Merge branch '7.0.x'

spring-test/src/main/java/org/springframework/test/web/client/MockRestServiceServer.java

@@ -33,9 +33,9 @@ import org.springframework.web.client.support.RestGatewaySupport;
 
 /**
  * <strong>Main entry point for client-side REST testing</strong>. Used for tests
- * that involve direct or indirect use of the {@link RestTemplate}. Provides a
+ * that involve direct or indirect use of the {@link RestClient}. Provides a
  * way to set up expected requests that will be performed through the
- * {@code RestTemplate} as well as mock responses to send back thus removing the
+ * {@code RestClient} as well as mock responses to send back thus removing the
  * need for an actual server.
  *
  * <p>Below is an example that assumes static imports from
@@ -43,13 +43,14 @@ import org.springframework.web.client.support.RestGatewaySupport;
  * and {@code ExpectedCount}:
  *
  * <pre class="code">
- * RestTemplate restTemplate = new RestTemplate()
- * MockRestServiceServer server = MockRestServiceServer.bindTo(restTemplate).build();
+ * RestClient.Builder clientBuilder = RestClient.builder();
+ * MockRestServiceServer server = MockRestServiceServer.bindTo(clientBuilder).build();
+ * RestClient restClient = clientBuilder.build();
  *
  * server.expect(manyTimes(), requestTo("/hotels/42")).andExpect(method(HttpMethod.GET))
  *     .andRespond(withSuccess("{ \"id\" : \"42\", \"name\" : \"Holiday Inn\"}", MediaType.APPLICATION_JSON));
  *
- * Hotel hotel = restTemplate.getForObject("/hotels/{id}", Hotel.class, 42);
+ * Hotel hotel = restClient.get().uri("/hotels/{id}", 42).retrieve().body(Hotel.class);
  * &#47;&#47; Use the hotel instance...
  *
  * // Verify all expectations met
@@ -167,6 +168,16 @@ public final class MockRestServiceServer {
 	}
 
 
+	/**
+	 * A shortcut for {@code bindTo(clientBuilder).build()}.
+	 * @param clientBuilder the RestClient builder to set up for mock testing
+	 * @return the mock server
+	 * @since 7.0.7
+	 */
+	public static MockRestServiceServer createServer(RestClient.Builder clientBuilder) {
+		return bindTo(clientBuilder).build();
+	}
+
 	/**
 	 * A shortcut for {@code bindTo(restTemplate).build()}.
 	 * @param restTemplate the RestTemplate to set up for mock testing

spring-test/src/main/java/org/springframework/test/web/client/response/ExecutingResponseCreator.java

@@ -32,12 +32,13 @@ import org.springframework.util.StreamUtils;
  * {@code ResponseCreator} that obtains the response by executing the request
  * through a {@link ClientHttpRequestFactory}. This is useful in scenarios with
  * multiple remote services where some need to be called rather than mocked.
- * <p>The {@code ClientHttpRequestFactory} is typically obtained from the
- * {@code RestTemplate} before it is passed to {@code MockRestServiceServer},
+ * <p>The {@code ClientHttpRequestFactory} is typically used for building the
+ * {@code RestClient} and is passed to {@code MockRestServiceServer},
  * in effect using the original factory rather than the test factory:
  * <pre><code>
- * ResponseCreator withActualResponse = new ExecutingResponseCreator(restTemplate);
- * MockRestServiceServer server = MockRestServiceServer.bindTo(restTemplate).build();
+ * RestClient.Builder restClientBuilder = RestClient.builder().requestFactory(requestFactory);
+ * ResponseCreator withActualResponse = new ExecutingResponseCreator(requestFactory);
+ * MockRestServiceServer server = MockRestServiceServer.bindTo(restClientBuilder).build();
  * //...
  * server.expect(requestTo("/foo")).andRespond(withSuccess());
  * server.expect(requestTo("/bar")).andRespond(withActualResponse);

spring-test/src/test/java/org/springframework/test/web/client/MockRestServiceServerTests.java

@@ -30,7 +30,7 @@ import org.springframework.mock.http.client.MockClientHttpRequest;
 import org.springframework.mock.http.client.MockClientHttpResponse;
 import org.springframework.test.web.client.MockRestServiceServer.MockRestServiceServerBuilder;
 import org.springframework.test.web.client.response.ExecutingResponseCreator;
-import org.springframework.web.client.RestTemplate;
+import org.springframework.web.client.RestClient;
 
 import static org.assertj.core.api.Assertions.assertThat;
 import static org.assertj.core.api.Assertions.assertThatExceptionOfType;
@@ -49,65 +49,72 @@ import static org.springframework.test.web.client.response.MockRestResponseCreat
  */
 class MockRestServiceServerTests {
 
-	private final RestTemplate restTemplate = new RestTemplate();
+	private final RestClient.Builder clientBuilder = RestClient.builder();
 
 
 	@Test
 	void buildMultipleTimes() {
-		MockRestServiceServerBuilder builder = MockRestServiceServer.bindTo(this.restTemplate);
+		MockRestServiceServerBuilder builder = MockRestServiceServer.bindTo(this.clientBuilder);
 
 		MockRestServiceServer server = builder.build();
+		RestClient restClient = this.clientBuilder.build();
 		server.expect(requestTo("/foo")).andRespond(withSuccess());
-		this.restTemplate.getForObject("/foo", Void.class);
+		restClient.get().uri("/foo").retrieve().toBodilessEntity();
 		server.verify();
 
 		server = builder.ignoreExpectOrder(true).build();
+		restClient = this.clientBuilder.build();
 		server.expect(requestTo("/foo")).andRespond(withSuccess());
 		server.expect(requestTo("/bar")).andRespond(withSuccess());
-		this.restTemplate.getForObject("/bar", Void.class);
-		this.restTemplate.getForObject("/foo", Void.class);
+		restClient.get().uri("/bar").retrieve().toBodilessEntity();
+		restClient.get().uri("/foo").retrieve().toBodilessEntity();
 		server.verify();
 
 		server = builder.build();
+		restClient = this.clientBuilder.build();
 		server.expect(requestTo("/bar")).andRespond(withSuccess());
-		this.restTemplate.getForObject("/bar", Void.class);
+		restClient.get().uri("/bar").retrieve().toBodilessEntity();
 		server.verify();
 	}
 
 	@Test
 	void exactExpectOrder() {
-		MockRestServiceServer server = MockRestServiceServer.bindTo(this.restTemplate)
+		MockRestServiceServer server = MockRestServiceServer.bindTo(this.clientBuilder)
 				.ignoreExpectOrder(false).build();
+		RestClient restClient = this.clientBuilder.build();
 
 		server.expect(requestTo("/foo")).andRespond(withSuccess());
 		server.expect(requestTo("/bar")).andRespond(withSuccess());
 		assertThatExceptionOfType(AssertionError.class).isThrownBy(() ->
-				this.restTemplate.getForObject("/bar", Void.class));
+				restClient.get().uri("/bar").retrieve().toBodilessEntity());
 	}
 
 	@Test
 	void ignoreExpectOrder() {
-		MockRestServiceServer server = MockRestServiceServer.bindTo(this.restTemplate)
+		MockRestServiceServer server = MockRestServiceServer.bindTo(this.clientBuilder)
 				.ignoreExpectOrder(true).build();
+		RestClient restClient = this.clientBuilder.build();
 
 		server.expect(requestTo("/foo")).andRespond(withSuccess());
 		server.expect(requestTo("/bar")).andRespond(withSuccess());
-		this.restTemplate.getForObject("/bar", Void.class);
-		this.restTemplate.getForObject("/foo", Void.class);
+		restClient.get().uri("/bar").retrieve().toBodilessEntity();
+		restClient.get().uri("/foo").retrieve().toBodilessEntity();
 		server.verify();
 	}
 
 	@Test
 	void executingResponseCreator() {
-		RestTemplate restTemplate = createEchoRestTemplate();
-		ExecutingResponseCreator withActualCall = new ExecutingResponseCreator(restTemplate.getRequestFactory());
+		ClientHttpRequestFactory clientRequestFactory = createEchoClientRequestFactory();
+		ExecutingResponseCreator withActualCall = new ExecutingResponseCreator(clientRequestFactory);
+		this.clientBuilder.requestFactory(clientRequestFactory);
+		MockRestServiceServer server = MockRestServiceServer.bindTo(this.clientBuilder).build();
+		RestClient restClient = this.clientBuilder.build();
 
-		MockRestServiceServer server = MockRestServiceServer.bindTo(restTemplate).build();
 		server.expect(requestTo("/profile")).andRespond(withSuccess());
 		server.expect(requestTo("/quoteOfTheDay")).andRespond(withActualCall);
 
-		var response1 = restTemplate.getForEntity("/profile", String.class);
-		var response2 = restTemplate.getForEntity("/quoteOfTheDay", String.class);
+		var response1 = restClient.get().uri("/profile").retrieve().toEntity(String.class);
+		var response2 = restClient.get().uri("/quoteOfTheDay").retrieve().toEntity(String.class);
 		server.verify();
 
 		assertThat(response1.getStatusCode().value()).isEqualTo(200);
@@ -116,8 +123,8 @@ class MockRestServiceServerTests {
 		assertThat(response2.getBody()).isEqualTo("echo from /quoteOfTheDay");
 	}
 
-	private static RestTemplate createEchoRestTemplate() {
-		ClientHttpRequestFactory requestFactory = (uri, httpMethod) -> {
+	private static ClientHttpRequestFactory createEchoClientRequestFactory() {
+		return (uri, httpMethod) -> {
 			MockClientHttpRequest request = new MockClientHttpRequest(httpMethod, uri);
 			ClientHttpResponse response = new MockClientHttpResponse(
 					("echo from " + uri.getPath()).getBytes(StandardCharsets.UTF_8),
@@ -126,61 +133,64 @@ class MockRestServiceServerTests {
 			request.setResponse(response);
 			return request;
 		};
-		return new RestTemplate(requestFactory);
 	}
 
 	@Test
 	void resetAndReuseServer() {
-		MockRestServiceServer server = MockRestServiceServer.bindTo(this.restTemplate).build();
+		MockRestServiceServer server = MockRestServiceServer.bindTo(this.clientBuilder).build();
+		RestClient restClient = this.clientBuilder.build();
 
 		server.expect(requestTo("/foo")).andRespond(withSuccess());
-		this.restTemplate.getForObject("/foo", Void.class);
+		restClient.get().uri("/foo").retrieve().toBodilessEntity();
 		server.verify();
 		server.reset();
 
 		server.expect(requestTo("/bar")).andRespond(withSuccess());
-		this.restTemplate.getForObject("/bar", Void.class);
+		restClient.get().uri("/bar").retrieve().toBodilessEntity();
 		server.verify();
 	}
 
 	@Test
 	void resetAndReuseServerWithUnorderedExpectationManager() {
-		MockRestServiceServer server = MockRestServiceServer.bindTo(this.restTemplate)
+		MockRestServiceServer server = MockRestServiceServer.bindTo(this.clientBuilder)
 				.ignoreExpectOrder(true).build();
+		RestClient restClient = this.clientBuilder.build();
 
 		server.expect(requestTo("/foo")).andRespond(withSuccess());
-		this.restTemplate.getForObject("/foo", Void.class);
+		restClient.get().uri("/foo").retrieve().toBodilessEntity();
 		server.verify();
 		server.reset();
 
 		server.expect(requestTo("/foo")).andRespond(withSuccess());
 		server.expect(requestTo("/bar")).andRespond(withSuccess());
-		this.restTemplate.getForObject("/bar", Void.class);
-		this.restTemplate.getForObject("/foo", Void.class);
+		restClient.get().uri("/bar").retrieve().toBodilessEntity();
+		restClient.get().uri("/foo").retrieve().toBodilessEntity();
 		server.verify();
 	}
 
