GH-85: Add SqsMDChannelAdapter.getQueue()

Fixes spring-projects/spring-integration-aws#85

* For better component management add
`SqsMessageDrivenChannelAdapter.getQueue()` to return what queues this
channel adapter is subscribed
* Upgrade to Gradle 4.6 and Checkstyle 8.8

build.gradle

@@ -91,7 +91,7 @@ jacoco {
 
 checkstyle {
 	configFile = file("${rootDir}/src/checkstyle/checkstyle.xml")
-	toolVersion = "8.5"
+	toolVersion = "8.8"
 }
 
 dependencies {

gradle/wrapper/gradle-wrapper.properties

@@ -1,5 +1,5 @@
 distributionBase=GRADLE_USER_HOME
 distributionPath=wrapper/dists
+distributionUrl=https\://services.gradle.org/distributions/gradle-4.6-bin.zip
 zipStoreBase=GRADLE_USER_HOME
 zipStorePath=wrapper/dists
-distributionUrl=https\://services.gradle.org/distributions/gradle-4.4.1-bin.zip

src/main/java/org/springframework/integration/aws/inbound/SqsMessageDrivenChannelAdapter.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2016-2017 the original author or authors.
+ * Copyright 2016-2018 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.
@@ -33,6 +33,7 @@ import org.springframework.core.task.AsyncTaskExecutor;
 import org.springframework.integration.aws.support.AwsHeaders;
 import org.springframework.integration.endpoint.MessageProducerSupport;
 import org.springframework.integration.support.management.IntegrationManagedResource;
+import org.springframework.jmx.export.annotation.ManagedAttribute;
 import org.springframework.jmx.export.annotation.ManagedOperation;
 import org.springframework.jmx.export.annotation.ManagedResource;
 import org.springframework.messaging.Message;
@@ -160,6 +161,11 @@ public class SqsMessageDrivenChannelAdapter extends MessageProducerSupport imple
 		return this.listenerContainer.isRunning(logicalQueueName);
 	}
 
+	@ManagedAttribute
+	public String[] getQueues() {
+		return  Arrays.copyOf(this.queues, this.queues.length);
+	}
+
 	@Override
 	public void destroy() {
 		this.listenerContainer.destroy();

src/test/java/org/springframework/integration/aws/inbound/SqsMessageDrivenChannelAdapterTests.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2015-2017 the original author or authors.
+ * Copyright 2015-2018 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.
@@ -108,6 +108,8 @@ public class SqsMessageDrivenChannelAdapterTests {
 				this.controlBusInput.send(new GenericMessage<>("@sqsMessageDrivenChannelAdapter.start('foo')")))
 				.hasCauseExactlyInstanceOf(IllegalArgumentException.class)
 				.hasMessageContaining("Queue with name 'foo' does not exist");
+
+		assertThat(this.sqsMessageDrivenChannelAdapter.getQueues()).isEqualTo(new String[] { "testQueue" });
 	}
 
 	@Configuration