Polish server request & response implementations

spring-web-reactive/src/main/java/org/springframework/http/ExtendedHttpHeaders.java

@@ -21,10 +21,11 @@ import java.util.List;
 import java.util.Map;
 
 /**
- * Extension of HttpHeaders (to be merged into HttpHeaders) that allows the
- * registration of {@link HeaderChangeListener}. For use with HTTP response
- * implementations that can keep track of changes made headers and keep the
- * underlying server headers always in sync.
+ * Variant of HttpHeaders (to be merged into HttpHeaders) that supports the
+ * registration of {@link HeaderChangeListener}s.
+ *
+ * <p>For use with HTTP server response implementations that wish to propagate
+ * header header changes to the underlying runtime as they occur.
  *
  * @author Rossen Stoyanchev
  */
@@ -33,7 +34,10 @@ public class ExtendedHttpHeaders extends HttpHeaders {
 	private final List<HeaderChangeListener> listeners = new ArrayList<>(1);
 
 
-	public void registerChangeListener(HeaderChangeListener listener) {
+	public ExtendedHttpHeaders() {
+	}
+
+	public ExtendedHttpHeaders(HeaderChangeListener listener) {
 		this.listeners.add(listener);
 	}
 
@@ -48,7 +52,7 @@ public class ExtendedHttpHeaders extends HttpHeaders {
 
 	@Override
 	public void set(String name, String value) {
-		List<String> values = new LinkedList<String>();
+		List<String> values = new LinkedList<>();
 		values.add(value);
 		put(name, values);
 	}

spring-web-reactive/src/main/java/org/springframework/http/ReactiveHttpInputMessage.java

@@ -21,11 +21,9 @@ import java.nio.ByteBuffer;
 import org.reactivestreams.Publisher;
 
 /**
- * Represents a "reactive" HTTP input message, consisting of
- * {@linkplain #getHeaders() headers} and a readable
- * {@linkplain #getBody() streaming body }.
+ * An "reactive" HTTP input message that exposes the input as {@link Publisher}.
  *
- * <p>Typically implemented by an HTTP request on the server-side, or a response
+ * <p>Typically implemented by an HTTP request on the server-side or a response
  * on the client-side.
  *
  * @author Arjen Poutsma
@@ -33,8 +31,8 @@ import org.reactivestreams.Publisher;
 public interface ReactiveHttpInputMessage extends HttpMessage {
 
 	/**
-	 * Return the body of the message as an publisher of {@code ByteBuffer}s.
-	 * @return the body
+	 * Return the body of the message as a {@link Publisher}.
+	 * @return the body content publisher
 	 */
 	Publisher<ByteBuffer> getBody();
 

spring-web-reactive/src/main/java/org/springframework/http/ReactiveHttpOutputMessage.java

@@ -21,11 +21,9 @@ import java.nio.ByteBuffer;
 import org.reactivestreams.Publisher;
 
 /**
- * Represents a "reactive" HTTP output message, consisting of
- * {@linkplain #getHeaders() headers} and the capability to add a
- * {@linkplain #setBody(Publisher) body}.
+ * A "reactive" HTTP output message that accepts output as a {@link Publisher}.
  *
- * <p>Typically implemented by an HTTP request on the client-side, or a response
+ * <p>Typically implemented by an HTTP request on the client-side or a response
  * on the server-side.
  *
  * @author Arjen Poutsma
@@ -33,12 +31,11 @@ import org.reactivestreams.Publisher;
 public interface ReactiveHttpOutputMessage extends HttpMessage {
 
 	/**
-	 * Sets the body of this message to the given publisher of {@link ByteBuffer}s.
-	 * The publisher will be used to write to the underlying HTTP layer with
-	 * asynchronously, given pull demand by this layer.
+	 * Set the body of the message to the given {@link Publisher} which will be
+	 * used to write to the underlying HTTP layer.
 	 *
-	 * @param body the body to use
-	 * @return a publisher that indicates completion
+	 * @param body the body content publisher
+	 * @return a publisher that indicates completion or error.
 	 */
 	Publisher<Void> setBody(Publisher<ByteBuffer> body);
 

spring-web-reactive/src/main/java/org/springframework/http/server/reactive/ReactorServerHttpRequest.java

