Add Builder to RSocketServiceProxyFactory

RSocketServiceProxyFactory now support programmatic initialization
through a builder, while bean-style initialization is deprecated.

Closes gh-29296

spring-messaging/src/main/java/org/springframework/messaging/rsocket/service/RSocketServiceProxyFactory.java

@@ -51,68 +51,85 @@ import org.springframework.util.StringValueResolver;
  */
 public final class RSocketServiceProxyFactory implements InitializingBean, EmbeddedValueResolverAware {
 
-	private final RSocketRequester rsocketRequester;
+	@Nullable
+	private final BuilderInitializedFactory builderInitializedFactory;
 
 	@Nullable
-	private List<RSocketServiceArgumentResolver> customArgumentResolvers;
-
-	@Nullable
-	private List<RSocketServiceArgumentResolver> argumentResolvers;
-
-	@Nullable
-	private StringValueResolver embeddedValueResolver;
-
-	private ReactiveAdapterRegistry reactiveAdapterRegistry = ReactiveAdapterRegistry.getSharedInstance();
-
-	private Duration blockTimeout = Duration.ofSeconds(5);
+	private final BeanStyleFactory beanStyleFactory;
 
 
 	/**
 	 * Create an instance with the underlying RSocketRequester to perform requests with.
 	 * @param rsocketRequester the requester to use
+	 * @deprecated in favor of using the Builder to initialize the
+	 * RSocketServiceProxyFactory instance.
 	 */
+	@Deprecated(since = "6.0.0-RC2", forRemoval = true)
 	public RSocketServiceProxyFactory(RSocketRequester rsocketRequester) {
-		Assert.notNull(rsocketRequester, "RSocketRequester is required");
-		this.rsocketRequester = rsocketRequester;
+		this.beanStyleFactory = new BeanStyleFactory(rsocketRequester);
+		this.builderInitializedFactory = null;
+	}
+
+	private RSocketServiceProxyFactory(
+			RSocketRequester rsocketRequester, List<RSocketServiceArgumentResolver> argumentResolvers,
+			@Nullable StringValueResolver embeddedValueResolver,
+			ReactiveAdapterRegistry reactiveAdapterRegistry, Duration blockTimeout) {
+
+		this.beanStyleFactory = null;
+		this.builderInitializedFactory = new BuilderInitializedFactory(
+				rsocketRequester, argumentResolvers, embeddedValueResolver, reactiveAdapterRegistry, blockTimeout);
 	}
 
 
 	/**
 	 * Register a custom argument resolver, invoked ahead of default resolvers.
 	 * @param resolver the resolver to add
+	 * @deprecated in favor of using the Builder to initialize the
+	 * RSocketServiceProxyFactory instance.
 	 */
+	@Deprecated(since = "6.0.0-RC2", forRemoval = true)
 	public void addCustomArgumentResolver(RSocketServiceArgumentResolver resolver) {
-		if (this.customArgumentResolvers == null) {
-			this.customArgumentResolvers = new ArrayList<>();
-		}
-		this.customArgumentResolvers.add(resolver);
+		Assert.state(this.beanStyleFactory != null, "RSocketServiceProxyFactory was created through the builder");
+		this.beanStyleFactory.addCustomArgumentResolver(resolver);
 	}
 
 	/**
 	 * Set the custom argument resolvers to use, ahead of default resolvers.
 	 * @param resolvers the resolvers to use
+	 * @deprecated in favor of using the Builder to initialize the
+	 * RSocketServiceProxyFactory instance.
 	 */
+	@Deprecated(since = "6.0.0-RC2", forRemoval = true)
 	public void setCustomArgumentResolvers(List<RSocketServiceArgumentResolver> resolvers) {
-		this.customArgumentResolvers = new ArrayList<>(resolvers);
+		Assert.state(this.beanStyleFactory != null, "RSocketServiceProxyFactory was created through the builder");
+		this.beanStyleFactory.setCustomArgumentResolvers(resolvers);
 	}
 
