HttpClient based ClientHttpRequestFactory

As JDK17 is now the baseline it is possible to use the
HttpClient provided by Java.

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

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+/*
+ * Copyright 2023-2023 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;
+
+import java.io.IOException;
+import java.io.InputStream;
+import java.net.URI;
+import java.net.http.HttpClient;
+import java.net.http.HttpRequest;
+import java.net.http.HttpResponse;
+import java.util.List;
+
+import org.springframework.http.HttpHeaders;
+import org.springframework.http.HttpMethod;
+
+/**
+ * {@link ClientHttpRequest} implementation based on the Java {@code HttpClient}.
+ *
+ * @author Marten Deinum
+ * @since 6.1
+ */
+public class JdkClientClientHttpRequest extends AbstractBufferingClientHttpRequest {
+
+	/*
+	 * The JDK HttpRequest doesn't allow all headers to be set. The named headers are taken from the default
+	 * implementation for HttpRequest.
+	 */
+	private static final List<String> DISALLOWED_HEADERS =
+			List.of("connection", "content-length", "expect", "host", "upgrade");
+
+	private final HttpClient client;
+	private final URI uri;
+	private final HttpMethod method;
+	public JdkClientClientHttpRequest(HttpClient client, URI uri, HttpMethod method) {
+		this.client = client;
+		this.uri = uri;
+		this.method = method;
+	}
+
+	@Override
+	public HttpMethod getMethod() {
+		return this.method;
+	}
+
+	@Override
+	public URI getURI() {
+		return this.uri;
+	}
+
+	@Override
+	protected ClientHttpResponse executeInternal(HttpHeaders headers, byte[] content) throws IOException {
+
+		HttpRequest.Builder builder = HttpRequest.newBuilder(this.uri)
+				.method(getMethod().name(), HttpRequest.BodyPublishers.ofByteArray(content));
+
+		addHeaders(headers, builder);
+		HttpRequest request = builder.build();
+		HttpResponse<InputStream> response;
+		try {
+			response = this.client.send(request, HttpResponse.BodyHandlers.ofInputStream());
+		} catch (InterruptedException ex)
+		{
+			Thread.currentThread().interrupt();
+			throw new IllegalStateException("Request interupted.", ex);
+		}
+		return new JdkClientClientHttpResponse(response);
+	}
+
+	private static void addHeaders(HttpHeaders headers, HttpRequest.Builder builder) {
+		headers.forEach((headerName, headerValues) -> {
+			if (!DISALLOWED_HEADERS.contains(headerName.toLowerCase())) {
+				for (String headerValue : headerValues) {
+					builder.header(headerName, headerValue);
+				}
+			}
+		});
+	}
+}

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

@@ -0,0 +1,55 @@
+/*
+ * Copyright 2023-2023 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;
+
+import java.io.IOException;
+import java.net.URI;
+import java.net.http.HttpClient;
+
+import org.springframework.http.HttpMethod;
+
+
+/**
+ * {@link ClientHttpRequestFactory} implementation that uses a
+ * <a href="https://docs.oracle.com/en/java/javase/17/docs/api/java.net.http/java/net/http/HttpClient.html">HttpClient</a> to create requests.
+ *
+ * @author Marten Deinum
+ * @since 6.1
+ */
+public class JdkClientClientHttpRequestFactory implements ClientHttpRequestFactory {
+
+	private HttpClient client;
+
+	private final boolean defaultClient;
+
+
+	public JdkClientClientHttpRequestFactory() {
+		this.client = HttpClient.newHttpClient();
+		this.defaultClient = true;
+	}
+
+	public JdkClientClientHttpRequestFactory(HttpClient client) {
+		this.client = client;
+		this.defaultClient = false;
+	}
+
+	@Override
+	public ClientHttpRequest createRequest(URI uri, HttpMethod httpMethod) throws IOException {
+		return new JdkClientClientHttpRequest(this.client, uri, httpMethod);
+	}
+
+}

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

@@ -0,0 +1,98 @@
+/*
+ * Copyright 2023-2023 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;
+
+import java.io.IOException;
+import java.io.InputStream;
+import java.net.http.HttpResponse;
+
+import org.springframework.http.HttpHeaders;
+import org.springframework.http.HttpStatus;
+import org.springframework.http.HttpStatusCode;
+import org.springframework.lang.Nullable;
+import org.springframework.util.StreamUtils;
+
+/**
+ * {@link ClientHttpResponse} implementation based on the Java {@code HttpClient}.
+ *
+ * @author Marten Deinum
+ * @since 6.1
+ */
+public class JdkClientClientHttpResponse implements ClientHttpResponse {
+
+	private final HttpResponse<InputStream> response;
+	@Nullable
+	private volatile HttpHeaders headers;
+
+	public JdkClientClientHttpResponse(HttpResponse<InputStream> response) {
+		this.response = response;
+	}
+
+	@Override
+	public HttpStatusCode getStatusCode() throws IOException {
+		return HttpStatusCode.valueOf(this.response.statusCode());
+	}
+
+	@Override
+	@Deprecated
+	public int getRawStatusCode() {
+		return this.response.statusCode();
+	}
+
+	@Override
+	public String getStatusText() {
+		HttpStatus status = HttpStatus.resolve(this.response.statusCode());
+		return (status != null) ? status.getReasonPhrase() : "";
+	}
+
+	@Override
+	public InputStream getBody() throws IOException {
+		InputStream body = this.response.body();
+		return (body != null ? body : InputStream.nullInputStream());
+	}
+
+	@Override
+	public HttpHeaders getHeaders() {
+		HttpHeaders headers = this.headers;
+		if (headers == null) {
+			headers = new HttpHeaders();
+			for (String headerName : this.response.headers().map().keySet()) {
+				for (String headerValue : this.response.headers().allValues(headerName)) {
+					headers.add(headerName, headerValue);
+				}
+			}
+			this.headers = headers;
+		}
+		return headers;
+	}
+
+	@Override
+	public void close() {
+		InputStream body = this.response.body();
+		try {
+			try {
+				StreamUtils.drain(body);
+			}
+			finally {
+				body.close();
+			}
+		}
+		catch (IOException ex) {
+			// Ignore exception on close...
+		}
+	}
+}

spring-web/src/test/java/org/springframework/http/client/JdkClientClientHttpRequestFactoryTests.java

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+/*
+ * Copyright 2023-2023 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;
+
+import org.junit.jupiter.api.Test;
+
+import org.springframework.http.HttpMethod;
+
+/**
+ * @author Marten Deinum
+ */
+public class JdkClientClientHttpRequestFactoryTests extends AbstractHttpRequestFactoryTests {
+
+	@Override
+	protected ClientHttpRequestFactory createRequestFactory() {
+		return new JdkClientClientHttpRequestFactory();
+	}
+
+	@Override
+	@Test
+	public void httpMethods() throws Exception {
+		super.httpMethods();
+		assertHttpMethod("patch", HttpMethod.PATCH);
+	}
+
+}