Support Jetty 10 in JettyClientHttpRequest

Though Jetty 10 was previously supported in the JettyClientHttpResponse,
this commit ensures support in the JettyClientHttpRequest.

Closes gh-29867
See gh-26123

Author: poutsma

spring-web/src/main/java/org/springframework/http/client/reactive/Jetty10HttpFieldsHelper.java

@@ -0,0 +1,93 @@
+/*
+ * Copyright 2002-2023 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.
+ * You may obtain a copy of the License at
+ *
+ *      https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.springframework.http.client.reactive;
+
+import java.lang.reflect.Method;
+
+import org.eclipse.jetty.client.api.Request;
+import org.eclipse.jetty.client.api.Response;
+
+import org.springframework.http.HttpHeaders;
+import org.springframework.lang.Nullable;
+import org.springframework.util.Assert;
+import org.springframework.util.ReflectionUtils;
+
+/**
+ * Used to support Jetty 10.
+ *
+ * @author Rossen Stoyanchev
+ * @author Arjen Poutsma
+ * @since 5.3.26
+ */
+abstract class Jetty10HttpFieldsHelper {
+
+	private static final boolean jetty10Present;
+
+	private static final Method requestGetHeadersMethod;
+
+	private static final Method responseGetHeadersMethod;
+
+	private static final Method getNameMethod;
+
+	private static final Method getValueMethod;
+
+
+	static {
+		try {
+			ClassLoader classLoader = JettyClientHttpResponse.class.getClassLoader();
+			Class<?> httpFieldsClass = classLoader.loadClass("org.eclipse.jetty.http.HttpFields");
+			jetty10Present = httpFieldsClass.isInterface();
+			requestGetHeadersMethod = Request.class.getMethod("getHeaders");
+			responseGetHeadersMethod = Response.class.getMethod("getHeaders");
+			Class<?> httpFieldClass = classLoader.loadClass("org.eclipse.jetty.http.HttpField");
+			getNameMethod = httpFieldClass.getMethod("getName");
+			getValueMethod = httpFieldClass.getMethod("getValue");
+		}
+		catch (ClassNotFoundException | NoSuchMethodException ex) {
+			throw new IllegalStateException("No compatible Jetty version found", ex);
+		}
+	}
+
+
+	public static boolean jetty10Present() {
+		return jetty10Present;
+	}
+
+	public static HttpHeaders getHttpHeaders(Request request) {
+		Iterable<?> iterator = (Iterable<?>)
+				ReflectionUtils.invokeMethod(requestGetHeadersMethod, request);
+		return getHttpHeadersInternal(iterator);
+	}
+
+	public static HttpHeaders getHttpHeaders(Response response) {
+		Iterable<?> iterator = (Iterable<?>)
+				ReflectionUtils.invokeMethod(responseGetHeadersMethod, response);
+		return getHttpHeadersInternal(iterator);
+	}
+
+	private static HttpHeaders getHttpHeadersInternal(@Nullable Iterable<?> iterator) {
+		Assert.notNull(iterator, "Iterator must not be null");
+		HttpHeaders headers = new HttpHeaders();
+		for (Object field : iterator) {
+			String name = (String) ReflectionUtils.invokeMethod(getNameMethod, field);
+			Assert.notNull(name, "Header name must not be null");
+			String value = (String) ReflectionUtils.invokeMethod(getValueMethod, field);
+			headers.add(name, value);
+		}
+		return headers;
+	}
+}

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

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2022 the original author or authors.
+ * Copyright 2002-2023 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.
@@ -37,6 +37,7 @@
 import org.springframework.http.HttpHeaders;
 import org.springframework.http.HttpMethod;
 import org.springframework.http.MediaType;
+import org.springframework.util.MultiValueMap;
 
 /**
  * {@link ClientHttpRequest} implementation for the Jetty ReactiveStreams HTTP client.
@@ -54,7 +55,6 @@ class JettyClientHttpRequest extends AbstractClientHttpRequest {
 	private final ReactiveRequest.Builder builder;
 
 
-
 	public JettyClientHttpRequest(Request jettyRequest, DataBufferFactory bufferFactory) {
 		this.jettyRequest = jettyRequest;
 		this.bufferFactory = bufferFactory;
@@ -144,7 +144,11 @@ protected void applyHeaders() {
 