 	/**
 	 * Set the StringValueResolver to use for resolving placeholders and
 	 * expressions in {@link RSocketExchange#value()}.
 	 * @param resolver the resolver to use
+	 * @deprecated in favor of using the Builder to initialize the
+	 * RSocketServiceProxyFactory instance.
 	 */
+	@Deprecated(since = "6.0.0-RC2", forRemoval = true)
 	@Override
 	public void setEmbeddedValueResolver(StringValueResolver resolver) {
-		this.embeddedValueResolver = resolver;
+		Assert.state(this.beanStyleFactory != null, "RSocketServiceProxyFactory was created through the builder");
+		this.beanStyleFactory.setEmbeddedValueResolver(resolver);
 	}
 
 	/**
 	 * Set the {@link ReactiveAdapterRegistry} to use to support different
 	 * asynchronous types for RSocket service method return values.
 	 * <p>By default this is {@link ReactiveAdapterRegistry#getSharedInstance()}.
+	 * @deprecated in favor of using the Builder to initialize the
+	 * RSocketServiceProxyFactory instance.
 	 */
+	@Deprecated(since = "6.0.0-RC2", forRemoval = true)
 	public void setReactiveAdapterRegistry(ReactiveAdapterRegistry registry) {
-		this.reactiveAdapterRegistry = registry;
+		Assert.state(this.beanStyleFactory != null, "RSocketServiceProxyFactory was created through the builder");
+		this.beanStyleFactory.setReactiveAdapterRegistry(registry);
 	}
 
 	/**
@@ -120,36 +137,22 @@ public final class RSocketServiceProxyFactory implements InitializingBean, Embed
 	 * with a synchronous (blocking) method signature.
 	 * <p>By default this is 5 seconds.
 	 * @param blockTimeout the timeout value
+	 * @deprecated in favor of using the Builder to initialize the
+	 * RSocketServiceProxyFactory instance.
 	 */
+	@Deprecated(since = "6.0.0-RC2", forRemoval = true)
 	public void setBlockTimeout(Duration blockTimeout) {
-		this.blockTimeout = blockTimeout;
+		Assert.state(this.beanStyleFactory != null, "RSocketServiceProxyFactory was created through the builder");
+		this.beanStyleFactory.setBlockTimeout(blockTimeout);
 	}
 
 
 	@Override
+	@Deprecated
 	public void afterPropertiesSet() throws Exception {
-		this.argumentResolvers = initArgumentResolvers();
-	}
-
-	private List<RSocketServiceArgumentResolver> initArgumentResolvers() {
-		List<RSocketServiceArgumentResolver> resolvers = new ArrayList<>();
-
-		// Custom
-		if (this.customArgumentResolvers != null) {
-			resolvers.addAll(this.customArgumentResolvers);
+		if (this.beanStyleFactory != null) {
+			this.beanStyleFactory.afterPropertiesSet();
 		}
-
-		// Annotation-based
-		resolvers.add(new PayloadArgumentResolver(this.reactiveAdapterRegistry, false));
-		resolvers.add(new DestinationVariableArgumentResolver());
-
-		// Type-based
-		resolvers.add(new MetadataArgumentResolver());
-
-		// Fallback
-		resolvers.add(new PayloadArgumentResolver(this.reactiveAdapterRegistry, true));
-
-		return resolvers;
 	}
 
 
@@ -162,26 +165,138 @@ public final class RSocketServiceProxyFactory implements InitializingBean, Embed
 	 * @return the created proxy
 	 */
 	public <S> S createClient(Class<S> serviceType) {
-
-		List<RSocketServiceMethod> serviceMethods =
-				MethodIntrospector.selectMethods(serviceType, this::isExchangeMethod).stream()
-						.map(method -> createRSocketServiceMethod(serviceType, method))
-						.toList();
-
-		return ProxyFactory.getProxy(serviceType, new ServiceMethodInterceptor(serviceMethods));
+		if (this.builderInitializedFactory != null) {
+			return this.builderInitializedFactory.createClient(serviceType);
+		}
+		else if (this.beanStyleFactory != null) {
+			return this.beanStyleFactory.createClient(serviceType);
+		}
+		else {
+			throw new IllegalStateException("Expected Builder initialized or Bean-style delegate");
+		}
 	}
 
-	private boolean isExchangeMethod(Method method) {
-		return AnnotatedElementUtils.hasAnnotation(method, RSocketExchange.class);
+
+	/**
+	 * Return an {@link RSocketServiceProxyFactory} builder, initialized with the
+	 * given client.
+	 */
+	public static Builder builder(RSocketRequester requester) {
+		return new Builder().rsocketRequester(requester);
 	}
 
