From ae1aaad67a5d86715c3288e6ecb690c1552862f7 Mon Sep 17 00:00:00 2001
From: Zahid Khan <63726443+ZFK07@users.noreply.github.com>
Date: Wed, 6 Jul 2022 23:48:34 +0530
Subject: [PATCH] Check for null before setting maxSubscribers

The `DirectChannel` doesn't check a result of the `getIntegrationProperty()`.
This may cause NPE problem with unconditional `setMaxSubscribers(int)` call.

* Check `Integer max` for `null` before propagating to the `setMaxSubscribers()`
---
 .../springframework/integration/channel/DirectChannel.java    | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/spring-integration-core/src/main/java/org/springframework/integration/channel/DirectChannel.java b/spring-integration-core/src/main/java/org/springframework/integration/channel/DirectChannel.java
index 524e7db0c7..1e624852bf 100644
--- a/spring-integration-core/src/main/java/org/springframework/integration/channel/DirectChannel.java
+++ b/spring-integration-core/src/main/java/org/springframework/integration/channel/DirectChannel.java
@@ -87,7 +87,9 @@ public class DirectChannel extends AbstractSubscribableChannel {
 		super.onInit();
 		if (this.maxSubscribers == null) {
 			Integer max = getIntegrationProperty(IntegrationProperties.CHANNELS_MAX_UNICAST_SUBSCRIBERS, Integer.class);
-			setMaxSubscribers(max);
+			if (max != null) {
+				setMaxSubscribers(max);
+			}
 		}
 	}