 	@Test  // gh-24486
 	void resetClearsRequestFailures() {
-		MockRestServiceServer server = MockRestServiceServer.bindTo(this.restTemplate).build();
+		MockRestServiceServer server = MockRestServiceServer.bindTo(this.clientBuilder).build();
+		RestClient restClient = this.clientBuilder.build();
 		server.expect(once(), requestTo("/remoteurl")).andRespond(withSuccess());
-		this.restTemplate.postForEntity("/remoteurl", null, String.class);
+		restClient.post().uri("/remoteurl").retrieve().body(String.class);
 		server.verify();
 
 		assertThatExceptionOfType(AssertionError.class)
-				.isThrownBy(() -> this.restTemplate.postForEntity("/remoteurl", null, String.class))
+				.isThrownBy(() -> restClient.post().uri("/remoteurl").retrieve().body(String.class))
 				.withMessageStartingWith("No further requests expected");
 
 		server.reset();
 
 		server.expect(once(), requestTo("/remoteurl")).andRespond(withSuccess());
-		this.restTemplate.postForEntity("/remoteurl", null, String.class);
+		restClient.post().uri("/remoteurl").retrieve().body(String.class);
 		server.verify();
 	}
 
 	@Test  // SPR-16132
 	void followUpRequestAfterFailure() {
-		MockRestServiceServer server = MockRestServiceServer.bindTo(this.restTemplate).build();
+		MockRestServiceServer server = MockRestServiceServer.bindTo(this.clientBuilder).build();
+		RestClient restClient = this.clientBuilder.build();
 
 		server.expect(requestTo("/some-service/some-endpoint"))
 				.andRespond(request -> { throw new SocketException("pseudo network error"); });
@@ -189,11 +199,11 @@ class MockRestServiceServerTests {
 				.andExpect(method(POST)).andRespond(withSuccess());
 
 		try {
-			this.restTemplate.getForEntity("/some-service/some-endpoint", String.class);
+			restClient.get().uri("/some-service/some-endpoint").retrieve().body(String.class);
 			fail("Expected exception");
 		}
 		catch (Exception ex) {
-			this.restTemplate.postForEntity("/reporting-service/report-error", ex.toString(), String.class);
+			restClient.post().uri("/reporting-service/report-error").retrieve().body(String.class);
 		}
 
 		server.verify();
@@ -201,12 +211,13 @@ class MockRestServiceServerTests {
 
 	@Test  // gh-21799
 	void verifyShouldFailIfRequestsFailed() {
-		MockRestServiceServer server = MockRestServiceServer.bindTo(this.restTemplate).build();
+		MockRestServiceServer server = MockRestServiceServer.bindTo(this.clientBuilder).build();
 		server.expect(once(), requestTo("/remoteurl")).andRespond(withSuccess());
+		RestClient restClient = this.clientBuilder.build();
 
-		this.restTemplate.postForEntity("/remoteurl", null, String.class);
+		restClient.post().uri("/remoteurl").retrieve().body(String.class);
 		assertThatExceptionOfType(AssertionError.class)
-				.isThrownBy(() -> this.restTemplate.postForEntity("/remoteurl", null, String.class))
+				.isThrownBy(() -> restClient.post().uri("/remoteurl").retrieve().body(String.class))
 				.withMessageStartingWith("No further requests expected");
 
 		assertThatExceptionOfType(AssertionError.class)
@@ -216,24 +227,26 @@ class MockRestServiceServerTests {
 
 	@Test
 	void verifyWithTimeout() {
-		MockRestServiceServerBuilder builder = MockRestServiceServer.bindTo(this.restTemplate);
+		MockRestServiceServerBuilder builder = MockRestServiceServer.bindTo(this.clientBuilder);
 
 		MockRestServiceServer server1 = builder.build();
+		RestClient restClient = this.clientBuilder.build();
 		server1.expect(requestTo("/foo")).andRespond(withSuccess());
 		server1.expect(requestTo("/bar")).andRespond(withSuccess());
-		this.restTemplate.getForObject("/foo", Void.class);
+		restClient.get().uri("/foo").retrieve().toBodilessEntity();
 
 		assertThatThrownBy(() -> server1.verify(Duration.ofMillis(100))).hasMessage("""
 				Further request(s) expected leaving 1 unsatisfied expectation(s).
 				1 request(s) executed:
-				GET /foo, headers: [Accept:"application/json, application/*+json"]
+				GET /foo
 				""");
 
 		MockRestServiceServer server2 = builder.build();
+		restClient = this.clientBuilder.build();
 		server2.expect(requestTo("/foo")).andRespond(withSuccess());
 		server2.expect(requestTo("/bar")).andRespond(withSuccess());
-		this.restTemplate.getForObject("/foo", Void.class);
-		this.restTemplate.getForObject("/bar", Void.class);
+		restClient.get().uri("/foo").retrieve().toBodilessEntity();
+		restClient.get().uri("/bar").retrieve().toBodilessEntity();
 
 		server2.verify(Duration.ofMillis(100));
 	}

spring-test/src/test/java/org/springframework/test/web/client/samples/SampleTests.java

@@ -17,8 +17,8 @@
 package org.springframework.test.web.client.samples;
 
 import java.io.IOException;
-import java.util.Collections;
 
+import org.junit.jupiter.api.BeforeEach;
 import org.junit.jupiter.api.Test;
 
 import org.springframework.core.io.ClassPathResource;
@@ -32,7 +32,7 @@ import org.springframework.http.client.ClientHttpResponse;
 import org.springframework.test.web.Person;
 import org.springframework.test.web.client.MockRestServiceServer;
 import org.springframework.util.FileCopyUtils;
-import org.springframework.web.client.RestTemplate;
+import org.springframework.web.client.RestClient;
 
 import static org.assertj.core.api.Assertions.assertThat;
 import static org.assertj.core.api.Assertions.assertThatExceptionOfType;
@@ -46,17 +46,24 @@ import static org.springframework.test.web.client.response.MockRestResponseCreat
 /**
  * Examples to demonstrate writing client-side REST tests with Spring MVC Test.
  *
- * <p>While the tests in this class invoke the RestTemplate directly, in actual
- * tests the RestTemplate may likely be invoked indirectly, i.e. through client
+ * <p>While the tests in this class invoke the RestClient directly, in actual
+ * tests the RestClient may likely be invoked indirectly, i.e. through client
  * code.
  *
  * @author Rossen Stoyanchev
  */
 class SampleTests {
 
-	private final RestTemplate restTemplate = new RestTemplate();
+	private RestClient restClient;
 
-	private final MockRestServiceServer mockServer = MockRestServiceServer.bindTo(this.restTemplate).ignoreExpectOrder(true).build();
+	private MockRestServiceServer mockServer;
+
+	@BeforeEach
+	void setup() {
+		RestClient.Builder clientBuilder = RestClient.builder();
+		this.mockServer = MockRestServiceServer.bindTo(clientBuilder).ignoreExpectOrder(true).build();
+		this.restClient = clientBuilder.build();
+	}
 
 
 	@Test
@@ -67,7 +74,7 @@ class SampleTests {
 			.andRespond(withSuccess(responseBody, MediaType.APPLICATION_JSON));
 
 		@SuppressWarnings("unused")
-		Person ludwig = this.restTemplate.getForObject("/composers/{id}", Person.class, 42);
+		Person ludwig = this.restClient.get().uri("/composers/{id}", 42).retrieve().body(Person.class);
 
 		// We are only validating the request. The response is mocked out.
 		// hotel.getId() == 42
@@ -84,15 +91,15 @@ class SampleTests {
 				.andRespond(withSuccess(responseBody, MediaType.APPLICATION_JSON));
 
 		@SuppressWarnings("unused")
-		Person ludwig = this.restTemplate.getForObject("/composers/{id}", Person.class, 42);
+		Person ludwig = this.restClient.get().uri("/composers/{id}", 42).retrieve().body(Person.class);
 
 		// We are only validating the request. The response is mocked out.
 		// hotel.getId() == 42
 		// hotel.getName().equals("Holiday Inn")
 
-		this.restTemplate.getForObject("/composers/{id}", Person.class, 42);
-		this.restTemplate.getForObject("/composers/{id}", Person.class, 42);
-		this.restTemplate.getForObject("/composers/{id}", Person.class, 42);
+		this.restClient.get().uri("/composers/{id}", 42).retrieve().body(Person.class);
+		this.restClient.get().uri("/composers/{id}", 42).retrieve().body(Person.class);
+		this.restClient.get().uri("/composers/{id}", 42).retrieve().body(Person.class);
 
 		this.mockServer.verify();
 	}
@@ -106,7 +113,7 @@ class SampleTests {
 		this.mockServer.expect(never(), requestTo("/composers/43")).andExpect(method(HttpMethod.GET))
 				.andRespond(withSuccess(responseBody, MediaType.APPLICATION_JSON));
 
-		this.restTemplate.getForObject("/composers/{id}", Person.class, 42);
+		this.restClient.get().uri("/composers/{id}", 42).retrieve().body(Person.class);
 
 		this.mockServer.verify();
 	}
@@ -120,9 +127,9 @@ class SampleTests {
 		this.mockServer.expect(never(), requestTo("/composers/43")).andExpect(method(HttpMethod.GET))
 				.andRespond(withSuccess(responseBody, MediaType.APPLICATION_JSON));
 
-		this.restTemplate.getForObject("/composers/{id}", Person.class, 42);
+		this.restClient.get().uri("/composers/{id}", 42).retrieve().body(Person.class);
 		assertThatExceptionOfType(AssertionError.class).isThrownBy(() ->
-				this.restTemplate.getForObject("/composers/{id}", Person.class, 43));
+				this.restClient.get().uri("/composers/{id}", 43).retrieve().body(Person.class));
 	}
 
 	@Test
@@ -133,7 +140,7 @@ class SampleTests {
 			.andRespond(withSuccess(responseBody, MediaType.APPLICATION_JSON));
 
 		@SuppressWarnings("unused")
-		Person ludwig = this.restTemplate.getForObject("/composers/{id}", Person.class, 42);
+		Person ludwig = this.restClient.get().uri("/composers/{id}", 42).retrieve().body(Person.class);
 
 		// hotel.getId() == 42
 		// hotel.getName().equals("Holiday Inn")
@@ -156,11 +163,11 @@ class SampleTests {
 			.andRespond(withSuccess("8", MediaType.TEXT_PLAIN));
 
 		@SuppressWarnings("unused")
-		String result1 = this.restTemplate.getForObject("/number", String.class);
+		String result1 = this.restClient.get().uri("/number").retrieve().body(String.class);
 		// result1 == "1"
 
 		@SuppressWarnings("unused")
-		String result2 = this.restTemplate.getForObject("/number", String.class);
+		String result2 = this.restClient.get().uri("/number").retrieve().body(String.class);
 		// result == "2"
 
 		try {
@@ -175,18 +182,17 @@ class SampleTests {
 	void repeatedAccessToResponseViaResource() {
 		Resource resource = new ClassPathResource("ludwig.json", getClass());
 