-	private <S> RSocketServiceMethod createRSocketServiceMethod(Class<S> serviceType, Method method) {
-		Assert.notNull(this.argumentResolvers,
-				"No argument resolvers: afterPropertiesSet was not called");
+	/**
+	 * Return an {@link RSocketServiceProxyFactory} builder.
+	 */
+	public static Builder builder() {
+		return new Builder();
+	}
 
-		return new RSocketServiceMethod(
-				method, serviceType, this.argumentResolvers, this.rsocketRequester,
-				this.embeddedValueResolver, this.reactiveAdapterRegistry, this.blockTimeout);
+
+	/**
+	 * Builder to create an {@link RSocketServiceProxyFactory}.
+	 */
+	public static final class Builder {
+
+		@Nullable
+		private RSocketRequester rsocketRequester;
+
+		private final List<RSocketServiceArgumentResolver> customArgumentResolvers = new ArrayList<>();
+
+		@Nullable
+		private StringValueResolver embeddedValueResolver;
+
+		private ReactiveAdapterRegistry reactiveAdapterRegistry = ReactiveAdapterRegistry.getSharedInstance();
+
+		@Nullable
+		private Duration blockTimeout = Duration.ofSeconds(5);
+
+		private Builder() {
+		}
+
+		/**
+		 * Provide the requester to perform requests through.
+		 * @param requester the requester to use
+		 * @return the same builder instance
+		 */
+		public Builder rsocketRequester(RSocketRequester requester) {
+			this.rsocketRequester = requester;
+			return this;
+		}
+
+		/**
+		 * Register a custom argument resolver, invoked ahead of default resolvers.
+		 * @param resolver the resolver to add
+		 * @return the same builder instance
+		 */
+		public Builder customArgumentResolver(RSocketServiceArgumentResolver resolver) {
+			this.customArgumentResolvers.add(resolver);
+			return this;
+		}
+
+		/**
+		 * Set the {@link StringValueResolver} to use for resolving placeholders
+		 * and expressions embedded in {@link RSocketExchange#value()}.
+		 * @param resolver the resolver to use
+		 * @return this same builder instance
+		 */
+		public Builder embeddedValueResolver(StringValueResolver resolver) {
+			this.embeddedValueResolver = resolver;
+			return this;
+		}
+
+		/**
+		 * Set the {@link ReactiveAdapterRegistry} to use to support different
+		 * asynchronous types for HTTP service method return values.
+		 * <p>By default this is {@link ReactiveAdapterRegistry#getSharedInstance()}.
+		 * @return this same builder instance
+		 */
+		public Builder reactiveAdapterRegistry(ReactiveAdapterRegistry registry) {
+			this.reactiveAdapterRegistry = registry;
+			return this;
+		}
+
+		/**
+		 * Configure how long to wait for a response for an HTTP service method
+		 * with a synchronous (blocking) method signature.
+		 * <p>By default this is 5 seconds.
+		 * @param blockTimeout the timeout value
+		 * @return this same builder instance
+		 */
+		public Builder blockTimeout(Duration blockTimeout) {
+			this.blockTimeout = blockTimeout;
+			return this;
+		}
+
+		/**
+		 * Build the {@link RSocketServiceProxyFactory} instance.
+		 */
+		public RSocketServiceProxyFactory build() {
+			Assert.notNull(this.rsocketRequester, "RSocketRequester is required");
+
+			return new RSocketServiceProxyFactory(
+					this.rsocketRequester, initArgumentResolvers(),
+					this.embeddedValueResolver, this.reactiveAdapterRegistry,
+					(this.blockTimeout != null ? this.blockTimeout : Duration.ofSeconds(5)));
+		}
+
+		private List<RSocketServiceArgumentResolver> initArgumentResolvers() {
+
+			// Custom
+			List<RSocketServiceArgumentResolver> resolvers = new ArrayList<>(this.customArgumentResolvers);
+
+			// Annotation-based
+			resolvers.add(new PayloadArgumentResolver(this.reactiveAdapterRegistry, false));
+			resolvers.add(new DestinationVariableArgumentResolver());
+
+			// Type-based
+			resolvers.add(new MetadataArgumentResolver());
+
+			// Fallback
+			resolvers.add(new PayloadArgumentResolver(this.reactiveAdapterRegistry, true));
+
+			return resolvers;
+		}
 	}
 
