Wait for complete disposal of Reactor Netty resources

Fixes gh-23631

spring-web/src/main/java/org/springframework/http/client/reactive/ReactorResourceFactory.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2018 the original author or authors.
+ * Copyright 2002-2019 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.
@@ -181,13 +181,13 @@ public class ReactorResourceFactory implements InitializingBean, DisposableBean
 	@Override
 	public void destroy() {
 		if (this.useGlobalResources) {
-			HttpResources.disposeLoopsAndConnections();
+			HttpResources.disposeLoopsAndConnectionsLater().block();
 		}
 		else {
 			try {
 				ConnectionProvider provider = this.connectionProvider;
 				if (provider != null && this.manageConnectionProvider) {
-					provider.dispose();
+					provider.disposeLater().block();
 				}
 			}
 			catch (Throwable ex) {
@@ -197,7 +197,7 @@ public class ReactorResourceFactory implements InitializingBean, DisposableBean
 			try {
 				LoopResources resources = this.loopResources;
 				if (resources != null && this.manageLoopResources) {
-					resources.dispose();
+					resources.disposeLater().block();
 				}
 			}
 			catch (Throwable ex) {

spring-web/src/test/java/org/springframework/http/client/reactive/ReactorResourceFactoryTests.java

@@ -107,8 +107,8 @@ public class ReactorResourceFactoryTests {
 		this.resourceFactory.destroy();
 
 		// Managed (destroy disposes)..
-		verify(this.connectionProvider).dispose();
+		verify(this.connectionProvider).disposeLater();
-		verify(this.loopResources).dispose();
+		verify(this.loopResources).disposeLater();
 		verifyNoMoreInteractions(this.connectionProvider, this.loopResources);
 	}