-		RestTemplate restTemplate = new RestTemplate();
-		restTemplate.setInterceptors(Collections.singletonList(new ContentInterceptor(resource)));
-
-		MockRestServiceServer mockServer = MockRestServiceServer.bindTo(restTemplate)
+		RestClient.Builder clientBuilder = RestClient.builder().requestInterceptor(new ContentInterceptor(resource));
+		MockRestServiceServer mockServer = MockRestServiceServer.bindTo(clientBuilder)
 				.ignoreExpectOrder(true)
 				.bufferContent()  // enable repeated reads of response body
 				.build();
+		RestClient restClient = clientBuilder.build();
 
 		mockServer.expect(requestTo("/composers/42")).andExpect(method(HttpMethod.GET))
 				.andRespond(withSuccess(resource, MediaType.APPLICATION_JSON));
 
-		restTemplate.getForObject("/composers/{id}", Person.class, 42);
+		restClient.get().uri("/composers/{id}", 42).retrieve().body(Person.class);
 
 		mockServer.verify();
 	}

spring-test/src/test/java/org/springframework/test/web/client/samples/matchers/ContentRequestMatchersIntegrationTests.java

@@ -16,17 +16,12 @@
 
 package org.springframework.test.web.client.samples.matchers;
 
-import java.net.URI;
-import java.util.List;
-
 import org.junit.jupiter.api.BeforeEach;
 import org.junit.jupiter.api.Test;
 
-import org.springframework.http.converter.StringHttpMessageConverter;
-import org.springframework.http.converter.json.JacksonJsonHttpMessageConverter;
 import org.springframework.test.web.Person;
 import org.springframework.test.web.client.MockRestServiceServer;
-import org.springframework.web.client.RestTemplate;
+import org.springframework.web.client.RestClient;
 
 import static org.assertj.core.api.Assertions.assertThatExceptionOfType;
 import static org.hamcrest.Matchers.startsWith;
@@ -44,15 +39,16 @@ import static org.springframework.test.web.client.response.MockRestResponseCreat
  */
 class ContentRequestMatchersIntegrationTests {
 
-	private final RestTemplate restTemplate = new RestTemplate();
+	private RestClient restClient;
 
-	private final MockRestServiceServer mockServer = MockRestServiceServer.createServer(this.restTemplate);
+	private MockRestServiceServer mockServer;
 
 
 	@BeforeEach
 	void setup() {
-		this.restTemplate.setMessageConverters(
-				List.of(new StringHttpMessageConverter(), new JacksonJsonHttpMessageConverter()));
+		RestClient.Builder clientBuilder = RestClient.builder();
+		this.mockServer = MockRestServiceServer.createServer(clientBuilder);
+		this.restClient = clientBuilder.build();
 	}
 
 
@@ -89,7 +85,7 @@ class ContentRequestMatchersIntegrationTests {
 	}
 
 	private void executeAndVerify(Object body) {
-		this.restTemplate.put(URI.create("/foo"), body);
+		this.restClient.put().uri("/foo").body(body).retrieve().toBodilessEntity();
 		this.mockServer.verify();
 	}
 

spring-test/src/test/java/org/springframework/test/web/client/samples/matchers/HeaderRequestMatchersIntegrationTests.java

@@ -16,18 +16,13 @@
 
 package org.springframework.test.web.client.samples.matchers;
 
-import java.net.URI;
-import java.util.List;
-
 import org.junit.jupiter.api.BeforeEach;
 import org.junit.jupiter.api.Test;
 
 import org.springframework.http.MediaType;
-import org.springframework.http.converter.StringHttpMessageConverter;
-import org.springframework.http.converter.json.JacksonJsonHttpMessageConverter;
 import org.springframework.test.web.Person;
 import org.springframework.test.web.client.MockRestServiceServer;
-import org.springframework.web.client.RestTemplate;
+import org.springframework.web.client.RestClient;
 
 import static org.hamcrest.Matchers.containsString;
 import static org.springframework.test.web.client.match.MockRestRequestMatchers.header;
@@ -43,22 +38,23 @@ class HeaderRequestMatchersIntegrationTests {
 
 	private static final String RESPONSE_BODY = "{\"name\" : \"Ludwig van Beethoven\", \"someDouble\" : \"1.6035\"}";
 
-	private final RestTemplate restTemplate = new RestTemplate();
+	private RestClient restClient;
 
-	private final MockRestServiceServer mockServer = MockRestServiceServer.createServer(this.restTemplate);
+	private MockRestServiceServer mockServer;
 
 
 	@BeforeEach
 	void setup() {
-		this.restTemplate.setMessageConverters(
-				List.of(new StringHttpMessageConverter(), new JacksonJsonHttpMessageConverter()));
+		RestClient.Builder clientBuilder = RestClient.builder();
+		this.mockServer = MockRestServiceServer.createServer(clientBuilder);
+		this.restClient = clientBuilder.build();
 	}
 
 
 	@Test
 	void string() {
 		this.mockServer.expect(requestTo("/person/1"))
-			.andExpect(header("Accept", "application/json, application/*+json"))
+			.andExpect(header("Accept", "application/json"))
 			.andRespond(withSuccess(RESPONSE_BODY, MediaType.APPLICATION_JSON));
 
 		executeAndVerify();
@@ -74,7 +70,7 @@ class HeaderRequestMatchersIntegrationTests {
 	}
 
 	private void executeAndVerify() {
-		this.restTemplate.getForObject(URI.create("/person/1"), Person.class);
+		this.restClient.get().uri("/person/1").accept(MediaType.APPLICATION_JSON).retrieve().body(Person.class);
 		this.mockServer.verify();
 	}
 

spring-test/src/test/java/org/springframework/test/web/client/samples/matchers/JsonPathRequestMatchersIntegrationTests.java

@@ -16,18 +16,17 @@
 
 package org.springframework.test.web.client.samples.matchers;
 
-import java.net.URI;
 import java.util.Arrays;
-import java.util.Collections;
 
+import org.junit.jupiter.api.BeforeEach;
 import org.junit.jupiter.api.Test;
 
-import org.springframework.http.converter.json.JacksonJsonHttpMessageConverter;
+import org.springframework.http.MediaType;
 import org.springframework.test.web.Person;
 import org.springframework.test.web.client.MockRestServiceServer;
 import org.springframework.util.LinkedMultiValueMap;
 import org.springframework.util.MultiValueMap;
-import org.springframework.web.client.RestTemplate;
+import org.springframework.web.client.RestClient;
 
 import static org.hamcrest.Matchers.containsString;
 import static org.hamcrest.Matchers.endsWith;
@@ -64,10 +63,16 @@ class JsonPathRequestMatchersIntegrationTests {
 	}
 
 
-	private final RestTemplate restTemplate =
-			new RestTemplate(Collections.singletonList(new JacksonJsonHttpMessageConverter()));
+	private RestClient restClient;
 
-	private final MockRestServiceServer mockServer = MockRestServiceServer.createServer(this.restTemplate);
+	private MockRestServiceServer mockServer;
+
+	@BeforeEach
+	void setup() {
+		RestClient.Builder clientBuilder = RestClient.builder();
+		this.mockServer = MockRestServiceServer.createServer(clientBuilder);
+		this.restClient = clientBuilder.build();
+	}
 
 
 	@Test
@@ -179,7 +184,8 @@ class JsonPathRequestMatchersIntegrationTests {
 	}
 
 	private void executeAndVerify() {
-		this.restTemplate.put(URI.create("/composers"), people);
+		this.restClient.put().uri("/composers").contentType(MediaType.APPLICATION_JSON)
+				.body(people).retrieve().toBodilessEntity();
 		this.mockServer.verify();
 	}
 

spring-test/src/test/java/org/springframework/test/web/client/samples/matchers/XmlContentRequestMatchersIntegrationTests.java

@@ -16,8 +16,6 @@
 
 package org.springframework.test.web.client.samples.matchers;
 
-import java.net.URI;
-import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.List;
 
@@ -29,11 +27,11 @@ import jakarta.xml.bind.annotation.XmlRootElement;
 import org.junit.jupiter.api.BeforeEach;
 import org.junit.jupiter.api.Test;
 
-import org.springframework.http.converter.HttpMessageConverter;
+import org.springframework.http.MediaType;
 import org.springframework.http.converter.xml.Jaxb2RootElementHttpMessageConverter;
 import org.springframework.test.web.Person;
 import org.springframework.test.web.client.MockRestServiceServer;
-import org.springframework.web.client.RestTemplate;
+import org.springframework.web.client.RestClient;
 
 import static org.hamcrest.Matchers.hasXPath;
 import static org.springframework.test.web.client.match.MockRestRequestMatchers.content;
@@ -61,7 +59,7 @@ class XmlContentRequestMatchersIntegrationTests {
 
 	private MockRestServiceServer mockServer;
 
-	private RestTemplate restTemplate;
+	private RestClient restClient;
 
 	private PeopleWrapper people;
 
@@ -76,13 +74,11 @@ class XmlContentRequestMatchersIntegrationTests {
 
 		this.people = new PeopleWrapper(composers);
 
-		List<HttpMessageConverter<?>> converters = new ArrayList<>();
-		converters.add(new Jaxb2RootElementHttpMessageConverter());
+		RestClient.Builder clientBuilder = RestClient.builder().configureMessageConverters(converters ->
+				converters.registerDefaults().withXmlConverter(new Jaxb2RootElementHttpMessageConverter()));
 
-		this.restTemplate = new RestTemplate();
-		this.restTemplate.setMessageConverters(converters);
-
-		this.mockServer = MockRestServiceServer.createServer(this.restTemplate);
+		this.mockServer = MockRestServiceServer.createServer(clientBuilder);
+		this.restClient = clientBuilder.build();
 	}
 
 	@Test
@@ -106,7 +102,8 @@ class XmlContentRequestMatchersIntegrationTests {
 	}
 
 	private void executeAndVerify() {
-		this.restTemplate.put(URI.create("/composers"), this.people);
+		this.restClient.put().uri("/composers").contentType(MediaType.APPLICATION_XML)
+				.body(this.people).retrieve().toBodilessEntity();
 		this.mockServer.verify();
 	}
 

spring-test/src/test/java/org/springframework/test/web/client/samples/matchers/XpathRequestMatchersIntegrationTests.java

@@ -16,8 +16,6 @@
 
 package org.springframework.test.web.client.samples.matchers;
 
-import java.net.URI;
-import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.Collections;
 import java.util.List;
@@ -31,11 +29,11 @@ import jakarta.xml.bind.annotation.XmlRootElement;
 import org.junit.jupiter.api.BeforeEach;
 import org.junit.jupiter.api.Test;
 
-import org.springframework.http.converter.HttpMessageConverter;
+import org.springframework.http.MediaType;
 import org.springframework.http.converter.xml.Jaxb2RootElementHttpMessageConverter;
 import org.springframework.test.web.Person;
 import org.springframework.test.web.client.MockRestServiceServer;
-import org.springframework.web.client.RestTemplate;
+import org.springframework.web.client.RestClient;
 
 import static org.hamcrest.Matchers.closeTo;
 import static org.hamcrest.Matchers.equalTo;
@@ -61,7 +59,7 @@ class XpathRequestMatchersIntegrationTests {
 
 	private MockRestServiceServer mockServer;
 
-	private RestTemplate restTemplate;
+	private RestClient restClient;
 
 	private PeopleWrapper people;
 
@@ -80,13 +78,11 @@ class XpathRequestMatchersIntegrationTests {
 
 		this.people = new PeopleWrapper(composers, performers);
 
-		List<HttpMessageConverter<?>> converters = new ArrayList<>();
-		converters.add(new Jaxb2RootElementHttpMessageConverter());
+		RestClient.Builder clientBuilder = RestClient.builder().configureMessageConverters(converters ->
+				converters.registerDefaults().withXmlConverter(new Jaxb2RootElementHttpMessageConverter()));
 
