Merge pull request #32144 from russellyou

* pr/32144:
  Polish "Allow Netty default leak detection to be overidden"
  Allow Netty default leak detection to be overidden

Closes gh-32144

spring-boot-project/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/netty/NettyProperties.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2021 the original author or authors.
+ * Copyright 2012-2022 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -30,9 +30,11 @@ import org.springframework.boot.context.properties.ConfigurationProperties;
 public class NettyProperties {
 
 	/**
-	 * Level of leak detection for reference-counted buffers.
+	 * Level of leak detection for reference-counted buffers. If not configured via
+	 * 'ResourceLeakDetector.setLevel' or the 'io.netty.leakDetection.level' system
+	 * property, default to 'simple'.
 	 */
-	private LeakDetection leakDetection = LeakDetection.SIMPLE;
+	private LeakDetection leakDetection;
 
 	public LeakDetection getLeakDetection() {
 		return this.leakDetection;

spring-boot-project/spring-boot-autoconfigure/src/main/resources/META-INF/additional-spring-configuration-metadata.json

@@ -1736,10 +1736,6 @@
       "name": "spring.neo4j.uri",
       "defaultValue": "bolt://localhost:7687"
     },
-    {
-      "name": "spring.netty.leak-detection",
-      "defaultValue": "simple"
-    },
     {
       "name": "spring.quartz.jdbc.comment-prefix",
       "defaultValue": [

spring-boot-project/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/netty/NettyPropertiesTests.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2021 the original author or authors.
+ * Copyright 2012-2022 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -32,11 +32,10 @@ import static org.assertj.core.api.Assertions.assertThat;
 class NettyPropertiesTests {
 
 	@Test
-	void defaultValueShouldMatchNettys() {
-		NettyProperties properties = new NettyProperties();
+	void defaultValueShouldBeConsistent() {
 		ResourceLeakDetector.Level defaultLevel = (Level) ReflectionTestUtils.getField(ResourceLeakDetector.class,
 				"DEFAULT_LEVEL");
-		assertThat(ResourceLeakDetector.Level.valueOf(properties.getLeakDetection().name())).isEqualTo(defaultLevel);
+		assertThat(defaultLevel).isEqualTo(Level.SIMPLE);
 	}
 
 }