Fine-tuned assertions and related polishing

spring-expression/src/main/java/org/springframework/expression/spel/standard/Tokenizer.java

@@ -265,7 +265,7 @@ class Tokenizer {
 						raiseParseException(this.pos, SpelMessage.UNEXPECTED_ESCAPE_CHAR);
 						break;
 					default:
-						throw new IllegalStateException("Cannot handle ('" + ch + "')");
+						throw new IllegalStateException("Cannot handle (" + (int) ch + ") '" + ch + "'");
 				}
 			}
 		}

spring-web/src/main/java/org/springframework/http/HttpHeaders.java

@@ -414,7 +414,6 @@ public class HttpHeaders implements MultiValueMap<String, String>, Serializable
 	 * Private constructor that can create read-only {@code HttpHeader} instances.
 	 */
 	private HttpHeaders(Map<String, List<String>> headers, boolean readOnly) {
-		Assert.notNull(headers, "'headers' must not be null");
 		if (readOnly) {
 			Map<String, List<String>> map = new LinkedCaseInsensitiveMap<>(headers.size(), Locale.ENGLISH);
 			headers.forEach((key, valueList) -> map.put(key, Collections.unmodifiableList(valueList)));
@@ -1556,6 +1555,7 @@ public class HttpHeaders implements MultiValueMap<String, String>, Serializable
 	 * Return a {@code HttpHeaders} object that can only be read, not written to.
 	 */
 	public static HttpHeaders readOnlyHttpHeaders(HttpHeaders headers) {
+		Assert.notNull(headers, "HttpHeaders must not be null");
 		return (headers.readOnly ? headers : new HttpHeaders(headers, true));
 	}
 

spring-webflux/src/main/java/org/springframework/web/reactive/function/client/ClientRequest.java

@@ -114,7 +114,7 @@ public interface ClientRequest {
 	/**
 	 * Create a builder with the given method and url.
 	 * @param method the HTTP method (GET, POST, etc)
-	 * @param url the URL
+	 * @param url the url (as a URI instance)
 	 * @return the created builder
 	 * @deprecated in favor of {@link #create(HttpMethod, URI)}
 	 */
@@ -126,7 +126,7 @@ public interface ClientRequest {
 	/**
 	 * Create a request builder with the given method and url.
 	 * @param method the HTTP method (GET, POST, etc)
-	 * @param url the URL
+	 * @param url the url (as a URI instance)
 	 * @return the created builder
 	 */
 	static Builder create(HttpMethod method, URI url) {

spring-webflux/src/main/java/org/springframework/web/reactive/function/client/DefaultClientRequestBuilder.java

@@ -49,28 +49,30 @@ import org.springframework.web.reactive.function.BodyInserters;
  */
 final class DefaultClientRequestBuilder implements ClientRequest.Builder {
 
+	private HttpMethod method;
+
+	private URI url;
+
 	private final HttpHeaders headers = new HttpHeaders();
 
 	private final MultiValueMap<String, String> cookies = new LinkedMultiValueMap<>();
 
 	private final Map<String, Object> attributes = new LinkedHashMap<>();
 
-	private HttpMethod method;
+	private BodyInserter<?, ? super ClientHttpRequest> body = BodyInserters.empty();
-
-	private URI url;
-
-	private BodyInserter<?, ? super ClientHttpRequest> inserter = BodyInserters.empty();
 
 
 	public DefaultClientRequestBuilder(HttpMethod method, URI url) {
-		method(method);
+		Assert.notNull(method, "HttpMethod must not be null");
-		url(url);
+		Assert.notNull(url, "URI must not be null");
+		this.method = method;
+		this.url = url;
 	}
 
 	public DefaultClientRequestBuilder(ClientRequest other) {
 		Assert.notNull(other, "ClientRequest must not be null");
-		method(other.method());
+		this.method = other.method();
-		url(other.url());
+		this.url = other.url();
 		headers(headers -> headers.addAll(other.headers()));
 		cookies(cookies -> cookies.addAll(other.cookies()));
 		attributes(attributes -> attributes.putAll(other.attributes()));
@@ -125,7 +127,7 @@ final class DefaultClientRequestBuilder implements ClientRequest.Builder {
 		Assert.notNull(publisher, "'publisher' must not be null");
 		Assert.notNull(elementClass, "'elementClass' must not be null");
 