-		this.restTemplate = new RestTemplate();
-		this.restTemplate.setMessageConverters(converters);
-
-		this.mockServer = MockRestServiceServer.createServer(this.restTemplate);
+		this.mockServer = MockRestServiceServer.createServer(clientBuilder);
+		this.restClient = clientBuilder.build();
 	}
 
 
@@ -190,7 +186,8 @@ class XpathRequestMatchersIntegrationTests {
 	}
 
 	private void executeAndVerify() {
-		this.restTemplate.put(URI.create("/composers"), this.people);
+		this.restClient.put().uri("/composers").contentType(MediaType.APPLICATION_XML)
+				.body(this.people).retrieve().toBodilessEntity();
 		this.mockServer.verify();
 	}
 

spring-web/src/test/java/org/springframework/http/server/reactive/AsyncIntegrationTests.java

@@ -16,7 +16,6 @@
 
 package org.springframework.http.server.reactive;
 
-import java.net.URI;
 import java.time.Duration;
 
 import reactor.core.publisher.Flux;
@@ -25,9 +24,7 @@ import reactor.core.scheduler.Scheduler;
 import reactor.core.scheduler.Schedulers;
 
 import org.springframework.core.io.buffer.DefaultDataBufferFactory;
-import org.springframework.http.RequestEntity;
 import org.springframework.http.ResponseEntity;
-import org.springframework.web.client.RestTemplate;
 import org.springframework.web.testfixture.http.server.reactive.bootstrap.AbstractHttpHandlerIntegrationTests;
 import org.springframework.web.testfixture.http.server.reactive.bootstrap.HttpServer;
 
@@ -51,8 +48,7 @@ class AsyncIntegrationTests extends AbstractHttpHandlerIntegrationTests {
 	void basicTest(HttpServer httpServer) throws Exception {
 		startServer(httpServer);
 
-		URI url = URI.create("http://localhost:" + port);
-		ResponseEntity<String> response = new RestTemplate().exchange(RequestEntity.get(url).build(), String.class);
+		ResponseEntity<String> response = getRestClient().get().retrieve().toEntity(String.class);
 
 		assertThat(response.getBody()).isEqualTo("hello");
 	}

spring-web/src/test/java/org/springframework/http/server/reactive/CookieIntegrationTests.java

@@ -16,7 +16,6 @@
 
 package org.springframework.http.server.reactive;
 
-import java.net.URI;
 import java.util.ArrayList;
 import java.util.List;
 import java.util.Map;
@@ -24,10 +23,8 @@ import java.util.Map;
 import reactor.core.publisher.Mono;
 
 import org.springframework.http.HttpCookie;
-import org.springframework.http.RequestEntity;
 import org.springframework.http.ResponseCookie;
 import org.springframework.http.ResponseEntity;
-import org.springframework.web.client.RestTemplate;
 import org.springframework.web.testfixture.http.server.reactive.bootstrap.AbstractHttpHandlerIntegrationTests;
 import org.springframework.web.testfixture.http.server.reactive.bootstrap.HttpServer;
 
@@ -52,10 +49,9 @@ class CookieIntegrationTests extends AbstractHttpHandlerIntegrationTests {
 	public void basicTest(HttpServer httpServer) throws Exception {
 		startServer(httpServer);
 
-		URI url = URI.create("http://localhost:" + port);
-		String header = "SID=31d4d96e407aad42; lang=en-US";
-		ResponseEntity<Void> response = new RestTemplate().exchange(
-				RequestEntity.get(url).header("Cookie", header).build(), Void.class);
+		ResponseEntity<Void> response = getRestClient().get()
+				.header("Cookie", "SID=31d4d96e407aad42; lang=en-US")
+				.retrieve().toBodilessEntity();
 
 		Map<String, List<HttpCookie>> requestCookies = this.cookieHandler.requestCookies;
 		assertThat(requestCookies).hasSize(2);
@@ -79,10 +75,9 @@ class CookieIntegrationTests extends AbstractHttpHandlerIntegrationTests {
 	public void partitionedAttributeTest(HttpServer httpServer) throws Exception {
 		startServer(httpServer);
 
-		URI url = URI.create("http://localhost:" + port);
-		String header = "SID=31d4d96e407aad42; lang=en-US";
-		ResponseEntity<Void> response = new RestTemplate().exchange(
-				RequestEntity.get(url).header("Cookie", header).build(), Void.class);
+		ResponseEntity<Void> response = getRestClient().get()
+				.header("Cookie", "SID=31d4d96e407aad42; lang=en-US")
+				.retrieve().toBodilessEntity();
 
 		List<String> headerValues = response.getHeaders().get("Set-Cookie");
 		assertThat(headerValues).hasSize(2);
@@ -97,10 +92,9 @@ class CookieIntegrationTests extends AbstractHttpHandlerIntegrationTests {
 	public void cookiesWithSameNameTest(HttpServer httpServer) throws Exception {
 		startServer(httpServer);
 
-		URI url = new URI("http://localhost:" + port);
-		String header = "SID=31d4d96e407aad42; lang=en-US; lang=zh-CN";
-		new RestTemplate().exchange(
-				RequestEntity.get(url).header("Cookie", header).build(), Void.class);
+		ResponseEntity<Void> response = getRestClient().get()
+				.header("Cookie", "SID=31d4d96e407aad42; lang=en-US; lang=zh-CN")
+				.retrieve().toBodilessEntity();
 
 		Map<String, List<HttpCookie>> requestCookies = this.cookieHandler.requestCookies;
 		assertThat(requestCookies).hasSize(2);

spring-web/src/test/java/org/springframework/http/server/reactive/EchoHandlerIntegrationTests.java

@@ -16,14 +16,11 @@
 
 package org.springframework.http.server.reactive;
 
-import java.net.URI;
 import java.util.Random;
 
 import reactor.core.publisher.Mono;
 
-import org.springframework.http.RequestEntity;
 import org.springframework.http.ResponseEntity;
-import org.springframework.web.client.RestTemplate;
 import org.springframework.web.testfixture.http.server.reactive.bootstrap.AbstractHttpHandlerIntegrationTests;
 import org.springframework.web.testfixture.http.server.reactive.bootstrap.HttpServer;
 
@@ -49,11 +46,8 @@ class EchoHandlerIntegrationTests extends AbstractHttpHandlerIntegrationTests {
 	public void echo(HttpServer httpServer) throws Exception {
 		startServer(httpServer);
 
-		RestTemplate restTemplate = new RestTemplate();
-
 		byte[] body = randomBytes();
-		RequestEntity<byte[]> request = RequestEntity.post(URI.create("http://localhost:" + port)).body(body);
-		ResponseEntity<byte[]> response = restTemplate.exchange(request, byte[].class);
+		ResponseEntity<byte[]> response = getRestClient().post().body(body).retrieve().toEntity(byte[].class);
 
 		assertThat(response.getBody()).isEqualTo(body);
 	}

spring-web/src/test/java/org/springframework/http/server/reactive/ErrorHandlerIntegrationTests.java

@@ -21,10 +21,9 @@ import java.net.URI;
 import reactor.core.publisher.Mono;
 
 import org.springframework.http.HttpStatus;
+import org.springframework.http.HttpStatusCode;
 import org.springframework.http.ResponseEntity;
-import org.springframework.web.client.NoOpResponseErrorHandler;
-import org.springframework.web.client.ResponseErrorHandler;
-import org.springframework.web.client.RestTemplate;
+import org.springframework.web.client.RestClient;
 import org.springframework.web.testfixture.http.server.reactive.bootstrap.AbstractHttpHandlerIntegrationTests;
 import org.springframework.web.testfixture.http.server.reactive.bootstrap.HttpServer;
 import org.springframework.web.testfixture.http.server.reactive.bootstrap.JettyCoreHttpServer;
@@ -37,8 +36,6 @@ import static org.assertj.core.api.Assertions.assertThat;
  */
 class ErrorHandlerIntegrationTests extends AbstractHttpHandlerIntegrationTests {
 
-	private static final ResponseErrorHandler NO_OP_ERROR_HANDLER = new NoOpResponseErrorHandler();
-
 	private final ErrorHandler handler = new ErrorHandler();
 
 
@@ -47,16 +44,20 @@ class ErrorHandlerIntegrationTests extends AbstractHttpHandlerIntegrationTests {
 		return handler;
 	}
 
+	@Override
+	protected RestClient initRestClient(RestClient.Builder builder) {
+		return builder
+				.defaultStatusHandler(HttpStatusCode::is5xxServerError, (req, res) -> {})
+				.defaultStatusHandler(HttpStatusCode::is4xxClientError, (req, res) -> {})
+				.build();
+	}
 
 	@ParameterizedHttpServerTest
 	void responseBodyError(HttpServer httpServer) throws Exception {
 		startServer(httpServer);
 
-		RestTemplate restTemplate = new RestTemplate();
-		restTemplate.setErrorHandler(NO_OP_ERROR_HANDLER);
-
-		URI url = URI.create("http://localhost:" + port + "/response-body-error");
-		ResponseEntity<String> response = restTemplate.getForEntity(url, String.class);
+		ResponseEntity<String> response = getRestClient().get().uri("/response-body-error")
+				.retrieve().toEntity(String.class);
 
 		assertThat(response.getStatusCode()).isEqualTo(HttpStatus.INTERNAL_SERVER_ERROR);
 	}
@@ -65,11 +66,8 @@ class ErrorHandlerIntegrationTests extends AbstractHttpHandlerIntegrationTests {
 	void handlingError(HttpServer httpServer) throws Exception {
 		startServer(httpServer);
 
-		RestTemplate restTemplate = new RestTemplate();
-		restTemplate.setErrorHandler(NO_OP_ERROR_HANDLER);
-
-		URI url = URI.create("http://localhost:" + port + "/handling-error");
-		ResponseEntity<String> response = restTemplate.getForEntity(url, String.class);
+		ResponseEntity<String> response = getRestClient().get().uri("/handling-error")
+				.retrieve().toEntity(String.class);
 
 		assertThat(response.getStatusCode()).isEqualTo(HttpStatus.INTERNAL_SERVER_ERROR);
 	}
@@ -78,11 +76,10 @@ class ErrorHandlerIntegrationTests extends AbstractHttpHandlerIntegrationTests {
 	void emptyPathSegments(HttpServer httpServer) throws Exception {
 		startServer(httpServer);
 
-		RestTemplate restTemplate = new RestTemplate();
-		restTemplate.setErrorHandler(NO_OP_ERROR_HANDLER);
 
-		URI url = URI.create("http://localhost:" + port + "//");
-		ResponseEntity<String> response = restTemplate.getForEntity(url, String.class);
+		ResponseEntity<String> response = getRestClient().get()
+				.uri(URI.create("http://localhost:" + this.server.getPort() + "//"))
+				.retrieve().toEntity(String.class);
 
 		// Jetty 10+ rejects empty path segments, see https://github.com/eclipse/jetty.project/issues/6302,
 		// but an application can apply CompactPathRule via RewriteHandler:

spring-web/src/test/java/org/springframework/http/server/reactive/MultipartHttpHandlerIntegrationTests.java

@@ -16,8 +16,6 @@
 
 package org.springframework.http.server.reactive;
 
-import java.net.URI;
-
 import reactor.core.publisher.Mono;
 import reactor.test.StepVerifier;
 