@@ -26,36 +26,30 @@ import reactor.io.net.http.HttpChannel;
 
 import org.springframework.http.HttpHeaders;
 import org.springframework.http.HttpMethod;
-import org.springframework.http.server.reactive.ServerHttpRequest;
 import org.springframework.util.Assert;
 
 /**
+ * Adapt {@link ServerHttpRequest} to the Reactor Net {@link HttpChannel}.
+ *
  * @author Stephane Maldini
  */
 public class ReactorServerHttpRequest implements ServerHttpRequest {
 
 	private final HttpChannel<Buffer, ?> channel;
 
+	private URI uri;
+
 	private HttpHeaders headers;
 
 
 	public ReactorServerHttpRequest(HttpChannel<Buffer, ?> request) {
-		Assert.notNull("'request', request must not be null.");
+		Assert.notNull("'request' must not be null.");
 		this.channel = request;
 	}
 
 
-	@Override
-	public HttpHeaders getHeaders() {
-		if (this.headers == null) {
-			this.headers = new HttpHeaders();
-			for (String name : this.channel.headers().names()) {
-				for (String value : this.channel.headers().getAll(name)) {
-					this.headers.add(name, value);
-				}
-			}
-		}
-		return this.headers;
+	public HttpChannel<Buffer, ?> getReactorChannel() {
+		return this.channel;
 	}
 
 	@Override
@@ -65,12 +59,26 @@ public class ReactorServerHttpRequest implements ServerHttpRequest {
 
 	@Override
 	public URI getURI() {
-		try {
-			return new URI(this.channel.uri());
-		} catch (URISyntaxException ex) {
-			throw new IllegalStateException("Could not get URI: " + ex.getMessage(), ex);
+		if (this.uri == null) {
+			try {
+				this.uri = new URI(this.channel.uri());
+			}
+			catch (URISyntaxException ex) {
+				throw new IllegalStateException("Could not get URI: " + ex.getMessage(), ex);
+			}
 		}
+		return this.uri;
+	}
 
+	@Override
+	public HttpHeaders getHeaders() {
+		if (this.headers == null) {
+			this.headers = new HttpHeaders();
+			for (String name : this.channel.headers().names()) {
+				this.headers.put(name, this.channel.headers().getAll(name));
+			}
+		}
+		return this.headers;
 	}
 
 	@Override

spring-web-reactive/src/main/java/org/springframework/http/server/reactive/ReactorServerHttpResponse.java

@@ -30,6 +30,8 @@ import org.springframework.http.HttpStatus;
 import org.springframework.util.Assert;
 
 /**
+ * Adapt {@link ServerHttpResponse} to the Reactor Net {@link HttpChannel}.
+ *
  * @author Stephane Maldini
  * @author Rossen Stoyanchev
  */
@@ -41,21 +43,19 @@ public class ReactorServerHttpResponse implements ServerHttpResponse {
 
 
 	public ReactorServerHttpResponse(HttpChannel<?, Buffer> response) {
-		Assert.notNull("'response', response must not be null.");
+		Assert.notNull("'response' must not be null.");
 		this.channel = response;
-		this.headers = initHttpHeaders();
+		this.headers = new ExtendedHttpHeaders(new ReactorHeaderChangeListener());
 	}
 
-	private HttpHeaders initHttpHeaders() {
-		ExtendedHttpHeaders headers = new ExtendedHttpHeaders();
-		headers.registerChangeListener(new ReactorHeaderChangeListener());
-		return headers;
-	}
 
+	public HttpChannel<?, Buffer> getReactorChannel() {
+		return this.channel;
+	}
 
 	@Override
 	public void setStatusCode(HttpStatus status) {
-		this.channel.responseStatus(Status.valueOf(status.value()));
+		getReactorChannel().responseStatus(Status.valueOf(status.value()));
 	}
 
 	@Override
@@ -65,8 +65,11 @@ public class ReactorServerHttpResponse implements ServerHttpResponse {
 
 	@Override
 	public Publisher<Void> setBody(Publisher<ByteBuffer> publisher) {
-		return Publishers.lift(publisher, new WriteWithOperator<>(writePublisher ->
-				this.channel.writeWith(Publishers.map(writePublisher, Buffer::new))));
+		return Publishers.lift(publisher, new WriteWithOperator<>(this::setBodyInternal));
+	}
+
+	protected Publisher<Void> setBodyInternal(Publisher<ByteBuffer> publisher) {
+		return getReactorChannel().writeWith(Publishers.map(publisher, Buffer::new));
 	}
 