-		this.inserter = BodyInserters.fromPublisher(publisher, elementClass);
+		this.body = BodyInserters.fromPublisher(publisher, elementClass);
 		return this;
 	}
 
@@ -136,7 +138,7 @@ final class DefaultClientRequestBuilder implements ClientRequest.Builder {
 		Assert.notNull(publisher, "'publisher' must not be null");
 		Assert.notNull(typeReference, "'typeReference' must not be null");
 
-		this.inserter = BodyInserters.fromPublisher(publisher, typeReference);
+		this.body = BodyInserters.fromPublisher(publisher, typeReference);
 		return this;
 	}
 
@@ -154,14 +156,13 @@ final class DefaultClientRequestBuilder implements ClientRequest.Builder {
 
 	@Override
 	public ClientRequest.Builder body(BodyInserter<?, ? super ClientHttpRequest> inserter) {
-		this.inserter = inserter;
+		this.body = inserter;
 		return this;
 	}
 
 	@Override
 	public ClientRequest build() {
-		return new BodyInserterRequest(this.method, this.url, this.headers, this.cookies,
+		return new BodyInserterRequest(this.method, this.url, this.headers, this.cookies, this.body, this.attributes);
-				this.inserter, this.attributes);
 	}
 
 
@@ -175,20 +176,19 @@ final class DefaultClientRequestBuilder implements ClientRequest.Builder {
 
 		private final MultiValueMap<String, String> cookies;
 
-		private final BodyInserter<?, ? super ClientHttpRequest> inserter;
+		private final BodyInserter<?, ? super ClientHttpRequest> body;
 
 		private final Map<String, Object> attributes;
 
 		public BodyInserterRequest(HttpMethod method, URI url, HttpHeaders headers,
-				MultiValueMap<String, String> cookies,
+				MultiValueMap<String, String> cookies, BodyInserter<?, ? super ClientHttpRequest> body,
-				BodyInserter<?, ? super ClientHttpRequest> inserter,
 				Map<String, Object> attributes) {
 
 			this.method = method;
 			this.url = url;
 			this.headers = HttpHeaders.readOnlyHttpHeaders(headers);
 			this.cookies = CollectionUtils.unmodifiableMultiValueMap(cookies);
-			this.inserter = inserter;
+			this.body = body;
 			this.attributes = Collections.unmodifiableMap(attributes);
 		}
 
@@ -214,7 +214,7 @@ final class DefaultClientRequestBuilder implements ClientRequest.Builder {
 
 		@Override
 		public BodyInserter<?, ? super ClientHttpRequest> body() {
-			return this.inserter;
+			return this.body;
 		}
 
 		@Override
@@ -240,17 +240,15 @@ final class DefaultClientRequestBuilder implements ClientRequest.Builder {
 				}));
 			}
 
-			return this.inserter.insert(request, new BodyInserter.Context() {
+			return this.body.insert(request, new BodyInserter.Context() {
 				@Override
 				public List<HttpMessageWriter<?>> messageWriters() {
 					return strategies.messageWriters();
 				}
-
 				@Override
 				public Optional<ServerHttpRequest> serverRequest() {
 					return Optional.empty();
 				}
-
 				@Override
 				public Map<String, Object> hints() {
 					return Collections.emptyMap();

spring-webflux/src/main/java/org/springframework/web/reactive/function/client/DefaultClientResponseBuilder.java

@@ -42,16 +42,16 @@ import org.springframework.util.MultiValueMap;
  */
 final class DefaultClientResponseBuilder implements ClientResponse.Builder {
 
+	private ExchangeStrategies strategies;
+
+	private HttpStatus statusCode = HttpStatus.OK;
+
 	private final HttpHeaders headers = new HttpHeaders();
 
 	private final MultiValueMap<String, ResponseCookie> cookies = new LinkedMultiValueMap<>();
 
-	private HttpStatus statusCode = HttpStatus.OK;
-
 	private Flux<DataBuffer> body = Flux.empty();
 