 	@Override
 	protected HttpHeaders initReadOnlyHeaders() {
-		return HttpHeaders.readOnlyHttpHeaders(new JettyHeadersAdapter(this.jettyRequest.getHeaders()));
+		MultiValueMap<String, String> headers = (Jetty10HttpFieldsHelper.jetty10Present() ?
+				Jetty10HttpFieldsHelper.getHttpHeaders(this.jettyRequest) :
+				new JettyHeadersAdapter(this.jettyRequest.getHeaders()));
+
+		return HttpHeaders.readOnlyHttpHeaders(headers);
 	}
 
 	public ReactiveRequest toReactiveRequest() {

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

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2021 the original author or authors.
+ * Copyright 2002-2023 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.
@@ -16,13 +16,11 @@
 
 package org.springframework.http.client.reactive;
 
-import java.lang.reflect.Method;
 import java.net.HttpCookie;
 import java.util.List;
 import java.util.regex.Matcher;
 import java.util.regex.Pattern;
 
-import org.eclipse.jetty.client.api.Response;
 import org.eclipse.jetty.reactive.client.ReactiveResponse;
 import org.reactivestreams.Publisher;
 import reactor.core.publisher.Flux;
@@ -32,11 +30,9 @@
 import org.springframework.http.HttpStatus;
 import org.springframework.http.ResponseCookie;
 import org.springframework.lang.Nullable;
-import org.springframework.util.Assert;
 import org.springframework.util.CollectionUtils;
 import org.springframework.util.LinkedMultiValueMap;
 import org.springframework.util.MultiValueMap;
-import org.springframework.util.ReflectionUtils;
 
 /**
  * {@link ClientHttpResponse} implementation for the Jetty ReactiveStreams HTTP client.
@@ -50,10 +46,6 @@ class JettyClientHttpResponse implements ClientHttpResponse {
 
 	private static final Pattern SAMESITE_PATTERN = Pattern.compile("(?i).*SameSite=(Strict|Lax|None).*");
 
-	private static final ClassLoader classLoader = JettyClientHttpResponse.class.getClassLoader();
-
-	private static final boolean jetty10Present;
-
 
 	private final ReactiveResponse reactiveResponse;
 
@@ -62,23 +54,12 @@ class JettyClientHttpResponse implements ClientHttpResponse {
 	private final HttpHeaders headers;
 
 
-	static {
-		try {
-			Class<?> httpFieldsClass = classLoader.loadClass("org.eclipse.jetty.http.HttpFields");
-			jetty10Present = httpFieldsClass.isInterface();
-		}
-		catch (ClassNotFoundException ex) {
-			throw new IllegalStateException("No compatible Jetty version found", ex);
-		}
-	}
-
-
 	public JettyClientHttpResponse(ReactiveResponse reactiveResponse, Publisher<DataBuffer> content) {
 		this.reactiveResponse = reactiveResponse;
 		this.content = Flux.from(content);
 
-		MultiValueMap<String, String> headers = (jetty10Present ?
-				Jetty10HttpFieldsHelper.getHttpHeaders(reactiveResponse) :
+		MultiValueMap<String, String> headers = (Jetty10HttpFieldsHelper.jetty10Present() ?
+				Jetty10HttpFieldsHelper.getHttpHeaders(reactiveResponse.getResponse()) :
 				new JettyHeadersAdapter(reactiveResponse.getHeaders()));
 
 		this.headers = HttpHeaders.readOnlyHttpHeaders(headers);
@@ -132,40 +113,4 @@ public HttpHeaders getHeaders() {
 		return this.headers;
 	}
 
-
-	private static class Jetty10HttpFieldsHelper {
-
-		private static final Method getHeadersMethod;
-
-		private static final Method getNameMethod;
-
-		private static final Method getValueMethod;
-
-		static {
-			try {
-				getHeadersMethod = Response.class.getMethod("getHeaders");
-				Class<?> type = classLoader.loadClass("org.eclipse.jetty.http.HttpField");
-				getNameMethod = type.getMethod("getName");
-				getValueMethod = type.getMethod("getValue");
-			}
-			catch (ClassNotFoundException | NoSuchMethodException ex) {
-				throw new IllegalStateException("No compatible Jetty version found", ex);
-			}
-		}
-
-		public static HttpHeaders getHttpHeaders(ReactiveResponse response) {
-			HttpHeaders headers = new HttpHeaders();
-			Iterable<?> iterator = (Iterable<?>)
-					ReflectionUtils.invokeMethod(getHeadersMethod, response.getResponse());
-			Assert.notNull(iterator, "Iterator must not be null");
-			for (Object field : iterator) {
-				String name = (String) ReflectionUtils.invokeMethod(getNameMethod, field);
-				Assert.notNull(name, "Header name must not be null");
-				String value = (String) ReflectionUtils.invokeMethod(getValueMethod, field);
-				headers.add(name, value);
-			}
-			return headers;
-		}
-	}
-
 }