Polish Optional usage

Author: ngocnhan-tran1996

oauth2/oauth2-client/src/main/java/org/springframework/security/oauth2/client/web/reactive/function/client/ServletOAuth2AuthorizedClientExchangeFilterFunction.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2022 the original author or authors.
+ * Copyright 2002-2024 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.
@@ -395,9 +395,9 @@ private Mono<ClientResponse> exchangeAndHandleResponse(ClientRequest request, Ex
 	}
 
 	private Mono<ClientRequest> mergeRequestAttributesIfNecessary(ClientRequest request) {
-		if (!request.attribute(HTTP_SERVLET_REQUEST_ATTR_NAME).isPresent()
-				|| !request.attribute(HTTP_SERVLET_RESPONSE_ATTR_NAME).isPresent()
-				|| !request.attribute(AUTHENTICATION_ATTR_NAME).isPresent()) {
+		if (request.attribute(HTTP_SERVLET_REQUEST_ATTR_NAME).isEmpty()
+				|| request.attribute(HTTP_SERVLET_RESPONSE_ATTR_NAME).isEmpty()
+				|| request.attribute(AUTHENTICATION_ATTR_NAME).isEmpty()) {
 			return mergeRequestAttributesFromContext(request);
 		}
 		return Mono.just(request);

web/src/main/java/org/springframework/security/web/server/authentication/SwitchUserWebFilter.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2022 the original author or authors.
+ * Copyright 2002-2024 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.
@@ -228,7 +228,7 @@ private Mono<Authentication> attemptSwitchUser(Authentication currentAuthenticat
 	@NonNull
 	private Authentication attemptExitUser(Authentication currentAuthentication) {
 		Optional<Authentication> sourceAuthentication = extractSourceAuthentication(currentAuthentication);
-		if (!sourceAuthentication.isPresent()) {
+		if (sourceAuthentication.isEmpty()) {
 			this.logger.debug("Failed to find original user");
 			throw noOriginalAuthenticationException();
 		}