-	private ExchangeStrategies strategies;
-
 
 	public DefaultClientResponseBuilder(ExchangeStrategies strategies) {
 		Assert.notNull(strategies, "ExchangeStrategies must not be null");
@@ -84,7 +84,6 @@ final class DefaultClientResponseBuilder implements ClientResponse.Builder {
 
 	@Override
 	public ClientResponse.Builder headers(Consumer<HttpHeaders> headersConsumer) {
-		Assert.notNull(headersConsumer, "Consumer must not be null");
 		headersConsumer.accept(this.headers);
 		return this;
 	}
@@ -99,7 +98,6 @@ final class DefaultClientResponseBuilder implements ClientResponse.Builder {
 
 	@Override
 	public ClientResponse.Builder cookies(Consumer<MultiValueMap<String, ResponseCookie>> cookiesConsumer) {
-		Assert.notNull(cookiesConsumer, "Consumer must not be null");
 		cookiesConsumer.accept(this.cookies);
 		return this;
 	}

spring-webflux/src/main/java/org/springframework/web/reactive/function/client/DefaultWebClientBuilder.java

@@ -208,9 +208,7 @@ final class DefaultWebClientBuilder implements WebClient.Builder {
 
 	private static @Nullable HttpHeaders unmodifiableCopy(@Nullable HttpHeaders original) {
 		if (original != null) {
-			HttpHeaders copy = new HttpHeaders();
+			return HttpHeaders.readOnlyHttpHeaders(original);
-			copy.putAll(original);
-			return HttpHeaders.readOnlyHttpHeaders(copy);
 		}
 		else {
 			return null;

spring-webflux/src/main/java/org/springframework/web/reactive/function/server/DefaultEntityResponseBuilder.java

@@ -96,7 +96,6 @@ class DefaultEntityResponseBuilder<T> implements EntityResponse.Builder<T> {
 
 	@Override
 	public EntityResponse.Builder<T> cookies(Consumer<MultiValueMap<String, ResponseCookie>> cookiesConsumer) {
-		Assert.notNull(cookiesConsumer, "Consumer must not be null");
 		cookiesConsumer.accept(this.cookies);
 		return this;
 	}

spring-webflux/src/main/java/org/springframework/web/reactive/function/server/DefaultRenderingResponseBuilder.java

@@ -99,7 +99,6 @@ final class DefaultRenderingResponseBuilder implements RenderingResponse.Builder
 
 	@Override
 	public RenderingResponse.Builder cookies(Consumer<MultiValueMap<String, ResponseCookie>> cookiesConsumer) {
-		Assert.notNull(cookiesConsumer, "Consumer must not be null");
 		cookiesConsumer.accept(this.cookies);
 		return this;
 	}

spring-webflux/src/main/java/org/springframework/web/reactive/function/server/DefaultServerRequest.java

@@ -76,14 +76,10 @@ class DefaultServerRequest implements ServerRequest {
 
 	DefaultServerRequest(ServerWebExchange exchange, List<HttpMessageReader<?>> messageReaders) {
 		this.exchange = exchange;
-		this.messageReaders = unmodifiableCopy(messageReaders);
+		this.messageReaders = Collections.unmodifiableList(new ArrayList<>(messageReaders));
 		this.headers = new DefaultHeaders();
 	}
 
-	private static <T> List<T> unmodifiableCopy(List<? extends T> list) {
-		return Collections.unmodifiableList(new ArrayList<>(list));
-	}
-
 
 	@Override
 	public String methodName() {

spring-webflux/src/main/java/org/springframework/web/reactive/function/server/DefaultServerRequestBuilder.java

@@ -67,37 +67,39 @@ import org.springframework.web.util.UriUtils;
  */
 class DefaultServerRequestBuilder implements ServerRequest.Builder {
 
-	private final HttpHeaders headers = new HttpHeaders();
-
-	private final MultiValueMap<String, HttpCookie> cookies = new LinkedMultiValueMap<>();
-
-	private final Map<String, Object> attributes = new LinkedHashMap<>();
-
 	private final List<HttpMessageReader<?>> messageReaders;
 
 	private ServerWebExchange exchange;
 