 
@@ -214,4 +329,163 @@ public final class RSocketServiceProxyFactory implements InitializingBean, Embed
 		}
 	}
 
+
+	/**
+	 * Temporary class until bean-style initialization is removed.
+	 */
+	private static final class BuilderInitializedFactory {
+
+		private final RSocketRequester rsocketRequester;
+
+		private final List<RSocketServiceArgumentResolver> argumentResolvers;
+
+		@Nullable
+		private final StringValueResolver embeddedValueResolver;
+
+		private final ReactiveAdapterRegistry reactiveAdapterRegistry;
+
+		private final Duration blockTimeout;
+
+
+		public BuilderInitializedFactory(
+				RSocketRequester rsocketRequester, List<RSocketServiceArgumentResolver> argumentResolvers,
+				@Nullable StringValueResolver embeddedValueResolver,
+				ReactiveAdapterRegistry reactiveAdapterRegistry, Duration blockTimeout) {
+
+			this.rsocketRequester = rsocketRequester;
+			this.argumentResolvers = argumentResolvers;
+			this.embeddedValueResolver = embeddedValueResolver;
+			this.reactiveAdapterRegistry = reactiveAdapterRegistry;
+			this.blockTimeout = blockTimeout;
+		}
+
+
+		public <S> S createClient(Class<S> serviceType) {
+
+			List<RSocketServiceMethod> serviceMethods =
+					MethodIntrospector.selectMethods(serviceType, this::isExchangeMethod).stream()
+							.map(method -> createRSocketServiceMethod(serviceType, method))
+							.toList();
+
+			return ProxyFactory.getProxy(serviceType, new ServiceMethodInterceptor(serviceMethods));
+		}
+
+		private boolean isExchangeMethod(Method method) {
+			return AnnotatedElementUtils.hasAnnotation(method, RSocketExchange.class);
+		}
+
+		private <S> RSocketServiceMethod createRSocketServiceMethod(Class<S> serviceType, Method method) {
+			Assert.notNull(this.argumentResolvers,
+					"No argument resolvers: afterPropertiesSet was not called");
+
+			return new RSocketServiceMethod(
+					method, serviceType, this.argumentResolvers, this.rsocketRequester,
+					this.embeddedValueResolver, this.reactiveAdapterRegistry, this.blockTimeout);
+		}
+	}
+
+
+	/**
+	 * Temporary class to support bean-style initialization during deprecation period.
+	 */
+	private static final class BeanStyleFactory implements InitializingBean, EmbeddedValueResolverAware {
+
+		private final RSocketRequester rsocketRequester;
+
+		@Nullable
+		private List<RSocketServiceArgumentResolver> customArgumentResolvers;
+
+		@Nullable
+		private List<RSocketServiceArgumentResolver> argumentResolvers;
+
+		@Nullable
+		private StringValueResolver embeddedValueResolver;
+
+		private ReactiveAdapterRegistry reactiveAdapterRegistry = ReactiveAdapterRegistry.getSharedInstance();
+
+		private Duration blockTimeout = Duration.ofSeconds(5);
+
+
+		public BeanStyleFactory(RSocketRequester rsocketRequester) {
+			Assert.notNull(rsocketRequester, "RSocketRequester is required");
+			this.rsocketRequester = rsocketRequester;
+		}
+
+
+		public void addCustomArgumentResolver(RSocketServiceArgumentResolver resolver) {
+			if (this.customArgumentResolvers == null) {
+				this.customArgumentResolvers = new ArrayList<>();
+			}
+			this.customArgumentResolvers.add(resolver);
+		}
+
+		public void setCustomArgumentResolvers(List<RSocketServiceArgumentResolver> resolvers) {
+			this.customArgumentResolvers = new ArrayList<>(resolvers);
+		}
+
+		@Override
+		public void setEmbeddedValueResolver(StringValueResolver resolver) {
+			this.embeddedValueResolver = resolver;
+		}
+
+		public void setReactiveAdapterRegistry(ReactiveAdapterRegistry registry) {
+			this.reactiveAdapterRegistry = registry;
+		}
+
+		public void setBlockTimeout(Duration blockTimeout) {
+			this.blockTimeout = blockTimeout;
+		}
+
+
+		@Override
+		public void afterPropertiesSet() {
+			this.argumentResolvers = initArgumentResolvers();
+		}
+
+		private List<RSocketServiceArgumentResolver> initArgumentResolvers() {
+			List<RSocketServiceArgumentResolver> resolvers = new ArrayList<>();
+
+			// Custom
+			if (this.customArgumentResolvers != null) {
+				resolvers.addAll(this.customArgumentResolvers);
+			}
+
+			// Annotation-based
+			resolvers.add(new PayloadArgumentResolver(this.reactiveAdapterRegistry, false));
+			resolvers.add(new DestinationVariableArgumentResolver());
+
+			// Type-based
+			resolvers.add(new MetadataArgumentResolver());
+
+			// Fallback
+			resolvers.add(new PayloadArgumentResolver(this.reactiveAdapterRegistry, true));
+
+			return resolvers;
+		}
+
+
+		public <S> S createClient(Class<S> serviceType) {
+
+			List<RSocketServiceMethod> serviceMethods =
+					MethodIntrospector.selectMethods(serviceType, this::isExchangeMethod).stream()
+							.map(method -> createRSocketServiceMethod(serviceType, method))
+							.toList();
+
+			return ProxyFactory.getProxy(serviceType, new ServiceMethodInterceptor(serviceMethods));
+		}
+
+		private boolean isExchangeMethod(Method method) {
+			return AnnotatedElementUtils.hasAnnotation(method, RSocketExchange.class);
+		}
+
+		private <S> RSocketServiceMethod createRSocketServiceMethod(Class<S> serviceType, Method method) {
+			Assert.notNull(this.argumentResolvers,
+					"No argument resolvers: afterPropertiesSet was not called");
+
+			return new RSocketServiceMethod(
+					method, serviceType, this.argumentResolvers, this.rsocketRequester,
+					this.embeddedValueResolver, this.reactiveAdapterRegistry, this.blockTimeout);
+		}
+	}
+
 }

