diff --git a/spring-integration-mqtt/src/main/java/org/springframework/integration/mqtt/inbound/MqttPahoMessageDrivenChannelAdapter.java b/spring-integration-mqtt/src/main/java/org/springframework/integration/mqtt/inbound/MqttPahoMessageDrivenChannelAdapter.java
index 8512fec992..1ce1864724 100644
--- a/spring-integration-mqtt/src/main/java/org/springframework/integration/mqtt/inbound/MqttPahoMessageDrivenChannelAdapter.java
+++ b/spring-integration-mqtt/src/main/java/org/springframework/integration/mqtt/inbound/MqttPahoMessageDrivenChannelAdapter.java
@@ -57,10 +57,10 @@ public class MqttPahoMessageDrivenChannelAdapter extends AbstractMqttMessageDriv
 
 	private final MqttPahoClientFactory clientFactory;
 
-	private long completionTimeout = DEFAULT_COMPLETION_TIMEOUT;
-
 	private int recoveryInterval = DEFAULT_RECOVERY_INTERVAL;
 
+	private volatile long completionTimeout = DEFAULT_COMPLETION_TIMEOUT;
+
 	private volatile IMqttClient client;
 
 	private volatile ScheduledFuture<?> reconnectFuture;
diff --git a/spring-integration-rmi/src/main/java/org/springframework/integration/rmi/RmiInboundGateway.java b/spring-integration-rmi/src/main/java/org/springframework/integration/rmi/RmiInboundGateway.java
index 460a7ee612..b23dca37ca 100644
--- a/spring-integration-rmi/src/main/java/org/springframework/integration/rmi/RmiInboundGateway.java
+++ b/spring-integration-rmi/src/main/java/org/springframework/integration/rmi/RmiInboundGateway.java
@@ -22,6 +22,7 @@ import org.springframework.beans.factory.InitializingBean;
 import org.springframework.integration.gateway.MessagingGatewaySupport;
 import org.springframework.integration.gateway.RequestReplyExchanger;
 import org.springframework.integration.support.context.NamedComponent;
+import org.springframework.lang.Nullable;
 import org.springframework.messaging.Message;
 import org.springframework.messaging.MessageChannel;
 import org.springframework.remoting.rmi.RmiServiceExporter;
@@ -118,6 +119,7 @@ public class RmiInboundGateway extends MessagingGatewaySupport
 	}
 
 	@Override
+	@Nullable
 	public Message<?> exchange(Message<?> message) {
 		if (this.expectReply) {
 			return sendAndReceiveMessage(message);