-	private HttpMethod method = HttpMethod.GET;
+	private String methodName;
 
-	@Nullable
 	private URI uri;
 
+	private final HttpHeaders headers = new HttpHeaders();
+
+	private final MultiValueMap<String, HttpCookie> cookies = new LinkedMultiValueMap<>();
+
+	private final Map<String, Object> attributes = new LinkedHashMap<>();
+
 	private Flux<DataBuffer> body = Flux.empty();
 
+
 	public DefaultServerRequestBuilder(ServerRequest other) {
 		Assert.notNull(other, "ServerRequest must not be null");
 		this.messageReaders = other.messageReaders();
 		this.exchange = other.exchange();
-		method(other.method());
+		this.methodName = other.methodName();
-		uri(other.uri());
+		this.uri = other.uri();
 		headers(headers -> headers.addAll(other.headers().asHttpHeaders()));
 		cookies(cookies -> cookies.addAll(other.cookies()));
+		attributes(attributes -> attributes.putAll(other.attributes()));
 	}
 
+
 	@Override
 	public ServerRequest.Builder method(HttpMethod method) {
 		Assert.notNull(method, "'method' must not be null");
-		this.method = method;
+		this.methodName = method.name();
 		return this;
 	}
 
@@ -118,7 +120,6 @@ class DefaultServerRequestBuilder implements ServerRequest.Builder {
 
 	@Override
 	public ServerRequest.Builder headers(Consumer<HttpHeaders> headersConsumer) {
-		Assert.notNull(headersConsumer, "'headersConsumer' must not be null");
 		headersConsumer.accept(this.headers);
 		return this;
 	}
@@ -132,10 +133,7 @@ class DefaultServerRequestBuilder implements ServerRequest.Builder {
 	}
 
 	@Override
-	public ServerRequest.Builder cookies(
+	public ServerRequest.Builder cookies(Consumer<MultiValueMap<String, HttpCookie>> cookiesConsumer) {
-			Consumer<MultiValueMap<String, HttpCookie>> cookiesConsumer) {
-
-		Assert.notNull(cookiesConsumer, "'cookiesConsumer' must not be null");
 		cookiesConsumer.accept(this.cookies);
 		return this;
 	}
@@ -174,26 +172,25 @@ class DefaultServerRequestBuilder implements ServerRequest.Builder {
 
 	@Override
 	public ServerRequest.Builder attributes(Consumer<Map<String, Object>> attributesConsumer) {
-		Assert.notNull(attributesConsumer, "'attributesConsumer' must not be null");
 		attributesConsumer.accept(this.attributes);
 		return this;
 	}
 
 	@Override
 	public ServerRequest build() {
-		ServerHttpRequest serverHttpRequest = new BuiltServerHttpRequest(this.method, this.uri,
+		ServerHttpRequest serverHttpRequest = new BuiltServerHttpRequest(
-				this.headers, this.cookies, this.body);
+				this.methodName, this.uri, this.headers, this.cookies, this.body);
-		ServerWebExchange exchange = new DelegatingServerWebExchange(serverHttpRequest,
+		ServerWebExchange exchange = new DelegatingServerWebExchange(
-				this.exchange, this.messageReaders);
+				serverHttpRequest, this.exchange, this.messageReaders);
 		return new DefaultServerRequest(exchange, this.messageReaders);
 	}
 
+
 	private static class BuiltServerHttpRequest implements ServerHttpRequest {
 
 		private static final Pattern QUERY_PATTERN = Pattern.compile("([^&=]+)(=?)([^&]+)?");
 
-
+		private final String method;
-		private final HttpMethod method;
 
 		private final URI uri;
 
@@ -207,10 +204,9 @@ class DefaultServerRequestBuilder implements ServerRequest.Builder {
 
 		private final Flux<DataBuffer> body;
 
-		public BuiltServerHttpRequest(HttpMethod method, URI uri,
+		public BuiltServerHttpRequest(String method, URI uri, HttpHeaders headers,
-				HttpHeaders headers,
+				MultiValueMap<String, HttpCookie> cookies, Flux<DataBuffer> body) {
-				MultiValueMap<String, HttpCookie> cookies,
+
-				Flux<DataBuffer> body) {
 			this.method = method;
 			this.uri = uri;
 			this.path = RequestPath.parse(uri, null);
@@ -245,15 +241,9 @@ class DefaultServerRequestBuilder implements ServerRequest.Builder {
 			return queryParams;
 		}
 
