AsyncTemplate: Fix Sonar Violation

Accessed `beanName` directly from a synchronized method.

Also add `toString()`.

spring-rabbit/src/main/java/org/springframework/amqp/rabbit/core/AsyncRabbitTemplate.java

@@ -233,7 +233,7 @@ public class AsyncRabbitTemplate implements SmartLifecycle, MessageListener, Ret
 	}
 
 	public String getBeanName() {
-		return beanName;
+		return this.beanName;
 	}
 
 	@Override
@@ -413,7 +413,7 @@ public class AsyncRabbitTemplate implements SmartLifecycle, MessageListener, Ret
 		if (!this.running) {
 			if (this.taskScheduler == null) {
 				ThreadPoolTaskScheduler scheduler = new ThreadPoolTaskScheduler();
-				scheduler.setThreadNamePrefix(this.beanName == null ? "asyncTemplate-" : (this.beanName + "-"));
+				scheduler.setThreadNamePrefix(getBeanName() == null ? "asyncTemplate-" : (getBeanName() + "-"));
 				scheduler.afterPropertiesSet();
 				this.taskScheduler = scheduler;
 			}
@@ -537,6 +537,11 @@ public class AsyncRabbitTemplate implements SmartLifecycle, MessageListener, Ret
 		return correlationId;
 	}
 
+	@Override
+	public String toString() {
+		return this.beanName == null ? super.toString() : (this.getClass().getSimpleName() + ": " + this.beanName);
+	}
+
 	/**
 	 * Base class for {@link ListenableFuture}s returned by {@link AsyncRabbitTemplate}.
 	 * @since 1.6

spring-rabbit/src/test/java/org/springframework/amqp/rabbit/core/AsyncRabbitTemplateTests.java

@@ -370,8 +370,7 @@ public class AsyncRabbitTemplateTests {
 		}
 
 		@Bean
-		public AsyncRabbitTemplate asyncTemplate(RabbitTemplate template,
-		                                         SimpleMessageListenerContainer container) {
+		public AsyncRabbitTemplate asyncTemplate(RabbitTemplate template, SimpleMessageListenerContainer container) {
 			return new AsyncRabbitTemplate(template, container);
 		}