spring-messaging/src/test/java/org/springframework/messaging/rsocket/service/RSocketServiceIntegrationTests.java

@@ -75,9 +75,7 @@ class RSocketServiceIntegrationTests {
 				.rsocketStrategies(context.getBean(RSocketStrategies.class))
 				.tcp("localhost", 7000);
 
-		RSocketServiceProxyFactory proxyFactory = new RSocketServiceProxyFactory(requester);
-		proxyFactory.afterPropertiesSet();
-
+		RSocketServiceProxyFactory proxyFactory = RSocketServiceProxyFactory.builder(requester).build();
 		serviceProxy = proxyFactory.createClient(Service.class);
 
 		context.close();

spring-messaging/src/test/java/org/springframework/messaging/rsocket/service/RSocketServiceMethodTests.java

@@ -47,11 +47,10 @@ public class RSocketServiceMethodTests {
 
 
 	@BeforeEach
-	public void setUp() throws Exception {
+	public void setUp() {
 		this.rsocket = new TestRSocket();
 		RSocketRequester requester = RSocketRequester.wrap(this.rsocket, TEXT_PLAIN, TEXT_PLAIN, RSocketStrategies.create());
-		this.proxyFactory = new RSocketServiceProxyFactory(requester);
-		this.proxyFactory.afterPropertiesSet();
+		this.proxyFactory = RSocketServiceProxyFactory.builder(requester).build();
 	}
 
 

spring-web/src/main/java/org/springframework/web/service/invoker/HttpServiceProxyFactory.java