-		@Nullable
-		@Override
-		public HttpMethod getMethod() {
-			return this.method;
-		}
-
 		@Override
 		public String getMethodValue() {
-			return this.method.name();
+			return this.method;
 		}
 
 		@Override
@@ -287,6 +277,7 @@ class DefaultServerRequestBuilder implements ServerRequest.Builder {
 		}
 	}
 
+
 	private static class DelegatingServerWebExchange implements ServerWebExchange {
 
 		private static final ResolvableType FORM_DATA_TYPE =
@@ -296,12 +287,10 @@ class DefaultServerRequestBuilder implements ServerRequest.Builder {
 				MultiValueMap.class, String.class, Part.class);
 
 		private static final Mono<MultiValueMap<String, String>> EMPTY_FORM_DATA =
-				Mono.just(CollectionUtils.unmodifiableMultiValueMap(new LinkedMultiValueMap<String, String>(0)))
+				Mono.just(CollectionUtils.unmodifiableMultiValueMap(new LinkedMultiValueMap<String, String>(0))).cache();
-						.cache();
 
 		private static final Mono<MultiValueMap<String, Part>> EMPTY_MULTIPART_DATA =
-				Mono.just(CollectionUtils.unmodifiableMultiValueMap(new LinkedMultiValueMap<String, Part>(0)))
+				Mono.just(CollectionUtils.unmodifiableMultiValueMap(new LinkedMultiValueMap<String, Part>(0))).cache();
-						.cache();
 
 		private final ServerHttpRequest request;
 
@@ -311,8 +300,9 @@ class DefaultServerRequestBuilder implements ServerRequest.Builder {
 
 		private final Mono<MultiValueMap<String, Part>> multipartDataMono;
 
-		public DelegatingServerWebExchange(ServerHttpRequest request, ServerWebExchange delegate,
+		public DelegatingServerWebExchange(
-				List<HttpMessageReader<?>> messageReaders) {
+				ServerHttpRequest request, ServerWebExchange delegate, List<HttpMessageReader<?>> messageReaders) {
+
 			this.request = request;
 			this.delegate = delegate;
 			this.formDataMono = initFormData(request, messageReaders);
@@ -399,7 +389,6 @@ class DefaultServerRequestBuilder implements ServerRequest.Builder {
 			return this.delegate.getPrincipal();
 		}
 
-
 		@Override
 		public LocaleContext getLocaleContext() {
 			return this.delegate.getLocaleContext();

spring-webflux/src/main/java/org/springframework/web/reactive/function/server/DefaultServerResponseBuilder.java

@@ -97,7 +97,6 @@ class DefaultServerResponseBuilder implements ServerResponse.BodyBuilder {
 
 	@Override
 	public ServerResponse.BodyBuilder headers(Consumer<HttpHeaders> headersConsumer) {
-		Assert.notNull(headersConsumer, "Consumer must not be null");
 		headersConsumer.accept(this.headers);
 		return this;
 	}
@@ -111,7 +110,6 @@ class DefaultServerResponseBuilder implements ServerResponse.BodyBuilder {
 
 	@Override
 	public ServerResponse.BodyBuilder cookies(Consumer<MultiValueMap<String, ResponseCookie>> cookiesConsumer) {
-		Assert.notNull(cookiesConsumer, "Consumer must not be null");
 		cookiesConsumer.accept(this.cookies);
 		return this;
 	}
@@ -201,9 +199,8 @@ class DefaultServerResponseBuilder implements ServerResponse.BodyBuilder {
 	public Mono<ServerResponse> build(
 			BiFunction<ServerWebExchange, ServerResponse.Context, Mono<Void>> writeFunction) {
 
-		Assert.notNull(writeFunction, "BiFunction must not be null");
 		return Mono.just(
-				new WriterFunctionServerResponse(this.statusCode, this.headers, this.cookies, writeFunction));
+				new WriterFunctionResponse(this.statusCode, this.headers, this.cookies, writeFunction));
 	}
 