@@ -27,14 +25,12 @@ import org.springframework.http.HttpEntity;
 import org.springframework.http.HttpHeaders;
 import org.springframework.http.HttpStatus;
 import org.springframework.http.MediaType;
-import org.springframework.http.RequestEntity;
 import org.springframework.http.ResponseEntity;
 import org.springframework.http.codec.multipart.FilePart;
 import org.springframework.http.codec.multipart.FormFieldPart;
 import org.springframework.http.codec.multipart.Part;
 import org.springframework.util.LinkedMultiValueMap;
 import org.springframework.util.MultiValueMap;
-import org.springframework.web.client.RestTemplate;
 import org.springframework.web.server.ServerWebExchange;
 import org.springframework.web.server.WebHandler;
 import org.springframework.web.server.adapter.HttpWebHandlerAdapter;
@@ -81,9 +77,9 @@ class MultipartHttpHandlerIntegrationTests extends AbstractHttpHandlerIntegratio
 		parts.add("fooPart", fooPart);
 		parts.add("barPart", barPart);
 
-		URI url = URI.create("http://localhost:" + port + "/form-parts");
-		ResponseEntity<Void> response = new RestTemplate().exchange(
-				RequestEntity.post(url).contentType(mediaType).body(parts), Void.class);
+		ResponseEntity<Void> response = getRestClient().post().uri("/form-parts")
+				.contentType(MediaType.MULTIPART_FORM_DATA).body(parts)
+				.retrieve().toBodilessEntity();
 
 		assertThat(response.getStatusCode()).isEqualTo(HttpStatus.OK);
 	}

spring-web/src/test/java/org/springframework/http/server/reactive/RandomHandlerIntegrationTests.java

@@ -16,7 +16,6 @@
 
 package org.springframework.http.server.reactive;
 
-import java.net.URI;
 import java.util.Random;
 
 import org.reactivestreams.Publisher;
@@ -25,9 +24,7 @@ import reactor.core.publisher.Mono;
 
 import org.springframework.core.io.buffer.DataBuffer;
 import org.springframework.core.io.buffer.DefaultDataBufferFactory;
-import org.springframework.http.RequestEntity;
 import org.springframework.http.ResponseEntity;
-import org.springframework.web.client.RestTemplate;
 import org.springframework.web.testfixture.http.server.reactive.bootstrap.AbstractHttpHandlerIntegrationTests;
 import org.springframework.web.testfixture.http.server.reactive.bootstrap.HttpServer;
 
@@ -59,11 +56,7 @@ class RandomHandlerIntegrationTests extends AbstractHttpHandlerIntegrationTests
 
 		// TODO: fix Reactor support
 
-		RestTemplate restTemplate = new RestTemplate();
-
-		byte[] body = randomBytes();
-		RequestEntity<byte[]> request = RequestEntity.post(URI.create("http://localhost:" + port)).body(body);
-		ResponseEntity<byte[]> response = restTemplate.exchange(request, byte[].class);
+		ResponseEntity<byte[]> response = getRestClient().post().body(randomBytes()).retrieve().toEntity(byte[].class);
 
 		assertThat(response.getBody()).isNotNull();
 		assertThat(response.getHeaders().getContentLength()).isEqualTo(RESPONSE_SIZE);

spring-web/src/test/java/org/springframework/http/server/reactive/ServerHttpRequestIntegrationTests.java

@@ -21,9 +21,7 @@ import java.net.URI;
 import reactor.core.publisher.Mono;
 
 import org.springframework.http.HttpStatus;
-import org.springframework.http.RequestEntity;
 import org.springframework.http.ResponseEntity;
-import org.springframework.web.client.RestTemplate;
 import org.springframework.web.testfixture.http.server.reactive.bootstrap.AbstractHttpHandlerIntegrationTests;
 import org.springframework.web.testfixture.http.server.reactive.bootstrap.HttpServer;
 
@@ -44,9 +42,7 @@ class ServerHttpRequestIntegrationTests extends AbstractHttpHandlerIntegrationTe
 	void checkUri(HttpServer httpServer) throws Exception {
 		startServer(httpServer);
 
-		URI url = URI.create("http://localhost:" + port + "/foo?param=bar");
-		RequestEntity<Void> request = RequestEntity.post(url).build();
-		ResponseEntity<Void> response = new RestTemplate().exchange(request, Void.class);
+		ResponseEntity<Void> response = getRestClient().post().uri("/foo?param=bar").retrieve().toBodilessEntity();
 		assertThat(response.getStatusCode()).isEqualTo(HttpStatus.OK);
 	}
 

spring-web/src/test/java/org/springframework/http/server/reactive/ServerHttpsRequestIntegrationTests.java

@@ -32,10 +32,9 @@ import org.junit.jupiter.api.Test;
 import reactor.core.publisher.Mono;
 
 import org.springframework.http.HttpStatus;
-import org.springframework.http.RequestEntity;
 import org.springframework.http.ResponseEntity;
 import org.springframework.http.client.HttpComponentsClientHttpRequestFactory;
-import org.springframework.web.client.RestTemplate;
+import org.springframework.web.client.RestClient;
 import org.springframework.web.testfixture.http.server.reactive.bootstrap.HttpServer;
 import org.springframework.web.testfixture.http.server.reactive.bootstrap.ReactorHttpsServer;
 
@@ -52,10 +51,7 @@ class ServerHttpsRequestIntegrationTests {
 
 	private final HttpServer server = new ReactorHttpsServer();
 
-	private int port;
-
-	private RestTemplate restTemplate;
-
+	private RestClient restClient;
 
 	@BeforeEach
 	void startServer() throws Exception {
@@ -63,8 +59,6 @@ class ServerHttpsRequestIntegrationTests {
 		this.server.afterPropertiesSet();
 		this.server.start();
 
-		// Set dynamically chosen port
-		this.port = this.server.getPort();
 
 		SSLContextBuilder builder = new SSLContextBuilder();
 		builder.loadTrustMaterial(new TrustSelfSignedStrategy());
@@ -77,7 +71,8 @@ class ServerHttpsRequestIntegrationTests {
 				setConnectionManager(connectionManager).build();
 		HttpComponentsClientHttpRequestFactory requestFactory =
 				new HttpComponentsClientHttpRequestFactory(httpclient);
-		this.restTemplate = new RestTemplate(requestFactory);
+		this.restClient = RestClient.builder().baseUrl("https://localhost:" + this.server.getPort())
+				.requestFactory(requestFactory).build();
 	}
 
 	@AfterEach
@@ -87,9 +82,7 @@ class ServerHttpsRequestIntegrationTests {
 
 	@Test
 	void checkUri() {
-		URI url = URI.create("https://localhost:" + port + "/foo?param=bar");
-		RequestEntity<Void> request = RequestEntity.post(url).build();
-		ResponseEntity<Void> response = this.restTemplate.exchange(request, Void.class);
+		ResponseEntity<Void> response = this.restClient.post().uri("/foo?param=bar").retrieve().toBodilessEntity();
 		assertThat(response.getStatusCode()).isEqualTo(HttpStatus.OK);
 	}
 

spring-web/src/test/java/org/springframework/http/server/reactive/WriteOnlyHandlerIntegrationTests.java

@@ -16,7 +16,6 @@
 
 package org.springframework.http.server.reactive;
 
-import java.net.URI;
 import java.nio.charset.StandardCharsets;
 import java.util.Random;
 
@@ -24,9 +23,7 @@ import reactor.core.publisher.Flux;
 import reactor.core.publisher.Mono;
 
 import org.springframework.core.io.buffer.DataBuffer;
-import org.springframework.http.RequestEntity;
 import org.springframework.http.ResponseEntity;
-import org.springframework.web.client.RestTemplate;
 import org.springframework.web.testfixture.http.server.reactive.bootstrap.AbstractHttpHandlerIntegrationTests;
 import org.springframework.web.testfixture.http.server.reactive.bootstrap.HttpServer;
 
@@ -54,12 +51,9 @@ class WriteOnlyHandlerIntegrationTests extends AbstractHttpHandlerIntegrationTes
 	void writeOnly(HttpServer httpServer) throws Exception {
 		startServer(httpServer);
 
-		RestTemplate restTemplate = new RestTemplate();
-
 		this.body = randomBytes();
-		RequestEntity<byte[]> request = RequestEntity.post(URI.create("http://localhost:" + port))
-				.body("".getBytes(StandardCharsets.UTF_8));
-		ResponseEntity<byte[]> response = restTemplate.exchange(request, byte[].class);
+		ResponseEntity<byte[]> response = getRestClient().post().body("".getBytes(StandardCharsets.UTF_8))
+				.retrieve().toEntity(byte[].class);
 
 		assertThat(response.getBody()).isEqualTo(body);
 	}

spring-web/src/test/java/org/springframework/http/server/reactive/ZeroCopyIntegrationTests.java

@@ -17,17 +17,14 @@
 package org.springframework.http.server.reactive;
 
 import java.io.File;
-import java.net.URI;
 
 import reactor.core.publisher.Mono;
 
 import org.springframework.core.io.ClassPathResource;
 import org.springframework.core.io.Resource;
 import org.springframework.http.MediaType;
-import org.springframework.http.RequestEntity;
 import org.springframework.http.ResponseEntity;
 import org.springframework.http.ZeroCopyHttpOutputMessage;
-import org.springframework.web.client.RestTemplate;
 import org.springframework.web.testfixture.http.server.reactive.bootstrap.AbstractHttpHandlerIntegrationTests;
 import org.springframework.web.testfixture.http.server.reactive.bootstrap.HttpServer;
 import org.springframework.web.testfixture.http.server.reactive.bootstrap.JettyCoreHttpServer;
@@ -59,9 +56,7 @@ class ZeroCopyIntegrationTests extends AbstractHttpHandlerIntegrationTests {
 
 		startServer(httpServer);
 
-		URI url = URI.create("http://localhost:" + port);
-		RequestEntity<?> request = RequestEntity.get(url).build();
-		ResponseEntity<byte[]> response = new RestTemplate().exchange(request, byte[].class);
+		ResponseEntity<byte[]> response = getRestClient().get().retrieve().toEntity(byte[].class);
 
 		assertThat(response.hasBody()).isTrue();
 		assertThat(response.getHeaders().getContentLength()).isEqualTo(springLogoResource.contentLength());

spring-web/src/test/java/org/springframework/web/bind/support/WebRequestDataBinderIntegrationTests.java

@@ -38,11 +38,12 @@ import org.junit.jupiter.api.TestInstance.Lifecycle;
 
 import org.springframework.core.io.ClassPathResource;
 import org.springframework.core.io.Resource;
+import org.springframework.http.MediaType;
 import org.springframework.http.client.HttpComponentsClientHttpRequestFactory;
 import org.springframework.util.FileSystemUtils;
 import org.springframework.util.LinkedMultiValueMap;
 import org.springframework.util.MultiValueMap;
-import org.springframework.web.client.RestTemplate;
+import org.springframework.web.client.RestClient;
 import org.springframework.web.context.request.ServletWebRequest;
 
 import static org.assertj.core.api.Assertions.assertThat;
@@ -58,12 +59,10 @@ class WebRequestDataBinderIntegrationTests {
 
 	private final PartListServlet partListServlet = new PartListServlet();
 
-	private final RestTemplate template = new RestTemplate(new HttpComponentsClientHttpRequestFactory());
+	private RestClient restClient;
 
 	private Server jettyServer;
 
-	private String baseUrl;
-
 	private Path tempDirectory;
 
 
@@ -91,7 +90,8 @@ class WebRequestDataBinderIntegrationTests {
 
 		Connector[] connectors = jettyServer.getConnectors();
 		NetworkConnector connector = (NetworkConnector) connectors[0];
-		baseUrl = "http://localhost:" + connector.getLocalPort();
+		this.restClient = RestClient.builder().baseUrl("http://localhost:" + connector.getLocalPort())
+				.requestFactory(new HttpComponentsClientHttpRequestFactory()).build();
 	}
 
