java.util.concurrent.CompletionException: java.lang.NullPointerException
	at org.infinispan.util.concurrent.CompletionStages.join(CompletionStages.java:81)
	at org.infinispan.persistence.support.AsyncStoreTest.tearDown(AsyncStoreTest.java:87)
	at java.util.concurrent.FutureTask.run(FutureTask.java:266)
	at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
	at java.lang.Thread.run(Thread.java:748)
Caused by: java.lang.NullPointerException
	at org.infinispan.persistence.async.AsyncNonBlockingStore.lambda$retry$9(AsyncNonBlockingStore.java:275)
	at java.util.concurrent.CompletableFuture.uniHandle(CompletableFuture.java:836)
	at java.util.concurrent.CompletableFuture.uniHandleStage(CompletableFuture.java:848)
	at java.util.concurrent.CompletableFuture.handle(CompletableFuture.java:2168)
	at java.util.concurrent.CompletableFuture.handle(CompletableFuture.java:110)
	at org.infinispan.util.concurrent.CompletionStages.handleAndCompose(CompletionStages.java:140)
	at org.infinispan.persistence.async.AsyncNonBlockingStore.retry(AsyncNonBlockingStore.java:268)
	at org.infinispan.persistence.async.AsyncNonBlockingStore.lambda$submitTask$5(AsyncNonBlockingStore.java:222)
	at java.util.concurrent.CompletableFuture.uniComposeStage(CompletableFuture.java:995)
	at java.util.concurrent.CompletableFuture.thenCompose(CompletableFuture.java:2137)
	at java.util.concurrent.CompletableFuture.thenCompose(CompletableFuture.java:110)
	at org.infinispan.persistence.async.AsyncNonBlockingStore.submitTask(AsyncNonBlockingStore.java:217)
	at org.infinispan.persistence.async.AsyncNonBlockingStore.submitModification(AsyncNonBlockingStore.java:494)
	at org.infinispan.persistence.async.AsyncNonBlockingStore.write(AsyncNonBlockingStore.java:506)
	at org.infinispan.persistence.support.AsyncStoreTest.lambda$testModificationQueueSize$1(AsyncStoreTest.java:348)
	at org.infinispan.test.AbstractInfinispanTest$CallableWrapper.call(AbstractInfinispanTest.java:527)
	... 4 more
... Removed 19 stack frames