Simplify some code

See gh-17893

spring-boot-project/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/web/reactive/ReactiveWebServerFactoryConfiguration.java

@@ -69,7 +69,7 @@ abstract class ReactiveWebServerFactoryConfiguration {
 				ObjectProvider<NettyRouteProvider> routes, ObjectProvider<NettyServerCustomizer> serverCustomizers) {
 			NettyReactiveWebServerFactory serverFactory = new NettyReactiveWebServerFactory();
 			serverFactory.setResourceFactory(resourceFactory);
-			routes.orderedStream().forEach((route) -> serverFactory.addRouteProviders(route));
+			routes.orderedStream().forEach(serverFactory::addRouteProviders);
 			serverFactory.getServerCustomizers().addAll(serverCustomizers.orderedStream().collect(Collectors.toList()));
 			return serverFactory;
 		}

spring-boot-project/spring-boot-devtools/src/main/java/org/springframework/boot/devtools/filewatch/FileSystemWatcher.java

@@ -165,9 +165,7 @@ public class FileSystemWatcher {
 	}
 
 	private void saveInitialSnapshots() {
-		for (File folder : this.folders.keySet()) {
-			this.folders.put(folder, new FolderSnapshot(folder));
-		}
+		this.folders.replaceAll((f, v) -> new FolderSnapshot(f));
 	}
 
 	/**