 	@AfterAll
@@ -117,7 +117,9 @@ class WebRequestDataBinderIntegrationTests {
 		parts.add("firstPart", firstPart);
 		parts.add("secondPart", "secondValue");
 
-		template.postForLocation(baseUrl + "/parts", parts);
+		this.restClient.post().uri("/parts")
+				.contentType(MediaType.MULTIPART_FORM_DATA).body(parts)
+				.retrieve().toBodilessEntity();
 
 		assertThat(bean.getFirstPart()).isNotNull();
 		assertThat(bean.getSecondPart()).isNotNull();
@@ -134,7 +136,9 @@ class WebRequestDataBinderIntegrationTests {
 		Resource logo = new ClassPathResource("/org/springframework/http/converter/logo.jpg");
 		parts.add("partList", logo);
 
-		template.postForLocation(baseUrl + "/partlist", parts);
+		this.restClient.post().uri("/partlist")
+				.contentType(MediaType.MULTIPART_FORM_DATA).body(parts)
+				.retrieve().toBodilessEntity();
 
 		assertThat(bean.getPartList()).isNotNull();
 		assertThat(bean.getPartList()).hasSize(parts.get("partList").size());

spring-web/src/test/java/org/springframework/web/client/RestClientObservationTests.java

@@ -35,6 +35,7 @@ import org.springframework.http.HttpHeaders;
 import org.springframework.http.HttpMethod;
 import org.springframework.http.HttpRequest;
 import org.springframework.http.HttpStatus;
+import org.springframework.http.HttpStatusCode;
 import org.springframework.http.MediaType;
 import org.springframework.http.client.ClientHttpRequest;
 import org.springframework.http.client.ClientHttpRequestExecution;
@@ -49,6 +50,7 @@ import org.springframework.util.StreamUtils;
 
 import static org.assertj.core.api.Assertions.assertThat;
 import static org.assertj.core.api.Assertions.assertThatExceptionOfType;
+import static org.mockito.ArgumentMatchers.any;
 import static org.mockito.BDDMockito.given;
 import static org.mockito.BDDMockito.willThrow;
 import static org.mockito.Mockito.mock;
@@ -135,15 +137,15 @@ class RestClientObservationTests {
 
 	@Test
 	void shouldContributeServerErrorOutcome() throws Exception {
-		ResponseErrorHandler errorHandler = mock();
-		given(errorHandler.hasError(response)).willReturn(true);
-		this.client = this.client.mutate().defaultStatusHandler(errorHandler).build();
+		RestClient.ResponseSpec.ErrorHandler errorHandler = mock();
+		this.client = this.client.mutate()
+				.defaultStatusHandler(HttpStatusCode::is5xxServerError, errorHandler).build();
 
 		String url = "https://example.org";
 		mockSentRequest(GET, url);
 		mockResponseStatus(HttpStatus.INTERNAL_SERVER_ERROR);
 		willThrow(new HttpServerErrorException(HttpStatus.INTERNAL_SERVER_ERROR))
-				.given(errorHandler).handleError(URI.create(url), GET, response);
+				.given(errorHandler).handle(any(), any());
 
 		assertThatExceptionOfType(HttpServerErrorException.class).isThrownBy(() ->
 				client.get().uri(url).retrieve().toBodilessEntity());
@@ -257,7 +259,8 @@ class RestClientObservationTests {
 	@Test
 	void openScopeWithObservation() throws Exception {
 		this.client = createBuilder().requestInterceptor(new ObservationContextInterceptor(this.observationRegistry))
-				.defaultStatusHandler(new ObservationErrorHandler(this.observationRegistry)).build();
+				.defaultStatusHandler(HttpStatusCode::is2xxSuccessful, new ObservationErrorHandler(this.observationRegistry))
+				.build();
 		mockSentRequest(GET, "https://example.org");
 		mockResponseStatus(HttpStatus.OK);
 		mockResponseBody("Hello World", MediaType.TEXT_PLAIN);
@@ -334,7 +337,7 @@ class RestClientObservationTests {
 		}
 	}
 
-	static class ObservationErrorHandler implements ResponseErrorHandler {
+	static class ObservationErrorHandler implements RestClient.ResponseSpec.ErrorHandler {
 
 		final TestObservationRegistry observationRegistry;
 
@@ -343,14 +346,10 @@ class RestClientObservationTests {
 		}
 
 		@Override
-		public boolean hasError(ClientHttpResponse response) {
-			return true;
-		}
-
-		@Override
-		public void handleError(URI uri, HttpMethod httpMethod, ClientHttpResponse response) {
+		public void handle(HttpRequest request, ClientHttpResponse response) throws IOException {
 			assertThat(this.observationRegistry.getCurrentObservationScope()).isNotNull();
 		}
+
 	}
 
 }

spring-web/src/test/java/org/springframework/web/server/session/WebSessionIntegrationTests.java

@@ -16,7 +16,6 @@
 
 package org.springframework.web.server.session;
 
-import java.net.URI;
 import java.time.Clock;
 import java.time.Duration;
 import java.util.List;
@@ -26,10 +25,8 @@ import reactor.core.publisher.Mono;
 
 import org.springframework.http.HttpHeaders;
 import org.springframework.http.HttpStatus;
-import org.springframework.http.RequestEntity;
 import org.springframework.http.ResponseEntity;
 import org.springframework.http.server.reactive.HttpHandler;
-import org.springframework.web.client.RestTemplate;
 import org.springframework.web.server.ServerWebExchange;
 import org.springframework.web.server.WebHandler;
 import org.springframework.web.server.WebSession;
@@ -47,8 +44,6 @@ import static org.assertj.core.api.Assertions.assertThat;
  */
 class WebSessionIntegrationTests extends AbstractHttpHandlerIntegrationTests {
 
-	private final RestTemplate restTemplate = new RestTemplate();
-
 	private final DefaultWebSessionManager sessionManager = new DefaultWebSessionManager();
 
 	private final TestWebHandler handler = new TestWebHandler();
@@ -64,16 +59,14 @@ class WebSessionIntegrationTests extends AbstractHttpHandlerIntegrationTests {
 	public void createSession(HttpServer httpServer) throws Exception {
 		startServer(httpServer);
 
-		RequestEntity<Void> request = RequestEntity.get(createUri()).build();
-		ResponseEntity<Void> response = this.restTemplate.exchange(request, Void.class);
+		ResponseEntity<Void> response = getRestClient().get().retrieve().toBodilessEntity();
 
 		assertThat(response.getStatusCode()).isEqualTo(HttpStatus.OK);
 		String id = extractSessionId(response.getHeaders());
 		assertThat(id).isNotNull();
 		assertThat(this.handler.getSessionRequestCount()).isEqualTo(1);
 
-		request = RequestEntity.get(createUri()).header("Cookie", "SESSION=" + id).build();
-		response = this.restTemplate.exchange(request, Void.class);
+		response = getRestClient().get().cookie("SESSION", id).retrieve().toBodilessEntity();
 
 		assertThat(response.getStatusCode()).isEqualTo(HttpStatus.OK);
 		assertThat(response.getHeaders().get("Set-Cookie")).isNull();
@@ -85,8 +78,7 @@ class WebSessionIntegrationTests extends AbstractHttpHandlerIntegrationTests {
 		startServer(httpServer);
 
 		// First request: no session yet, new session created
-		RequestEntity<Void> request = RequestEntity.get(createUri()).build();
-		ResponseEntity<Void> response = this.restTemplate.exchange(request, Void.class);
+		ResponseEntity<Void> response = getRestClient().get().retrieve().toBodilessEntity();
 
 		assertThat(response.getStatusCode()).isEqualTo(HttpStatus.OK);
 		String id = extractSessionId(response.getHeaders());
@@ -94,8 +86,7 @@ class WebSessionIntegrationTests extends AbstractHttpHandlerIntegrationTests {
 		assertThat(this.handler.getSessionRequestCount()).isEqualTo(1);
 
 		// Second request: same session
-		request = RequestEntity.get(createUri()).header("Cookie", "SESSION=" + id).build();
-		response = this.restTemplate.exchange(request, Void.class);
+		response = getRestClient().get().cookie("SESSION", id).retrieve().toBodilessEntity();
 
 		assertThat(response.getStatusCode()).isEqualTo(HttpStatus.OK);
 		assertThat(response.getHeaders().get("Set-Cookie")).isNull();
@@ -108,8 +99,7 @@ class WebSessionIntegrationTests extends AbstractHttpHandlerIntegrationTests {
 		store.setClock(Clock.offset(store.getClock(), Duration.ofMinutes(31)));
 
 		// Third request: expired session, new session created
-		request = RequestEntity.get(createUri()).header("Cookie", "SESSION=" + id).build();
-		response = this.restTemplate.exchange(request, Void.class);
+		response = getRestClient().get().cookie("SESSION", id).retrieve().toBodilessEntity();
 
 		assertThat(response.getStatusCode()).isEqualTo(HttpStatus.OK);
 		id = extractSessionId(response.getHeaders());
@@ -122,8 +112,7 @@ class WebSessionIntegrationTests extends AbstractHttpHandlerIntegrationTests {
 		startServer(httpServer);
 
 		// First request: no session yet, new session created
-		RequestEntity<Void> request = RequestEntity.get(createUri()).build();
-		ResponseEntity<Void> response = this.restTemplate.exchange(request, Void.class);
+		ResponseEntity<Void> response = getRestClient().get().retrieve().toBodilessEntity();
 
 		assertThat(response.getStatusCode()).isEqualTo(HttpStatus.OK);
 		String id = extractSessionId(response.getHeaders());
@@ -134,9 +123,7 @@ class WebSessionIntegrationTests extends AbstractHttpHandlerIntegrationTests {
 		store.setClock(Clock.offset(store.getClock(), Duration.ofMinutes(31)));
 
 		// Second request: session expires
-		URI uri = URI.create("http://localhost:" + this.port + "/?expire");
-		request = RequestEntity.get(uri).header("Cookie", "SESSION=" + id).build();
-		response = this.restTemplate.exchange(request, Void.class);
+		response = getRestClient().get().uri("/?expire").cookie("SESSION", id).retrieve().toBodilessEntity();
 
 		assertThat(response.getStatusCode()).isEqualTo(HttpStatus.OK);
 		String value = response.getHeaders().getFirst("Set-Cookie");
@@ -149,8 +136,7 @@ class WebSessionIntegrationTests extends AbstractHttpHandlerIntegrationTests {
 		startServer(httpServer);
 
 		// First request: no session yet, new session created
-		RequestEntity<Void> request = RequestEntity.get(createUri()).build();
-		ResponseEntity<Void> response = this.restTemplate.exchange(request, Void.class);
+		ResponseEntity<Void> response = getRestClient().get().retrieve().toBodilessEntity();
 
 		assertThat(response.getStatusCode()).isEqualTo(HttpStatus.OK);
 		String oldId = extractSessionId(response.getHeaders());
@@ -158,9 +144,7 @@ class WebSessionIntegrationTests extends AbstractHttpHandlerIntegrationTests {
 		assertThat(this.handler.getSessionRequestCount()).isEqualTo(1);
 
 		// Second request: session id changes
-		URI uri = URI.create("http://localhost:" + this.port + "/?changeId");
-		request = RequestEntity.get(uri).header("Cookie", "SESSION=" + oldId).build();
-		response = this.restTemplate.exchange(request, Void.class);
+		response = getRestClient().get().uri("/?changeId").cookie("SESSION", oldId).retrieve().toBodilessEntity();
 
 		assertThat(response.getStatusCode()).isEqualTo(HttpStatus.OK);
 		String newId = extractSessionId(response.getHeaders());
@@ -174,17 +158,14 @@ class WebSessionIntegrationTests extends AbstractHttpHandlerIntegrationTests {
 		startServer(httpServer);
 
