ARTEMIS-3928 Fixing intermittent failure after executor's change

tests/integration-tests/src/test/java/org/apache/activemq/artemis/tests/integration/paging/PagingSendTest.java

@@ -235,13 +235,25 @@ public class PagingSendTest extends ActiveMQTestBase {
       // Give time Queue.deliverAsync to deliver messages
       Assert.assertTrue("Messages were not propagated to internal structures.", waitForMessages(queue, batchSize, 3000));
 
-      checkBatchMessagesAreNotPagedTwice(queue);
+      AtomicInteger errors = new AtomicInteger(0);
+      CountDownLatch done = new CountDownLatch(1);
 
-      for (int i = 0; i < 10; i++) {
-         // execute the same count a couple times. This is to make sure the iterators have no impact regardless
-         // the number of times they are called
-         assertEquals(batchSize, processCountThroughIterator(queue));
-      }
+      queue.getPagingStore().getExecutor().execute(() -> {
+         try {
+            checkBatchMessagesAreNotPagedTwice(queue);
+            for (int i = 0; i < 10; i++) {
+               // execute the same count a couple times. This is to make sure the iterators have no impact regardless
+               // the number of times they are called
+               assertEquals(batchSize, processCountThroughIterator(queue));
+            }
+
+         } catch (Throwable e) {
+            e.printStackTrace();
+            errors.incrementAndGet();
+         }
+         done.countDown();
+      });
+      Assert.assertEquals(0, errors.get());
 
    }
 
@@ -312,6 +324,7 @@ public class PagingSendTest extends ActiveMQTestBase {
 
       Set<String> messageOrderSet = new HashSet<>();
 
+
       int duplicates = 0;
       while (pageIterator.hasNext()) {
          MessageReference reference = pageIterator.next();
@@ -320,10 +333,11 @@ public class PagingSendTest extends ActiveMQTestBase {
 
          // If add(id) returns true it means that this id was already added to this set.  Hence a duplicate is found.
          if (!messageOrderSet.add(id)) {
+            System.out.println("Received a duplicate on " + id);
             duplicates++;
          }
       }
-      assertTrue(duplicates == 0);
+      Assert.assertEquals(0, duplicates);
    }
 
    public boolean waitForMessages(Queue queue, int count, long timeout) throws Exception {