 	@Override
@@ -250,15 +247,12 @@ class DefaultServerResponseBuilder implements ServerResponse.BodyBuilder {
 
 	@Override
 	public Mono<ServerResponse> body(BodyInserter<?, ? super ServerHttpResponse> inserter) {
-		Assert.notNull(inserter, "BodyInserter must not be null");
 		return Mono.just(
-				new BodyInserterServerResponse<>(this.statusCode, this.headers, this.cookies, inserter, this.hints));
+				new BodyInserterResponse<>(this.statusCode, this.headers, this.cookies, inserter, this.hints));
 	}
 
 	@Override
 	public Mono<ServerResponse> render(String name, Object... modelAttributes) {
-		Assert.hasLength(name, "Name must not be empty");
-
 		return new DefaultRenderingResponseBuilder(name)
 				.headers(this.headers)
 				.status(this.statusCode)
@@ -269,8 +263,6 @@ class DefaultServerResponseBuilder implements ServerResponse.BodyBuilder {
 
 	@Override
 	public Mono<ServerResponse> render(String name, Map<String, ?> model) {
-		Assert.hasLength(name, "Name must not be empty");
-
 		return new DefaultRenderingResponseBuilder(name)
 				.headers(this.headers)
 				.status(this.statusCode)
@@ -290,24 +282,12 @@ class DefaultServerResponseBuilder implements ServerResponse.BodyBuilder {
 
 		private final MultiValueMap<String, ResponseCookie> cookies;
 
-		protected AbstractServerResponse(int statusCode, HttpHeaders headers,
+		protected AbstractServerResponse(
-				MultiValueMap<String, ResponseCookie> cookies) {
+				int statusCode, HttpHeaders headers, MultiValueMap<String, ResponseCookie> cookies) {
 
 			this.statusCode = statusCode;
-			this.headers = readOnlyCopy(headers);
+			this.headers = HttpHeaders.readOnlyHttpHeaders(headers);
-			this.cookies = readOnlyCopy(cookies);
+			this.cookies = CollectionUtils.unmodifiableMultiValueMap(new LinkedMultiValueMap<>(cookies));
-		}
-
-		private static HttpHeaders readOnlyCopy(HttpHeaders headers) {
-			HttpHeaders copy = new HttpHeaders();
-			copy.putAll(headers);
-			return HttpHeaders.readOnlyHttpHeaders(copy);
-		}
-
-		private static <K, V> MultiValueMap<K,V> readOnlyCopy(MultiValueMap<K, V> map) {
-			MultiValueMap<K, V> copy = new LinkedMultiValueMap<>();
-			copy.putAll(map);
-			return CollectionUtils.unmodifiableMultiValueMap(copy);
 		}
 
 		@Override
@@ -367,15 +347,16 @@ class DefaultServerResponseBuilder implements ServerResponse.BodyBuilder {
 	}
 
 
-	private static final class WriterFunctionServerResponse extends AbstractServerResponse {
+	private static final class WriterFunctionResponse extends AbstractServerResponse {
 
 		private final BiFunction<ServerWebExchange, Context, Mono<Void>> writeFunction;
 
-		public WriterFunctionServerResponse(int statusCode, HttpHeaders headers,
+		public WriterFunctionResponse(int statusCode, HttpHeaders headers,
 				MultiValueMap<String, ResponseCookie> cookies,
 				BiFunction<ServerWebExchange, Context, Mono<Void>> writeFunction) {
 
 			super(statusCode, headers, cookies);
+			Assert.notNull(writeFunction, "BiFunction must not be null");
 			this.writeFunction = writeFunction;
 		}
 
@@ -386,18 +367,19 @@ class DefaultServerResponseBuilder implements ServerResponse.BodyBuilder {
 	}
 
 
-	private static final class BodyInserterServerResponse<T> extends AbstractServerResponse {
+	private static final class BodyInserterResponse<T> extends AbstractServerResponse {
 
 		private final BodyInserter<T, ? super ServerHttpResponse> inserter;
 
 		private final Map<String, Object> hints;
 
