Polish spring-security-rsocket main code

Manually polish `spring-security-rsocket` following the formatting
and checkstyle fixes.

Issue gh-8945

rsocket/src/main/java/org/springframework/security/rsocket/authentication/AnonymousPayloadInterceptor.java

@@ -39,11 +39,11 @@ import org.springframework.util.Assert;
  */
 public class AnonymousPayloadInterceptor implements PayloadInterceptor, Ordered {
 
-	private String key;
+	private final String key;
 
-	private Object principal;
+	private final Object principal;
 
-	private List<GrantedAuthority> authorities;
+	private final List<GrantedAuthority> authorities;
 
 	private int order;
 

rsocket/src/main/java/org/springframework/security/rsocket/authentication/AuthenticationPayloadExchangeConverter.java

@@ -56,7 +56,7 @@ public class AuthenticationPayloadExchangeConverter implements PayloadExchangeAu
 	private static final MimeType AUTHENTICATION_MIME_TYPE = MimeTypeUtils
 			.parseMimeType(WellKnownMimeType.MESSAGE_RSOCKET_AUTHENTICATION.getString());
 
-	private MetadataExtractor metadataExtractor = createDefaultExtractor();
+	private final MetadataExtractor metadataExtractor = createDefaultExtractor();
 
 	@Override
 	public Mono<Authentication> convert(PayloadExchange exchange) {
@@ -79,7 +79,7 @@ public class AuthenticationPayloadExchangeConverter implements PayloadExchangeAu
 		if (WellKnownAuthType.SIMPLE.equals(wellKnownAuthType)) {
 			return simple(rawAuthentication);
 		}
-		else if (WellKnownAuthType.BEARER.equals(wellKnownAuthType)) {
+		if (WellKnownAuthType.BEARER.equals(wellKnownAuthType)) {
 			return bearer(rawAuthentication);
 		}
 		throw new IllegalArgumentException("Unknown Mime Type " + wellKnownAuthType);

rsocket/src/main/java/org/springframework/security/rsocket/authorization/PayloadExchangeMatcherReactiveAuthorizationManager.java

@@ -28,6 +28,7 @@ import org.springframework.security.core.Authentication;
 import org.springframework.security.rsocket.api.PayloadExchange;
 import org.springframework.security.rsocket.util.matcher.PayloadExchangeAuthorizationContext;
 import org.springframework.security.rsocket.util.matcher.PayloadExchangeMatcher;
+import org.springframework.security.rsocket.util.matcher.PayloadExchangeMatcher.MatchResult;
 import org.springframework.security.rsocket.util.matcher.PayloadExchangeMatcherEntry;
 import org.springframework.util.Assert;
 
@@ -53,7 +54,7 @@ public final class PayloadExchangeMatcherReactiveAuthorizationManager
 	public Mono<AuthorizationDecision> check(Mono<Authentication> authentication, PayloadExchange exchange) {
 		return Flux.fromIterable(this.mappings)
 				.concatMap((mapping) -> mapping.getMatcher().matches(exchange)
-						.filter(PayloadExchangeMatcher.MatchResult::isMatch).map((r) -> r.getVariables())
+						.filter(PayloadExchangeMatcher.MatchResult::isMatch).map(MatchResult::getVariables)
 						.flatMap((variables) -> mapping.getEntry().check(authentication,
 								new PayloadExchangeAuthorizationContext(exchange, variables))))
 				.next().switchIfEmpty(Mono.fromCallable(() -> new AuthorizationDecision(false)));

rsocket/src/main/java/org/springframework/security/rsocket/core/PayloadSocketAcceptor.java

@@ -66,10 +66,8 @@ class PayloadSocketAcceptor implements SocketAcceptor {
 	public Mono<RSocket> accept(ConnectionSetupPayload setup, RSocket sendingSocket) {
 		MimeType dataMimeType = parseMimeType(setup.dataMimeType(), this.defaultDataMimeType);
 		Assert.notNull(dataMimeType, "No `dataMimeType` in ConnectionSetupPayload and no default value");
-
 		MimeType metadataMimeType = parseMimeType(setup.metadataMimeType(), this.defaultMetadataMimeType);
 		Assert.notNull(metadataMimeType, "No `metadataMimeType` in ConnectionSetupPayload and no default value");
-
 		// FIXME do we want to make the sendingSocket available in the PayloadExchange
 		return intercept(setup, dataMimeType, metadataMimeType)
 				.flatMap(

rsocket/src/main/java/org/springframework/security/rsocket/metadata/BasicAuthenticationDecoder.java

@@ -48,7 +48,6 @@ public class BasicAuthenticationDecoder extends AbstractDecoder<UsernamePassword
 		return Flux.from(input).map(DataBuffer::asByteBuffer).map((byteBuffer) -> {
 			byte[] sizeBytes = new byte[4];
 			byteBuffer.get(sizeBytes);
-
 			int usernameSize = 4;
 			byte[] usernameBytes = new byte[usernameSize];
 			byteBuffer.get(usernameBytes);

rsocket/src/main/java/org/springframework/security/rsocket/util/matcher/PayloadExchangeMatchers.java

@@ -24,37 +24,43 @@ import org.springframework.security.rsocket.api.PayloadExchangeType;
 /**
  * @author Rob Winch
  */
-public abstract class PayloadExchangeMatchers {
+public final class PayloadExchangeMatchers {
+
+	private PayloadExchangeMatchers() {
+	}
 
 	public static PayloadExchangeMatcher setup() {
 		return new PayloadExchangeMatcher() {
+
 			@Override
 			public Mono<MatchResult> matches(PayloadExchange exchange) {
 				return PayloadExchangeType.SETUP.equals(exchange.getType()) ? MatchResult.match()
 						: MatchResult.notMatch();
 			}
+
 		};
 	}
 
 	public static PayloadExchangeMatcher anyRequest() {
 		return new PayloadExchangeMatcher() {
+
 			@Override
 			public Mono<MatchResult> matches(PayloadExchange exchange) {
 				return exchange.getType().isRequest() ? MatchResult.match() : MatchResult.notMatch();
 			}
+
 		};
 	}
 
 	public static PayloadExchangeMatcher anyExchange() {
 		return new PayloadExchangeMatcher() {
+
 			@Override
 			public Mono<MatchResult> matches(PayloadExchange exchange) {
 				return MatchResult.match();
 			}
+
 		};
 	}
 
-	private PayloadExchangeMatchers() {
-	}
-
 }

rsocket/src/main/java/org/springframework/security/rsocket/util/matcher/RoutePayloadExchangeMatcher.java

@@ -26,10 +26,9 @@ import org.springframework.security.rsocket.api.PayloadExchange;
 import org.springframework.util.Assert;
 import org.springframework.util.RouteMatcher;
 
+// FIXME: Pay attention to the package this goes into. It requires spring-messaging for the MetadataExtractor.
+
 /**
- * FIXME: Pay attention to the package this goes into. It requires spring-messaging for
- * the MetadataExtractor.
- *
  * @author Rob Winch
  * @since 5.2
  */