 		// First request: no session yet, new session created
-		RequestEntity<Void> request = RequestEntity.get(createUri()).build();
-		ResponseEntity<Void> response = this.restTemplate.exchange(request, Void.class);
+		ResponseEntity<Void> response = getRestClient().get().retrieve().toBodilessEntity();
 
 		assertThat(response.getStatusCode()).isEqualTo(HttpStatus.OK);
 		String id = extractSessionId(response.getHeaders());
 		assertThat(id).isNotNull();
 
 		// Second request: invalidates session
-		URI uri = URI.create("http://localhost:" + this.port + "/?invalidate");
-		request = RequestEntity.get(uri).header("Cookie", "SESSION=" + id).build();
-		response = this.restTemplate.exchange(request, Void.class);
+		response = getRestClient().get().uri("/?invalidate").cookie("SESSION", id).retrieve().toBodilessEntity();
 
 		assertThat(response.getStatusCode()).isEqualTo(HttpStatus.OK);
 		String value = response.getHeaders().getFirst("Set-Cookie");
@@ -205,10 +186,6 @@ class WebSessionIntegrationTests extends AbstractHttpHandlerIntegrationTests {
 		return null;
 	}
 
-	private URI createUri() {
-		return URI.create("http://localhost:" + this.port + "/");
-	}
-
 
 	private static class TestWebHandler implements WebHandler {
 

spring-web/src/testFixtures/java/org/springframework/web/testfixture/http/server/reactive/bootstrap/AbstractHttpHandlerIntegrationTests.java

@@ -36,6 +36,7 @@ import reactor.core.publisher.Flux;
 import org.springframework.http.server.reactive.HttpHandler;
 import org.springframework.util.StringUtils;
 import org.springframework.web.client.HttpServerErrorException;
+import org.springframework.web.client.RestClient;
 
 import static org.junit.jupiter.params.provider.Arguments.argumentSet;
 
@@ -75,6 +76,8 @@ public abstract class AbstractHttpHandlerIntegrationTests {
 
 	protected int port;
 
+	private RestClient restClient;
+
 
 	protected void startServer(HttpServer httpServer) throws Exception {
 		this.server = httpServer;
@@ -84,6 +87,7 @@ public abstract class AbstractHttpHandlerIntegrationTests {
 
 		// Set dynamically chosen port
 		this.port = this.server.getPort();
+		onServerStart(this.server.getPort());
 	}
 
 	@AfterEach
@@ -97,6 +101,18 @@ public abstract class AbstractHttpHandlerIntegrationTests {
 
 	protected abstract HttpHandler createHttpHandler();
 
+	protected void onServerStart(int port) {
+		this.restClient = initRestClient(RestClient.builder().baseUrl("http://localhost:" + this.port));
+	}
+
+	protected RestClient initRestClient(RestClient.Builder builder) {
+		return builder.build();
+	}
+
+	protected RestClient getRestClient() {
+		return this.restClient;
+	}
+
 
 	/**
 	 * Return an interval stream of N number of ticks and buffer the emissions

spring-webflux/src/test/java/org/springframework/web/reactive/function/server/DispatcherHandlerIntegrationTests.java

@@ -29,7 +29,6 @@ import org.springframework.context.annotation.AnnotationConfigApplicationContext
 import org.springframework.context.annotation.Bean;
 import org.springframework.context.annotation.Configuration;
 import org.springframework.core.ParameterizedTypeReference;
-import org.springframework.http.HttpMethod;
 import org.springframework.http.HttpStatus;
 import org.springframework.http.MediaType;
 import org.springframework.http.ResponseEntity;
@@ -37,7 +36,6 @@ import org.springframework.http.server.reactive.HttpHandler;
 import org.springframework.stereotype.Controller;
 import org.springframework.web.bind.annotation.RequestMapping;
 import org.springframework.web.bind.annotation.ResponseBody;
-import org.springframework.web.client.RestTemplate;
 import org.springframework.web.reactive.DispatcherHandler;
 import org.springframework.web.reactive.HandlerMapping;
 import org.springframework.web.reactive.config.EnableWebFlux;
@@ -60,8 +58,6 @@ import static org.springframework.web.reactive.function.server.RouterFunctions.r
  */
 class DispatcherHandlerIntegrationTests extends AbstractHttpHandlerIntegrationTests {
 
-	private final RestTemplate restTemplate = new RestTemplate();
-
 
 	@Override
 	protected HttpHandler createHttpHandler() {
@@ -76,8 +72,8 @@ class DispatcherHandlerIntegrationTests extends AbstractHttpHandlerIntegrationTe
 	void mono(HttpServer httpServer) throws Exception {
 		startServer(httpServer);
 
-		ResponseEntity<Person> result =
-				this.restTemplate.getForEntity("http://localhost:" + this.port + "/mono", Person.class);
+		ResponseEntity<Person> result = getRestClient().get().uri("http://localhost:" + this.port + "/mono")
+				.retrieve().toEntity(Person.class);
 
 		assertThat(result.getStatusCode()).isEqualTo(HttpStatus.OK);
 		assertThat(result.getBody().getName()).isEqualTo("John");
@@ -87,10 +83,8 @@ class DispatcherHandlerIntegrationTests extends AbstractHttpHandlerIntegrationTe
 	void flux(HttpServer httpServer) throws Exception {
 		startServer(httpServer);
 
-		ParameterizedTypeReference<List<Person>> reference = new ParameterizedTypeReference<>() {};
-		ResponseEntity<List<Person>> result =
-				this.restTemplate
-						.exchange("http://localhost:" + this.port + "/flux", HttpMethod.GET, null, reference);
+		ResponseEntity<List<Person>> result = getRestClient().get().uri("http://localhost:" + this.port + "/flux")
+				.retrieve().toEntity(new ParameterizedTypeReference<>() {});
 
 		assertThat(result.getStatusCode()).isEqualTo(HttpStatus.OK);
 		List<Person> body = result.getBody();
@@ -103,8 +97,8 @@ class DispatcherHandlerIntegrationTests extends AbstractHttpHandlerIntegrationTe
 	void controller(HttpServer httpServer) throws Exception {
 		startServer(httpServer);
 
-		ResponseEntity<Person> result =
-				this.restTemplate.getForEntity("http://localhost:" + this.port + "/controller", Person.class);
+		ResponseEntity<Person> result = getRestClient().get().uri("http://localhost:" + this.port + "/controller")
+				.retrieve().toEntity(Person.class);
 
 		assertThat(result.getStatusCode()).isEqualTo(HttpStatus.OK);
 		assertThat(result.getBody().getName()).isEqualTo("John");
@@ -114,9 +108,8 @@ class DispatcherHandlerIntegrationTests extends AbstractHttpHandlerIntegrationTe
 	void attributes(HttpServer httpServer) throws Exception {
 		startServer(httpServer);
 
-		ResponseEntity<String> result =
-				this.restTemplate
-						.getForEntity("http://localhost:" + this.port + "/attributes/bar", String.class);
+		ResponseEntity<String> result = getRestClient().get().uri("http://localhost:" + this.port + "/attributes/bar")
+				.retrieve().toEntity(String.class);
 
 		assertThat(result.getStatusCode()).isEqualTo(HttpStatus.OK);
 	}
@@ -125,8 +118,8 @@ class DispatcherHandlerIntegrationTests extends AbstractHttpHandlerIntegrationTe
 	void nested(HttpServer httpServer) throws Exception {
 		startServer(httpServer);
 
-		ResponseEntity<String> result = this.restTemplate
-				.getForEntity("http://localhost:" + this.port + "/foo/bar", String.class);
+		ResponseEntity<String> result = getRestClient().get().uri("http://localhost:" + this.port + "/foo/bar")
+				.retrieve().toEntity(String.class);
 
 		assertThat(result.getStatusCode()).isEqualTo(HttpStatus.OK);
 	}

spring-webflux/src/test/java/org/springframework/web/reactive/function/server/NestedRouteIntegrationTests.java

@@ -25,7 +25,6 @@ import reactor.core.publisher.Mono;
 import org.springframework.http.HttpMethod;
 import org.springframework.http.HttpStatus;
 import org.springframework.http.ResponseEntity;
-import org.springframework.web.client.RestTemplate;
 import org.springframework.web.testfixture.http.server.reactive.bootstrap.HttpServer;
 import org.springframework.web.util.pattern.PathPattern;
 
@@ -42,8 +41,6 @@ import static org.springframework.web.reactive.function.server.RouterFunctions.r
  */
 class NestedRouteIntegrationTests extends AbstractRouterFunctionIntegrationTests {
 
-	private final RestTemplate restTemplate = new RestTemplate();
-
 
 	@Override
 	protected RouterFunction<?> routerFunction() {
@@ -64,8 +61,8 @@ class NestedRouteIntegrationTests extends AbstractRouterFunctionIntegrationTests
 	void bar(HttpServer httpServer) throws Exception {
 		startServer(httpServer);
 
-		ResponseEntity<String> result =
-				restTemplate.getForEntity("http://localhost:" + port + "/foo/bar", String.class);
+		ResponseEntity<String> result = getRestClient().get().uri("http://localhost:" + port + "/foo/bar")
+				.retrieve().toEntity(String.class);
 
 		assertThat(result.getStatusCode()).isEqualTo(HttpStatus.OK);
 		assertThat(result.getBody()).isEqualTo("/foo/bar");
@@ -75,8 +72,8 @@ class NestedRouteIntegrationTests extends AbstractRouterFunctionIntegrationTests
 	void baz(HttpServer httpServer) throws Exception {
 		startServer(httpServer);
 
-		ResponseEntity<String> result =
-				restTemplate.getForEntity("http://localhost:" + port + "/foo/baz", String.class);
+		ResponseEntity<String> result = getRestClient().get().uri("http://localhost:" + port + "/foo/baz")
+				.retrieve().toEntity(String.class);
 
 		assertThat(result.getStatusCode()).isEqualTo(HttpStatus.OK);
 		assertThat(result.getBody()).isEqualTo("/foo/baz");
@@ -86,8 +83,8 @@ class NestedRouteIntegrationTests extends AbstractRouterFunctionIntegrationTests
 	void variables(HttpServer httpServer) throws Exception {
 		startServer(httpServer);
 
-		ResponseEntity<String> result =
-				restTemplate.getForEntity("http://localhost:" + port + "/1/2/3", String.class);
+		ResponseEntity<String> result = getRestClient().get().uri("http://localhost:" + port + "/1/2/3")
+				.retrieve().toEntity(String.class);
 
 		assertThat(result.getStatusCode()).isEqualTo(HttpStatus.OK);
 		String body = result.getBody();
@@ -102,8 +99,8 @@ class NestedRouteIntegrationTests extends AbstractRouterFunctionIntegrationTests
 	void parentVariables(HttpServer httpServer) throws Exception {
 		startServer(httpServer);
 
-		ResponseEntity<String> result =
-				restTemplate.getForEntity("http://localhost:" + port + "/1/bar", String.class);
+		ResponseEntity<String> result = getRestClient().get().uri("http://localhost:" + port + "/1/bar")
+				.retrieve().toEntity(String.class);
 
 		assertThat(result.getStatusCode()).isEqualTo(HttpStatus.OK);
 		assertThat(result.getBody()).isEqualTo("/{foo}/bar\n{foo=1}");
@@ -115,8 +112,8 @@ class NestedRouteIntegrationTests extends AbstractRouterFunctionIntegrationTests
 	void removeFailedNestedPathVariables(HttpServer httpServer) throws Exception {
 		startServer(httpServer);
 
