GH-4007: Remove MQTT ConsumerStopAction

Fixes #4007

It was deprecated in the previous version and fully covered with existing `cleanSession` connection option.

Author: artembilan

spring-integration-mqtt/src/main/java/org/springframework/integration/mqtt/core/ConsumerStopAction.java

@@ -41,9 +41,6 @@ public class DefaultMqttPahoClientFactory implements MqttPahoClientFactory {
 
 	private MqttClientPersistence persistence;
 
-	@SuppressWarnings("deprecation")
-	private ConsumerStopAction consumerStopAction = ConsumerStopAction.UNSUBSCRIBE_CLEAN;
-
 	/**
 	 * Set the persistence to pass into the client constructor.
 	 * @param persistence the persistence to set.
@@ -52,32 +49,6 @@ public void setPersistence(MqttClientPersistence persistence) {
 		this.persistence = persistence;
 	}
 
-	/**
-	 * Get the consumer stop action.
-	 * @return the consumer stop action.
-	 * @since 4.2.3
-	 * @deprecated since 5.5.17 in favor of standard {@link MqttConnectOptions#setCleanSession(boolean)}.
-	 * Will be removed in 6.1.0.
-	 */
-	@Deprecated
-	@Override
-	public ConsumerStopAction getConsumerStopAction() {
-		return this.consumerStopAction;
-	}
-
-	/**
-	 * Set the consumer stop action. Determines whether we unsubscribe when the consumer stops.
-	 * Default: {@link ConsumerStopAction#UNSUBSCRIBE_CLEAN}.
-	 * @param consumerStopAction the consumer stop action.
-	 * @since 4.2.3.
-	 * @deprecated since 5.5.17 in favor of standard {@link MqttConnectOptions#setCleanSession(boolean)}.
-	 * Will be removed in 6.1.0.
-	 */
-	@Deprecated
-	public void setConsumerStopAction(ConsumerStopAction consumerStopAction) {
-		this.consumerStopAction = consumerStopAction;
-	}
-
 	@Override
 	public IMqttClient getClientInstance(String uri, String clientId) throws MqttException {
 		// Client validates URI even if overridden by options

spring-integration-mqtt/src/main/java/org/springframework/integration/mqtt/core/DefaultMqttPahoClientFactory.java

@@ -56,14 +56,4 @@ public interface MqttPahoClientFactory {
 	 */
 	MqttConnectOptions getConnectionOptions();
 
-	/**
-	 * Get the consumer stop action.
-	 * @return the consumer stop action.
-	 * @since 4.3
-	 * @deprecated since 5.5.17 in favor of standard {@link MqttConnectOptions#setCleanSession(boolean)}.
-	 * Will be removed in 6.1.0.
-	 */
-	@Deprecated
-	ConsumerStopAction getConsumerStopAction();
-
 }

spring-integration-mqtt/src/main/java/org/springframework/integration/mqtt/core/MqttPahoClientFactory.java

@@ -68,9 +68,6 @@ public class MqttPahoMessageDrivenChannelAdapter
 
 	private volatile IMqttAsyncClient client;
 
-	@SuppressWarnings("deprecation")
-	private volatile org.springframework.integration.mqtt.core.ConsumerStopAction consumerStopAction;
-
 	private volatile boolean readyToSubscribeOnStart;
 
 	/**
@@ -184,11 +181,6 @@ protected void doStart() {
 	@SuppressWarnings("deprecation")
 	private synchronized void connect() throws MqttException {
 		MqttConnectOptions connectionOptions = this.clientFactory.getConnectionOptions();
-		this.consumerStopAction = this.clientFactory.getConsumerStopAction();
-		if (this.consumerStopAction == null) {
-			this.consumerStopAction = org.springframework.integration.mqtt.core.ConsumerStopAction.UNSUBSCRIBE_CLEAN;
-		}
-
 		var clientManager = getClientManager();
 		if (clientManager == null) {
 			Assert.state(getUrl() != null || connectionOptions.getServerURIs() != null,
@@ -203,17 +195,11 @@ private synchronized void connect() throws MqttException {
 		}
 	}
 
-	@SuppressWarnings("deprecation")
 	@Override
 	protected synchronized void doStop() {
 		this.readyToSubscribeOnStart = false;
 		try {
-			if (this.consumerStopAction
-					.equals(org.springframework.integration.mqtt.core.ConsumerStopAction.UNSUBSCRIBE_ALWAYS)
-					|| (this.consumerStopAction
-					.equals(org.springframework.integration.mqtt.core.ConsumerStopAction.UNSUBSCRIBE_CLEAN)
-					&& this.clientFactory.getConnectionOptions().isCleanSession())) {
-
+			if (this.clientFactory.getConnectionOptions().isCleanSession()) {
 				this.client.unsubscribe(getTopic());
 				// Have to re-subscribe on next start if connection is not lost.
 				this.readyToSubscribeOnStart = true;