 
@@ -74,18 +77,18 @@ public class ReactorServerHttpResponse implements ServerHttpResponse {
 
 		@Override
 		public void headerAdded(String name, String value) {
-			channel.responseHeaders().add(name, value);
+			getReactorChannel().responseHeaders().add(name, value);
 		}
 
 		@Override
 		public void headerPut(String key, List<String> values) {
-			channel.responseHeaders().remove(key);
-			channel.responseHeaders().add(key, values);
+			getReactorChannel().responseHeaders().remove(key);
+			getReactorChannel().responseHeaders().add(key, values);
 		}
 
 		@Override
 		public void headerRemoved(String key) {
-			channel.responseHeaders().remove(key);
+			getReactorChannel().responseHeaders().remove(key);
 		}
 	}
 

spring-web-reactive/src/main/java/org/springframework/http/server/reactive/RxNettyServerHttpRequest.java

@@ -31,6 +31,8 @@ import org.springframework.http.HttpMethod;
 import org.springframework.util.Assert;
 
 /**
+ * Adapt {@link ServerHttpRequest} to the RxNetty {@link HttpServerRequest}.
+ *
  * @author Rossen Stoyanchev
  * @author Stephane Maldini
  */
@@ -38,6 +40,8 @@ public class RxNettyServerHttpRequest implements ServerHttpRequest {
 
 	private final HttpServerRequest<ByteBuf> request;
 
+	private URI uri;
+
 	private HttpHeaders headers;
 
 
@@ -47,44 +51,44 @@ public class RxNettyServerHttpRequest implements ServerHttpRequest {
 	}
 
 
+	public HttpServerRequest<ByteBuf> getRxNettyRequest() {
+		return this.request;
+	}
+
+	@Override
+	public HttpMethod getMethod() {
+		return HttpMethod.valueOf(this.getRxNettyRequest().getHttpMethod().name());
+	}
+
+	@Override
+	public URI getURI() {
+		if (this.uri == null) {
+			try {
+				this.uri = new URI(this.getRxNettyRequest().getUri());
+			}
+			catch (URISyntaxException ex) {
+				throw new IllegalStateException("Could not get URI: " + ex.getMessage(), ex);
+			}
+		}
+		return this.uri;
+	}
+
 	@Override
 	public HttpHeaders getHeaders() {
 		if (this.headers == null) {
 			this.headers = new HttpHeaders();
-			for (String name : this.request.getHeaderNames()) {
-				for (String value : this.request.getAllHeaderValues(name)) {
-					this.headers.add(name, value);
-				}
+			for (String name : this.getRxNettyRequest().getHeaderNames()) {
+				this.headers.put(name, this.getRxNettyRequest().getAllHeaderValues(name));
 			}
 		}
 		return this.headers;
 	}
 
-	@Override
-	public HttpMethod getMethod() {
-		return HttpMethod.valueOf(this.request.getHttpMethod().name());
-	}
-
-	@Override
-	public URI getURI() {
-		try {
-			return new URI(this.request.getUri());
-		}
-		catch (URISyntaxException ex) {
-			throw new IllegalStateException("Could not get URI: " + ex.getMessage(), ex);
-		}
-
-	}
-
 	@Override
 	public Publisher<ByteBuffer> getBody() {
-		Observable<ByteBuffer> bytesContent = this.request.getContent()
-				.concatWith(Observable.empty())
-				.map(ByteBuf::nioBuffer);
-		return RxJava1Converter.from(bytesContent);
+		Observable<ByteBuffer> content = this.getRxNettyRequest().getContent().map(ByteBuf::nioBuffer);
+		content = content.concatWith(Observable.empty()); // See GH issue #58
+		return RxJava1Converter.from(content);
 	}
 
-	public Observable<ByteBuffer> asObservable() {
-		return this.request.getContent().map(ByteBuf::nioBuffer);
-	}
 }

spring-web-reactive/src/main/java/org/springframework/http/server/reactive/RxNettyServerHttpResponse.java

@@ -32,6 +32,8 @@ import org.springframework.http.HttpStatus;
 import org.springframework.util.Assert;
 