@@ -64,10 +64,10 @@ public final class HttpServiceProxyFactory implements InitializingBean, Embedded
 	/**
 	 * Create an instance with the underlying HTTP client to use.
 	 * @param clientAdapter an adapter for the client
-	 * @deprecated as of 6.0 RC1 in favor of using the Builder to initialize
-	 * the HttpServiceProxyFactory instance.
+	 * @deprecated in favor of using the Builder to initialize the
+	 * HttpServiceProxyFactory instance.
 	 */
-	@Deprecated(since = "6.0.0-RC1", forRemoval = true)
+	@Deprecated(since = "6.0.0-RC2", forRemoval = true)
 	public HttpServiceProxyFactory(HttpClientAdapter clientAdapter) {
 		this.beanStyleFactory = new BeanStyleFactory(clientAdapter);
 		this.builderInitializedFactory = null;
@@ -87,10 +87,10 @@ public final class HttpServiceProxyFactory implements InitializingBean, Embedded
 	/**
 	 * Register a custom argument resolver, invoked ahead of default resolvers.
 	 * @param resolver the resolver to add
-	 * @deprecated as of 6.0 RC1 in favor of using the Builder to initialize
-	 * the HttpServiceProxyFactory instance.
+	 * @deprecated in favor of using the Builder to initialize the
+	 * HttpServiceProxyFactory instance.
 	 */
-	@Deprecated(since = "6.0.0-RC1", forRemoval = true)
+	@Deprecated(since = "6.0.0-RC2", forRemoval = true)
 	public void addCustomArgumentResolver(HttpServiceArgumentResolver resolver) {
 		Assert.state(this.beanStyleFactory != null, "HttpServiceProxyFactory was created through the builder");
 		this.beanStyleFactory.addCustomArgumentResolver(resolver);
@@ -99,10 +99,10 @@ public final class HttpServiceProxyFactory implements InitializingBean, Embedded
 	/**
 	 * Set the custom argument resolvers to use, ahead of default resolvers.
 	 * @param resolvers the resolvers to use
-	 * @deprecated as of 6.0 RC1 in favor of using the Builder to initialize
-	 * the HttpServiceProxyFactory instance.
+	 * @deprecated in favor of using the Builder to initialize the
+	 * HttpServiceProxyFactory instance.
 	 */
-	@Deprecated(since = "6.0.0-RC1", forRemoval = true)
+	@Deprecated(since = "6.0.0-RC2", forRemoval = true)
 	public void setCustomArgumentResolvers(List<HttpServiceArgumentResolver> resolvers) {
 		Assert.state(this.beanStyleFactory != null, "HttpServiceProxyFactory was created through the builder");
 		this.beanStyleFactory.setCustomArgumentResolvers(resolvers);
@@ -112,10 +112,10 @@ public final class HttpServiceProxyFactory implements InitializingBean, Embedded
 	 * Set the {@link ConversionService} to use where input values need to
 	 * be formatted as Strings.
 	 * <p>By default this is {@link DefaultFormattingConversionService}.
-	 * @deprecated as of 6.0 RC1 in favor of using the Builder to initialize
-	 * the HttpServiceProxyFactory instance.
+	 * @deprecated in favor of using the Builder to initialize the
+	 * HttpServiceProxyFactory instance.
 	 */
-	@Deprecated(since = "6.0.0-RC1", forRemoval = true)
+	@Deprecated(since = "6.0.0-RC2", forRemoval = true)
 	public void setConversionService(ConversionService conversionService) {
 		Assert.state(this.beanStyleFactory != null, "HttpServiceProxyFactory was created through the builder");
 		this.beanStyleFactory.setConversionService(conversionService);
@@ -125,10 +125,10 @@ public final class HttpServiceProxyFactory implements InitializingBean, Embedded
 	 * Set the StringValueResolver to use for resolving placeholders and
 	 * expressions in {@link HttpExchange#url()}.
 	 * @param resolver the resolver to use
-	 * @deprecated as of 6.0 RC1 in favor of using the Builder to initialize
-	 * an HttpServiceProxyFactory instance.
+	 * @deprecated in favor of using the Builder to initialize the
+	 * HttpServiceProxyFactory instance.
 	 */
-	@Deprecated(since = "6.0.0-RC1", forRemoval = true)
+	@Deprecated(since = "6.0.0-RC2", forRemoval = true)
 	@Override
 	public void setEmbeddedValueResolver(StringValueResolver resolver) {
 		Assert.state(this.beanStyleFactory != null, "HttpServiceProxyFactory was created through the builder");
@@ -139,10 +139,10 @@ public final class HttpServiceProxyFactory implements InitializingBean, Embedded
 	 * Set the {@link ReactiveAdapterRegistry} to use to support different
 	 * asynchronous types for HTTP service method return values.
 	 * <p>By default this is {@link ReactiveAdapterRegistry#getSharedInstance()}.
-	 * @deprecated as of 6.0 RC1 in favor of using the Builder to initialize
-	 * an HttpServiceProxyFactory instance.
+	 * @deprecated in favor of using the Builder to initialize the
+	 * HttpServiceProxyFactory instance.
 	 */
-	@Deprecated(since = "6.0.0-RC1", forRemoval = true)
+	@Deprecated(since = "6.0.0-RC2", forRemoval = true)
 	public void setReactiveAdapterRegistry(ReactiveAdapterRegistry registry) {
 		Assert.state(this.beanStyleFactory != null, "HttpServiceProxyFactory was created through the builder");
 		this.beanStyleFactory.setReactiveAdapterRegistry(registry);
@@ -153,10 +153,10 @@ public final class HttpServiceProxyFactory implements InitializingBean, Embedded
 	 * with a synchronous (blocking) method signature.
 	 * <p>By default this is 5 seconds.
 	 * @param blockTimeout the timeout value
-	 * @deprecated as of 6.0 RC1 in favor of using the Builder to initialize
-	 * an HttpServiceProxyFactory instance.
+	 * @deprecated in favor of using the Builder to initialize the
+	 * HttpServiceProxyFactory instance.
 	 */
-	@Deprecated(since = "6.0.0-RC1", forRemoval = true)
+	@Deprecated(since = "6.0.0-RC2", forRemoval = true)
 	public void setBlockTimeout(Duration blockTimeout) {
 		Assert.state(this.beanStyleFactory != null, "HttpServiceProxyFactory was created through the builder");
 		this.beanStyleFactory.setBlockTimeout(blockTimeout);
@@ -216,8 +216,7 @@ public final class HttpServiceProxyFactory implements InitializingBean, Embedded
 		@Nullable
 		private HttpClientAdapter clientAdapter;
 
