remove AlreadyAcknowledgedException, return void instead of ChangeMes…

…sageVisibilityResult

src/main/java/com/mercateo/sqs/utils/message/handling/MessageWrapper.java

@@ -2,7 +2,6 @@
 
 import com.amazonaws.services.sqs.AmazonSQS;
 import com.amazonaws.services.sqs.model.ChangeMessageVisibilityRequest;
-import com.amazonaws.services.sqs.model.ChangeMessageVisibilityResult;
 
 import io.awspring.cloud.messaging.listener.Acknowledgment;
 
@@ -43,10 +42,10 @@ public synchronized void acknowledge() {
         acknowledged.set(true);
     }
 
-    public synchronized ChangeMessageVisibilityResult changeMessageVisibility(AmazonSQS sqsClient, ChangeMessageVisibilityRequest request) {
+    public synchronized void changeMessageVisibility(AmazonSQS sqsClient, ChangeMessageVisibilityRequest request) {
         if (acknowledged.get()) {
-            throw new AlreadyAcknowledgedException();
+            return;
         }
-        return sqsClient.changeMessageVisibility(request);
+        sqsClient.changeMessageVisibility(request);
     }
 }

src/main/java/com/mercateo/sqs/utils/visibility/VisibilityTimeoutExtender.java

@@ -1,12 +1,12 @@
 /**
  * Copyright © 2017 Mercateo AG (http://www.mercateo.com)
- *
+ * <p>
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
- *
- *     http://www.apache.org/licenses/LICENSE-2.0
- *
+ * <p>
+ * http://www.apache.org/licenses/LICENSE-2.0
+ * <p>
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
@@ -18,10 +18,8 @@
 import com.amazonaws.AmazonServiceException;
 import com.amazonaws.services.sqs.AmazonSQS;
 import com.amazonaws.services.sqs.model.ChangeMessageVisibilityRequest;
-import com.amazonaws.services.sqs.model.ChangeMessageVisibilityResult;
 import com.github.rholder.retry.Retryer;
 import com.github.rholder.retry.RetryerBuilder;
-import com.mercateo.sqs.utils.message.handling.AlreadyAcknowledgedException;
 import com.mercateo.sqs.utils.message.handling.ErrorHandlingStrategy;
 import com.mercateo.sqs.utils.message.handling.MessageWrapper;
 
@@ -42,7 +40,7 @@ public class VisibilityTimeoutExtender implements Runnable {
 
     private final ErrorHandlingStrategy<?> errorHandlingStrategy;
 
-    private final Retryer<ChangeMessageVisibilityResult> retryer;
+    private final Retryer<Void> retryer;
 
     VisibilityTimeoutExtender(@NonNull AmazonSQS sqsClient, @NonNull Duration newVisibilityTimeout,
                               @NonNull MessageWrapper<?> messageWrapper, @NonNull String queueUrl,
@@ -52,15 +50,15 @@ public class VisibilityTimeoutExtender implements Runnable {
         this.messageWrapper = messageWrapper;
         this.errorHandlingStrategy = errorHandlingStrategy;
         this.retryer = RetryerBuilder
-                .<ChangeMessageVisibilityResult> newBuilder()
+                .<Void>newBuilder()
                 .retryIfException(t -> (t.getCause() instanceof UnknownHostException))
                 .withWaitStrategy(retryStrategy.getRetryWaitStrategy())
                 .withStopStrategy(retryStrategy.getRetryStopStrategy())
                 .build();
 
         request = new ChangeMessageVisibilityRequest().withQueueUrl(queueUrl).withReceiptHandle(
                 messageWrapper.getReceiptHandle()).withVisibilityTimeout(
-                        timeoutInSeconds(newVisibilityTimeout));
+                timeoutInSeconds(newVisibilityTimeout));
     }
 
     private Integer timeoutInSeconds(Duration timeout) {
@@ -70,11 +68,11 @@ private Integer timeoutInSeconds(Duration timeout) {
     @Override
     public void run() {
         try {
-            retryer.call(() -> messageWrapper.changeMessageVisibility(sqsClient, request));
+            retryer.call(() -> {
+                messageWrapper.changeMessageVisibility(sqsClient, request);
+                return null;
+            });
         } catch (Exception e) {
-            if (e.getCause() instanceof AlreadyAcknowledgedException) {
-                return;
-            }
             if (e.getCause() instanceof AmazonServiceException) {
                 errorHandlingStrategy.handleExtendVisibilityTimeoutException((AmazonServiceException) e.getCause(), messageWrapper.getMessage());
             } else {