 /**
+ * Adapt {@link ServerHttpResponse} to the RxNetty {@link HttpServerResponse}.
+ *
  * @author Rossen Stoyanchev
  * @author Stephane Maldini
  */
@@ -45,19 +47,17 @@ public class RxNettyServerHttpResponse implements ServerHttpResponse {
 	public RxNettyServerHttpResponse(HttpServerResponse<?> response) {
 		Assert.notNull("'response', response must not be null.");
 		this.response = response;
-		this.headers = initHttpHeaders();
+		this.headers = new ExtendedHttpHeaders(new RxNettyHeaderChangeListener());
 	}
 
-	private HttpHeaders initHttpHeaders() {
-		ExtendedHttpHeaders headers = new ExtendedHttpHeaders();
-		headers.registerChangeListener(new RxNettyHeaderChangeListener());
-		return headers;
-	}
 
+	public HttpServerResponse<?> getRxNettyResponse() {
+		return this.response;
+	}
 
 	@Override
 	public void setStatusCode(HttpStatus status) {
-		this.response.setStatus(HttpResponseStatus.valueOf(status.value()));
+		getRxNettyResponse().setStatus(HttpResponseStatus.valueOf(status.value()));
 	}
 
 	@Override
@@ -67,15 +67,19 @@ public class RxNettyServerHttpResponse implements ServerHttpResponse {
 
 	@Override
 	public Publisher<Void> setBody(Publisher<ByteBuffer> publisher) {
-		return Publishers.lift(publisher, new WriteWithOperator<>(writePublisher -> {
-			Observable<byte[]> observable = RxJava1Converter.from(writePublisher)
-					.map(buffer -> {
-						byte[] bytes = new byte[buffer.remaining()];
-						buffer.get(bytes);
-						return bytes;
-					});
-			return RxJava1Converter.from(this.response.writeBytes(observable));
-		}));
+		return Publishers.lift(publisher, new WriteWithOperator<>(this::setBodyInternal));
+	}
+
+	protected Publisher<Void> setBodyInternal(Publisher<ByteBuffer> publisher) {
+		Observable<byte[]> content = RxJava1Converter.from(publisher).map(this::toBytes);
+		Observable<Void> completion = getRxNettyResponse().writeBytes(content);
+		return RxJava1Converter.from(completion);
+	}
+
+	private byte[] toBytes(ByteBuffer buffer) {
+		byte[] bytes = new byte[buffer.remaining()];
+		buffer.get(bytes);
+		return bytes;
 	}
 
 
@@ -83,20 +87,20 @@ public class RxNettyServerHttpResponse implements ServerHttpResponse {
 
 		@Override
 		public void headerAdded(String name, String value) {
-			response.addHeader(name, value);
+			getRxNettyResponse().addHeader(name, value);
 		}
 
 		@Override
 		public void headerPut(String key, List<String> values) {
-			response.removeHeader(key);
+			getRxNettyResponse().removeHeader(key);
 			for (String value : values) {
-				response.addHeader(key, value);
+				getRxNettyResponse().addHeader(key, value);
 			}
 		}
 
 		@Override
 		public void headerRemoved(String key) {
-			response.removeHeader(key);
+			getRxNettyResponse().removeHeader(key);
 		}
 	}
 

spring-web-reactive/src/main/java/org/springframework/http/server/reactive/ServletServerHttpRequest.java

@@ -43,6 +43,8 @@ import org.springframework.util.LinkedCaseInsensitiveMap;
 import org.springframework.util.StringUtils;
 
 /**
+ * Adapt {@link ServerHttpRequest} to the Servlet {@link HttpServletRequest}.
+ *
  * @author Rossen Stoyanchev
  */
 public class ServletServerHttpRequest implements ServerHttpRequest {
@@ -52,44 +54,55 @@ public class ServletServerHttpRequest implements ServerHttpRequest {
 	private static final Log logger = LogFactory.getLog(ServletServerHttpRequest.class);
 
 
-	private final HttpServletRequest servletRequest;
+	private final HttpServletRequest request;
+
+	private URI uri;
 
 	private HttpHeaders headers;
 
 	private final RequestBodyPublisher requestBodyPublisher;
 
 
-	public ServletServerHttpRequest(HttpServletRequest servletRequest, ServletAsyncContextSynchronizer synchronizer) {
-		Assert.notNull(servletRequest, "HttpServletRequest must not be null");
-		this.servletRequest = servletRequest;
+	public ServletServerHttpRequest(HttpServletRequest request, ServletAsyncContextSynchronizer synchronizer) {
+		Assert.notNull(request, "'request' must not be null.");
+		this.request = request;
 		this.requestBodyPublisher = new RequestBodyPublisher(synchronizer, BUFFER_SIZE);
 	}
 
