,7 +1,8 @@
 <?xml version="1.0" encoding="UTF-8"?>
-<beans:beans xmlns="http://www.springframework.org/schema/integration" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
-	xmlns:beans="http://www.springframework.org/schema/beans" xmlns:groovy="http://www.springframework.org/schema/integration/groovy"
-	xsi:schemaLocation="http://www.springframework.org/schema/integration
+<beans:beans xmlns="http://www.springframework.org/schema/integration"
+			 xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+			 xmlns:beans="http://www.springframework.org/schema/beans"
+			 xsi:schemaLocation="http://www.springframework.org/schema/integration
 		https://www.springframework.org/schema/integration/spring-integration.xsd
 		http://www.springframework.org/schema/beans
 		https://www.springframework.org/schema/beans/spring-beans.xsd">
@@ -14,6 +15,6 @@
 		<control-bus/>
 	</chain>
 
-	<beans:bean id="service" class="org.springframework.integration.config.xml.ControlBusChainTests$Service" />
+	<beans:bean id="service" class="org.springframework.integration.config.xml.ControlBusChainTests$Service"/>
 
 </beans:beans>