-		public BodyInserterServerResponse(int statusCode, HttpHeaders headers,
+		public BodyInserterResponse(int statusCode, HttpHeaders headers,
 				MultiValueMap<String, ResponseCookie> cookies,
-				BodyInserter<T, ? super ServerHttpResponse> inserter, Map<String, Object> hints) {
+				BodyInserter<T, ? super ServerHttpResponse> body, Map<String, Object> hints) {
 
 			super(statusCode, headers, cookies);
-			this.inserter = inserter;
+			Assert.notNull(body, "BodyInserter must not be null");
+			this.inserter = body;
 			this.hints = hints;
 		}
 

spring-webflux/src/main/java/org/springframework/web/reactive/function/server/ServerRequest.java

@@ -43,7 +43,6 @@ import org.springframework.http.codec.multipart.Part;
 import org.springframework.http.server.PathContainer;
 import org.springframework.http.server.reactive.ServerHttpRequest;
 import org.springframework.lang.Nullable;
-import org.springframework.util.Assert;
 import org.springframework.util.CollectionUtils;
 import org.springframework.util.MultiValueMap;
 import org.springframework.web.reactive.function.BodyExtractor;
@@ -125,6 +124,7 @@ public interface ServerRequest {
 
 	/**
 	 * Return the readers used to convert the body of this request.
+	 * @since 5.1
 	 */
 	List<HttpMessageReader<?>> messageReaders();
 
@@ -262,7 +262,6 @@ public interface ServerRequest {
 	/**
 	 * Return the form data from the body of the request if the Content-Type is
 	 * {@code "application/x-www-form-urlencoded"} or an empty map otherwise.
-	 *
 	 * <p><strong>Note:</strong> calling this method causes the request body to
 	 * be read and parsed in full and the resulting {@code MultiValueMap} is
 	 * cached so that this method is safe to call more than once.
@@ -272,7 +271,6 @@ public interface ServerRequest {
 	/**
 	 * Return the parts of a multipart request if the Content-Type is
 	 * {@code "multipart/form-data"} or an empty map otherwise.
-	 *
 	 * <p><strong>Note:</strong> calling this method causes the request body to
 	 * be read and parsed in full and the resulting {@code MultiValueMap} is
 	 * cached so that this method is safe to call more than once.
@@ -280,14 +278,14 @@ public interface ServerRequest {
 	Mono<MultiValueMap<String, Part>> multipartData();
 
 	/**
-	 * Returns the web exchange that this request is based on. Manipulating the exchange directly,
+	 * Return the web exchange that this request is based on.
-	 * instead of using the methods provided on {@code ServerRequest} and {@code ServerResponse},
+	 * <p>Note: Manipulating the exchange directly (instead of using the methods provided on
-	 * can lead to irregular results.
+	 * {@code ServerRequest} and {@code ServerResponse}) can lead to irregular results.
-	 *
+	 * @since 5.1
-	 * @return the web exchange
 	 */
 	ServerWebExchange exchange();
 
+
 	// Static methods
 
 	/**
@@ -305,12 +303,13 @@ public interface ServerRequest {
 	 * Create a builder with the status, headers, and cookies of the given request.
 	 * @param other the response to copy the status, headers, and cookies from
 	 * @return the created builder
+	 * @since 5.1
 	 */
 	static Builder from(ServerRequest other) {
-		Assert.notNull(other, "'other' must not be null");
 		return new DefaultServerRequestBuilder(other);
 	}
 
+
 	/**
 	 * Represents the headers of the HTTP request.
 	 * @see ServerRequest#headers()
@@ -378,6 +377,7 @@ public interface ServerRequest {
 
 	/**
 	 * Defines a builder for a request.
+	 * @since 5.1
 	 */
 	interface Builder {
 

spring-webmvc/src/test/java/org/springframework/web/servlet/mvc/method/annotation/ResponseEntityExceptionHandlerTests.java

@@ -328,6 +328,8 @@ public class ResponseEntityExceptionHandlerTests {
 		}
 	}
 
+
+	@SuppressWarnings("unused")
 	void handle(String arg) {
 	}