-		@Nullable
-		private List<HttpServiceArgumentResolver> argumentResolvers;
+		private final List<HttpServiceArgumentResolver> customArgumentResolvers = new ArrayList<>();
 
 		@Nullable
 		private ConversionService conversionService;
@@ -249,8 +248,7 @@ public final class HttpServiceProxyFactory implements InitializingBean, Embedded
 		 * @return this same builder instance
 		 */
 		public Builder customArgumentResolver(HttpServiceArgumentResolver resolver) {
-			this.argumentResolvers = (this.argumentResolvers != null ? this.argumentResolvers : new ArrayList<>());
-			this.argumentResolvers.add(resolver);
+			this.customArgumentResolvers.add(resolver);
 			return this;
 		}
 
@@ -312,12 +310,9 @@ public final class HttpServiceProxyFactory implements InitializingBean, Embedded
 		}
 
 		private List<HttpServiceArgumentResolver> initArgumentResolvers() {
-			List<HttpServiceArgumentResolver> resolvers = new ArrayList<>();
 
 			// Custom
-			if (this.argumentResolvers != null) {
-				resolvers.addAll(this.argumentResolvers);
-			}
+			List<HttpServiceArgumentResolver> resolvers = new ArrayList<>(this.customArgumentResolvers);
 
 			ConversionService service = (this.conversionService != null ?
 					this.conversionService : new DefaultFormattingConversionService());
@@ -336,7 +331,6 @@ public final class HttpServiceProxyFactory implements InitializingBean, Embedded
 
 			return resolvers;
 		}
-
 	}
 
 
@@ -420,7 +414,6 @@ public final class HttpServiceProxyFactory implements InitializingBean, Embedded
 					method, serviceType, this.argumentResolvers, this.clientAdapter,
 					this.embeddedValueResolver, this.reactiveAdapterRegistry, this.blockTimeout);
 		}
-
 	}
 
 
@@ -536,7 +529,6 @@ public final class HttpServiceProxyFactory implements InitializingBean, Embedded
 					method, serviceType, this.argumentResolvers, this.clientAdapter,
 					this.embeddedValueResolver, this.reactiveAdapterRegistry, this.blockTimeout);
 		}
-
 	}
 
 }

src/docs/asciidoc/rsocket.adoc

@@ -935,8 +935,7 @@ Two, create a proxy that will perform the declared RSocket exchanges:
 [source,java,indent=0,subs="verbatim,quotes"]
 ----
 	RSocketRequester requester = ... ;
-	RSocketServiceProxyFactory factory = new RSocketServiceProxyFactory(requester);
-	factory.afterPropertiesSet();
+	RSocketServiceProxyFactory factory = RSocketServiceProxyFactory.builder(requester).build();
 
 	RepositoryService service = factory.createClient(RadarService.class);
 ----