 
+	public HttpServletRequest getServletRequest() {
+		return this.request;
+	}
+
 	@Override
 	public HttpMethod getMethod() {
-		return HttpMethod.valueOf(this.servletRequest.getMethod());
+		return HttpMethod.valueOf(getServletRequest().getMethod());
 	}
 
 	@Override
 	public URI getURI() {
-		try {
-			return new URI(this.servletRequest.getScheme(), null, this.servletRequest.getServerName(),
-					this.servletRequest.getServerPort(), this.servletRequest.getRequestURI(),
-					this.servletRequest.getQueryString(), null);
-		}
-		catch (URISyntaxException ex) {
-			throw new IllegalStateException("Could not get HttpServletRequest URI: " + ex.getMessage(), ex);
+		if (this.uri == null) {
+			try {
+				this.uri = new URI(getServletRequest().getScheme(), null,
+						getServletRequest().getServerName(),
+						getServletRequest().getServerPort(),
+						getServletRequest().getRequestURI(),
+						getServletRequest().getQueryString(), null);
+			}
+			catch (URISyntaxException ex) {
+				throw new IllegalStateException("Could not get HttpServletRequest URI: " + ex.getMessage(), ex);
+			}
 		}
+		return this.uri;
 	}
 
 	@Override
 	public HttpHeaders getHeaders() {
 		if (this.headers == null) {
 			this.headers = new HttpHeaders();
-			for (Enumeration<?> names = this.servletRequest.getHeaderNames(); names.hasMoreElements(); ) {
+			for (Enumeration<?> names = getServletRequest().getHeaderNames(); names.hasMoreElements(); ) {
 				String headerName = (String) names.nextElement();
-				for (Enumeration<?> headerValues = this.servletRequest.getHeaders(headerName);
+				for (Enumeration<?> headerValues = getServletRequest().getHeaders(headerName);
 					 headerValues.hasMoreElements(); ) {
 					String headerValue = (String) headerValues.nextElement();
 					this.headers.add(headerName, headerValue);
@@ -98,14 +111,14 @@ public class ServletServerHttpRequest implements ServerHttpRequest {
 			// HttpServletRequest exposes some headers as properties: we should include those if not already present
 			MediaType contentType = this.headers.getContentType();
 			if (contentType == null) {
-				String requestContentType = this.servletRequest.getContentType();
+				String requestContentType = getServletRequest().getContentType();
 				if (StringUtils.hasLength(requestContentType)) {
 					contentType = MediaType.parseMediaType(requestContentType);
 					this.headers.setContentType(contentType);
 				}
 			}
 			if (contentType != null && contentType.getCharSet() == null) {
-				String requestEncoding = this.servletRequest.getCharacterEncoding();
+				String requestEncoding = getServletRequest().getCharacterEncoding();
 				if (StringUtils.hasLength(requestEncoding)) {
 					Charset charSet = Charset.forName(requestEncoding);
 					Map<String, String> params = new LinkedCaseInsensitiveMap<>();
@@ -116,7 +129,7 @@ public class ServletServerHttpRequest implements ServerHttpRequest {
 				}
 			}
 			if (this.headers.getContentLength() == -1) {
-				int requestContentLength = this.servletRequest.getContentLength();
+				int requestContentLength = getServletRequest().getContentLength();
 				if (requestContentLength != -1) {
 					this.headers.setContentLength(requestContentLength);
 				}

spring-web-reactive/src/main/java/org/springframework/http/server/reactive/ServletServerHttpResponse.java

@@ -36,6 +36,8 @@ import org.springframework.http.HttpStatus;
 import org.springframework.util.Assert;
 
 /**
+ * Adapt {@link ServerHttpResponse} to the Servlet {@link HttpServletResponse}.
+ *
  * @author Rossen Stoyanchev
  */
 public class ServletServerHttpResponse implements ServerHttpResponse {
@@ -53,20 +55,18 @@ public class ServletServerHttpResponse implements ServerHttpResponse {
 	public ServletServerHttpResponse(HttpServletResponse response, ServletAsyncContextSynchronizer synchronizer) {
 		Assert.notNull(response, "'response' must not be null");
 		this.response = response;
-		this.headers = initHttpHeaders();
+		this.headers = new ExtendedHttpHeaders(new ServletHeaderChangeListener());
 		this.subscriber = new ResponseBodySubscriber(synchronizer);
 	}
 
