From bcfd8efe66c4429ac8eabf82f87309019760234c Mon Sep 17 00:00:00 2001
From: Raymond Xu <2701446+xushiyan@users.noreply.github.com>
Date: Mon, 14 Feb 2022 11:06:31 -0800
Subject: [PATCH] [MINOR] Prevent async service from starting twice (#4801)

---
 .../main/java/org/apache/hudi/async/HoodieAsyncService.java   | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/hudi-client/hudi-client-common/src/main/java/org/apache/hudi/async/HoodieAsyncService.java b/hudi-client/hudi-client-common/src/main/java/org/apache/hudi/async/HoodieAsyncService.java
index f57484d88..9f41080d2 100644
--- a/hudi-client/hudi-client-common/src/main/java/org/apache/hudi/async/HoodieAsyncService.java
+++ b/hudi-client/hudi-client-common/src/main/java/org/apache/hudi/async/HoodieAsyncService.java
@@ -125,6 +125,10 @@ public abstract class HoodieAsyncService implements Serializable {
    * @param onShutdownCallback
    */
   public void start(Function<Boolean, Boolean> onShutdownCallback) {
+    if (started) {
+      LOG.warn("The async service already started.");
+      return;
+    }
     Pair<CompletableFuture, ExecutorService> res = startService();
     future = res.getKey();
     executor = res.getValue();