-	private HttpHeaders initHttpHeaders() {
-		ExtendedHttpHeaders headers = new ExtendedHttpHeaders();
-		headers.registerChangeListener(new ServletHeaderChangeListener());
-		return headers;
-	}
 
+	public HttpServletResponse getServletResponse() {
+		return this.response;
+	}
 
 	@Override
 	public void setStatusCode(HttpStatus status) {
-		this.response.setStatus(status.value());
+		getServletResponse().setStatus(status.value());
 	}
 
 	@Override
@@ -80,8 +80,11 @@ public class ServletServerHttpResponse implements ServerHttpResponse {
 
 	@Override
 	public Publisher<Void> setBody(final Publisher<ByteBuffer> publisher) {
-		return Publishers.lift(publisher, new WriteWithOperator<>(writePublisher ->
-				(s -> writePublisher.subscribe(subscriber))));
+		return Publishers.lift(publisher, new WriteWithOperator<>(this::setBodyInternal));
+	}
+
+	protected Publisher<Void> setBodyInternal(Publisher<ByteBuffer> publisher) {
+		return s -> publisher.subscribe(subscriber);
 	}
 
 
@@ -89,14 +92,14 @@ public class ServletServerHttpResponse implements ServerHttpResponse {
 
 		@Override
 		public void headerAdded(String name, String value) {
-			response.addHeader(name, value);
+			getServletResponse().addHeader(name, value);
 		}
 
 		@Override
 		public void headerPut(String key, List<String> values) {
 			// We can only add but not remove
 			for (String value : values) {
-				response.addHeader(key, value);
+				getServletResponse().addHeader(key, value);
 			}
 		}
 
@@ -106,6 +109,7 @@ public class ServletServerHttpResponse implements ServerHttpResponse {
 		}
 	}
 
+
 	private static class ResponseBodySubscriber implements WriteListener, Subscriber<ByteBuffer> {
 
 		private final ServletAsyncContextSynchronizer synchronizer;

spring-web-reactive/src/main/java/org/springframework/http/server/reactive/UndertowServerHttpRequest.java

@@ -36,12 +36,13 @@ import reactor.core.support.BackpressureUtils;
 
 import org.springframework.http.HttpHeaders;
 import org.springframework.http.HttpMethod;
-import org.springframework.http.server.reactive.ServerHttpRequest;
 import org.springframework.util.Assert;
 
 import static org.xnio.IoUtils.safeClose;
 
 /**
+ * Adapt {@link ServerHttpRequest} to the Underow {@link HttpServerExchange}.
+ *
  * @author Marek Hawrylczak
  * @author Rossen Stoyanchev
  */
@@ -49,10 +50,12 @@ public class UndertowServerHttpRequest implements ServerHttpRequest {
 
 	private final HttpServerExchange exchange;
 
-	private final Publisher<ByteBuffer> body = new RequestBodyPublisher();
+	private URI uri;
 
 	private HttpHeaders headers;
 
+	private final Publisher<ByteBuffer> body = new RequestBodyPublisher();
+
 
 	public UndertowServerHttpRequest(HttpServerExchange exchange) {
 		Assert.notNull(exchange, "'exchange' is required.");
@@ -60,31 +63,38 @@ public class UndertowServerHttpRequest implements ServerHttpRequest {
 	}
 
 
+	public HttpServerExchange getUndertowExchange() {
+		return this.exchange;
+	}
+
 	@Override
 	public HttpMethod getMethod() {
-		return HttpMethod.valueOf(this.exchange.getRequestMethod().toString());
+		return HttpMethod.valueOf(this.getUndertowExchange().getRequestMethod().toString());
 	}
 
 	@Override
 	public URI getURI() {
-		try {
-			return new URI(this.exchange.getRequestScheme(), null, this.exchange.getHostName(),
-					this.exchange.getHostPort(), this.exchange.getRequestURI(),
-					this.exchange.getQueryString(), null);
-		}
-		catch (URISyntaxException ex) {
-			throw new IllegalStateException("Could not get URI: " + ex.getMessage(), ex);
+		if (this.uri == null) {
+			try {
+				return new URI(this.getUndertowExchange().getRequestScheme(), null,
+						this.getUndertowExchange().getHostName(),
+						this.getUndertowExchange().getHostPort(),
+						this.getUndertowExchange().getRequestURI(),
+						this.getUndertowExchange().getQueryString(), null);
+			}
+			catch (URISyntaxException ex) {
+				throw new IllegalStateException("Could not get URI: " + ex.getMessage(), ex);
+			}
 		}
+		return this.uri;
 	}
 
 	@Override
 	public HttpHeaders getHeaders() {
 		if (this.headers == null) {
 			this.headers = new HttpHeaders();
-			for (HeaderValues headerValues : this.exchange.getRequestHeaders()) {
-				for (String value : headerValues) {
-					this.headers.add(headerValues.getHeaderName().toString(), value);
-				}
+			for (HeaderValues values : this.getUndertowExchange().getRequestHeaders()) {
+				this.headers.put(values.getHeaderName().toString(), values);
 			}
 		}
 		return this.headers;

spring-web-reactive/src/main/java/org/springframework/http/server/reactive/UndertowServerHttpResponse.java

@@ -46,6 +46,8 @@ import static org.xnio.ChannelListeners.flushingChannelListener;
 import static org.xnio.IoUtils.safeClose;
 
 /**
+ * Adapt {@link ServerHttpResponse} to the Undertow {@link HttpServerExchange}.
+ *
  * @author Marek Hawrylczak
  * @author Rossen Stoyanchev
  */
@@ -56,28 +58,26 @@ public class UndertowServerHttpResponse implements ServerHttpResponse {
 
 	private final HttpServerExchange exchange;
 
-	private final ResponseBodySubscriber bodySubscriber = new ResponseBodySubscriber();
-
 	private final HttpHeaders headers;
 
+	private final ResponseBodySubscriber bodySubscriber = new ResponseBodySubscriber();
+
 
 	public UndertowServerHttpResponse(HttpServerExchange exchange) {
 		Assert.notNull(exchange, "'exchange' is required.");
 		this.exchange = exchange;
-		this.headers = initHttpHeaders();
+		this.headers = new ExtendedHttpHeaders(new UndertowHeaderChangeListener());
 	}
 
-	private HttpHeaders initHttpHeaders() {
-		ExtendedHttpHeaders headers = new ExtendedHttpHeaders();
-		headers.registerChangeListener(new UndertowHeaderChangeListener());
-		return headers;
-	}
 
+	public HttpServerExchange getUndertowExchange() {
+		return this.exchange;
+	}
 
 	@Override
 	public void setStatusCode(HttpStatus status) {
 		Assert.notNull(status);
-		this.exchange.setStatusCode(status.value());
+		getUndertowExchange().setStatusCode(status.value());
 	}
 
 	@Override
@@ -87,8 +87,11 @@ public class UndertowServerHttpResponse implements ServerHttpResponse {
 
 	@Override
 	public Publisher<Void> setBody(Publisher<ByteBuffer> publisher) {
-		return Publishers.lift(publisher, new WriteWithOperator<>(writePublisher ->
-				(subscriber -> writePublisher.subscribe(bodySubscriber))));
+		return Publishers.lift(publisher, new WriteWithOperator<>(this::setBodyInternal));
+	}
+
+	protected Publisher<Void> setBodyInternal(Publisher<ByteBuffer> writePublisher) {
+		return subscriber -> writePublisher.subscribe(bodySubscriber);
 	}
 
 
@@ -96,17 +99,19 @@ public class UndertowServerHttpResponse implements ServerHttpResponse {
 
 		@Override
 		public void headerAdded(String name, String value) {
-			exchange.getResponseHeaders().add(HttpString.tryFromString(name), value);
+			HttpString headerName = HttpString.tryFromString(name);
+			getUndertowExchange().getResponseHeaders().add(headerName, value);
 		}
 
 		@Override
 		public void headerPut(String key, List<String> values) {
-			exchange.getResponseHeaders().putAll(HttpString.tryFromString(key), values);
+			HttpString headerName = HttpString.tryFromString(key);
+			getUndertowExchange().getResponseHeaders().putAll(headerName, values);
 		}
 
 		@Override
 		public void headerRemoved(String key) {
-			exchange.getResponseHeaders().remove(key);
+			getUndertowExchange().getResponseHeaders().remove(key);
 		}
 	}