-		ResponseEntity<String> result =
-				restTemplate.getForEntity("http://localhost:" + port + "/qux/quux", String.class);
+		ResponseEntity<String> result = getRestClient().get().uri("http://localhost:" + port + "/qux/quux")
+				.retrieve().toEntity(String.class);
 
 		assertThat(result.getStatusCode()).isEqualTo(HttpStatus.OK);
 		assertThat(result.getBody()).isEqualTo("/{qux}/quux\n{qux=qux}");
@@ -128,8 +125,8 @@ class NestedRouteIntegrationTests extends AbstractRouterFunctionIntegrationTests
 	void removeFailedPathVariablesAnd(HttpServer httpServer) throws Exception {
 		startServer(httpServer);
 
-		ResponseEntity<String> result =
-				restTemplate.postForEntity("http://localhost:" + port + "/qux/quux", "", String.class);
+		ResponseEntity<String> result = getRestClient().post().uri("http://localhost:" + port + "/qux/quux")
+				.retrieve().toEntity(String.class);
 
 		assertThat(result.getStatusCode()).isEqualTo(HttpStatus.OK);
 		assertThat(result.getBody()).isEqualTo("{}");

spring-webflux/src/test/java/org/springframework/web/reactive/function/server/PublisherHandlerFunctionIntegrationTests.java

@@ -16,7 +16,6 @@
 
 package org.springframework.web.reactive.function.server;
 
-import java.net.URI;
 import java.util.List;
 import java.util.Objects;
 
@@ -25,11 +24,8 @@ import reactor.core.publisher.Flux;
 import reactor.core.publisher.Mono;
 
 import org.springframework.core.ParameterizedTypeReference;
-import org.springframework.http.HttpMethod;
 import org.springframework.http.HttpStatus;
-import org.springframework.http.RequestEntity;
 import org.springframework.http.ResponseEntity;
-import org.springframework.web.client.RestTemplate;
 import org.springframework.web.testfixture.http.server.reactive.bootstrap.HttpServer;
 
 import static org.assertj.core.api.Assertions.assertThat;
@@ -44,8 +40,6 @@ import static org.springframework.web.reactive.function.server.RouterFunctions.r
  */
 class PublisherHandlerFunctionIntegrationTests extends AbstractRouterFunctionIntegrationTests {
 
-	private final RestTemplate restTemplate = new RestTemplate();
-
 
 	@Override
 	protected RouterFunction<?> routerFunction() {
@@ -55,13 +49,11 @@ class PublisherHandlerFunctionIntegrationTests extends AbstractRouterFunctionInt
 				.and(route(GET("/flux"), personHandler::flux));
 	}
 
-
 	@ParameterizedHttpServerTest
 	void mono(HttpServer httpServer) throws Exception {
 		startServer(httpServer);
 
-		ResponseEntity<Person> result =
-				restTemplate.getForEntity("http://localhost:" + super.port + "/mono", Person.class);
+		ResponseEntity<Person> result = getRestClient().get().uri("/mono").retrieve().toEntity(Person.class);
 
 		assertThat(result.getStatusCode()).isEqualTo(HttpStatus.OK);
 		assertThat(result.getBody().getName()).isEqualTo("John");
@@ -71,9 +63,8 @@ class PublisherHandlerFunctionIntegrationTests extends AbstractRouterFunctionInt
 	void flux(HttpServer httpServer) throws Exception {
 		startServer(httpServer);
 
-		ParameterizedTypeReference<List<Person>> reference = new ParameterizedTypeReference<>() {};
-		ResponseEntity<List<Person>> result =
-				restTemplate.exchange("http://localhost:" + super.port + "/flux", HttpMethod.GET, null, reference);
+		ResponseEntity<List<Person>> result = getRestClient().get().uri("/flux").retrieve()
+				.toEntity(new ParameterizedTypeReference<>() {});
 
 		assertThat(result.getStatusCode()).isEqualTo(HttpStatus.OK);
 		List<Person> body = result.getBody();
@@ -86,10 +77,8 @@ class PublisherHandlerFunctionIntegrationTests extends AbstractRouterFunctionInt
 	void postMono(HttpServer httpServer) throws Exception {
 		startServer(httpServer);
 
-		URI uri = URI.create("http://localhost:" + super.port + "/mono");
 		Person person = new Person("Jack");
-		RequestEntity<Person> requestEntity = RequestEntity.post(uri).body(person);
-		ResponseEntity<Person> result = restTemplate.exchange(requestEntity, Person.class);
+		ResponseEntity<Person> result = getRestClient().post().uri("/mono").body(person).retrieve().toEntity(Person.class);
 
 		assertThat(result.getStatusCode()).isEqualTo(HttpStatus.OK);
 		assertThat(result.getBody().getName()).isEqualTo("Jack");

spring-webflux/src/test/java/org/springframework/web/reactive/function/server/RenderingResponseIntegrationTests.java

@@ -31,7 +31,6 @@ import org.springframework.http.MediaType;
 import org.springframework.http.ResponseEntity;
 import org.springframework.http.server.reactive.ServerHttpResponse;
 import org.springframework.util.CollectionUtils;
-import org.springframework.web.client.RestTemplate;
 import org.springframework.web.reactive.result.view.View;
 import org.springframework.web.reactive.result.view.ViewResolver;
 import org.springframework.web.server.ServerWebExchange;
@@ -48,8 +47,6 @@ import static org.springframework.web.reactive.function.server.RouterFunctions.r
  */
 class RenderingResponseIntegrationTests extends AbstractRouterFunctionIntegrationTests {
 
-	private final RestTemplate restTemplate = new RestTemplate();
-
 
 	@Override
 	protected RouterFunction<?> routerFunction() {
@@ -76,8 +73,7 @@ class RenderingResponseIntegrationTests extends AbstractRouterFunctionIntegratio
 	void normal(HttpServer httpServer) throws Exception {
 		startServer(httpServer);
 
-		ResponseEntity<String> result =
-				restTemplate.getForEntity("http://localhost:" + port + "/normal", String.class);
+		ResponseEntity<String> result = getRestClient().get().uri("/normal").retrieve().toEntity(String.class);
 
 		assertThat(result.getStatusCode()).isEqualTo(HttpStatus.OK);
 		Map<String, String> body = parseBody(result.getBody());
@@ -90,8 +86,7 @@ class RenderingResponseIntegrationTests extends AbstractRouterFunctionIntegratio
 	void filter(HttpServer httpServer) throws Exception {
 		startServer(httpServer);
 
-		ResponseEntity<String> result =
-				restTemplate.getForEntity("http://localhost:" + port + "/filter", String.class);
+		ResponseEntity<String> result = getRestClient().get().uri("/filter").retrieve().toEntity(String.class);
 
 		assertThat(result.getStatusCode()).isEqualTo(HttpStatus.OK);
 		Map<String, String> body = parseBody(result.getBody());

spring-webflux/src/test/java/org/springframework/web/reactive/result/SimpleUrlHandlerMappingIntegrationTests.java

@@ -16,7 +16,6 @@
 
 package org.springframework.web.reactive.result;
 
-import java.net.URI;
 import java.nio.charset.StandardCharsets;
 import java.util.HashMap;
 import java.util.Map;
@@ -31,11 +30,9 @@ import org.springframework.core.io.buffer.DataBuffer;
 import org.springframework.core.io.buffer.DefaultDataBuffer;
 import org.springframework.core.io.buffer.DefaultDataBufferFactory;
 import org.springframework.http.HttpStatus;
-import org.springframework.http.RequestEntity;
 import org.springframework.http.ResponseEntity;
 import org.springframework.http.server.reactive.HttpHandler;
 import org.springframework.web.client.HttpClientErrorException;
-import org.springframework.web.client.RestTemplate;
 import org.springframework.web.reactive.DispatcherHandler;
 import org.springframework.web.reactive.handler.SimpleUrlHandlerMapping;
 import org.springframework.web.server.WebHandler;
@@ -54,6 +51,7 @@ import static org.assertj.core.api.Assertions.assertThat;
  */
 class SimpleUrlHandlerMappingIntegrationTests extends AbstractHttpHandlerIntegrationTests {
 
+
 	@Override
 	protected HttpHandler createHttpHandler() {
 		AnnotationConfigApplicationContext wac = new AnnotationConfigApplicationContext(WebConfig.class);
@@ -63,15 +61,12 @@ class SimpleUrlHandlerMappingIntegrationTests extends AbstractHttpHandlerIntegra
 				.build();
 	}
 
-
 	@ParameterizedHttpServerTest
 	void requestToFooHandler(HttpServer httpServer) throws Exception {
 		startServer(httpServer);
 
-		URI url = URI.create("http://localhost:" + this.port + "/foo");
-		RequestEntity<Void> request = RequestEntity.get(url).build();
-		@SuppressWarnings("resource")
-		ResponseEntity<byte[]> response = new RestTemplate().exchange(request, byte[].class);
+		ResponseEntity<byte[]> response = getRestClient().get().uri("http://localhost:" + this.port + "/foo")
+				.retrieve().toEntity(byte[].class);
 
 		assertThat(response.getStatusCode()).isEqualTo(HttpStatus.OK);
 		assertThat(response.getBody()).isEqualTo("foo".getBytes(StandardCharsets.UTF_8));
@@ -81,10 +76,8 @@ class SimpleUrlHandlerMappingIntegrationTests extends AbstractHttpHandlerIntegra
 	public void requestToBarHandler(HttpServer httpServer) throws Exception {
 		startServer(httpServer);
 
-		URI url = URI.create("http://localhost:" + this.port + "/bar");
-		RequestEntity<Void> request = RequestEntity.get(url).build();
-		@SuppressWarnings("resource")
-		ResponseEntity<byte[]> response = new RestTemplate().exchange(request, byte[].class);
+		ResponseEntity<byte[]> response = getRestClient().get().uri("http://localhost:" + this.port + "/bar")
+				.retrieve().toEntity(byte[].class);
 
 		assertThat(response.getStatusCode()).isEqualTo(HttpStatus.OK);
 		assertThat(response.getBody()).isEqualTo("bar".getBytes(StandardCharsets.UTF_8));
@@ -94,24 +87,19 @@ class SimpleUrlHandlerMappingIntegrationTests extends AbstractHttpHandlerIntegra
 	void requestToHeaderSettingHandler(HttpServer httpServer) throws Exception {
 		startServer(httpServer);
 
-		URI url = URI.create("http://localhost:" + this.port + "/header");
-		RequestEntity<Void> request = RequestEntity.get(url).build();
-		@SuppressWarnings("resource")
-		ResponseEntity<byte[]> response = new RestTemplate().exchange(request, byte[].class);
+		ResponseEntity<byte[]> response = getRestClient().get().uri("http://localhost:" + this.port + "/header")
+				.retrieve().toEntity(byte[].class);
 
 		assertThat(response.getStatusCode()).isEqualTo(HttpStatus.OK);
 		assertThat(response.getHeaders().getFirst("foo")).isEqualTo("bar");
 	}
 
 	@ParameterizedHttpServerTest
-	@SuppressWarnings("resource")
 	void handlerNotFound(HttpServer httpServer) throws Exception {
 		startServer(httpServer);
 
-		URI url = URI.create("http://localhost:" + this.port + "/oops");
-		RequestEntity<Void> request = RequestEntity.get(url).build();
 		try {
-			new RestTemplate().exchange(request, byte[].class);
+			getRestClient().get().uri("http://localhost:" + this.port + "/oops").retrieve().toEntity(byte[].class);
 		}
 		catch (HttpClientErrorException ex) {
 			assertThat(ex.getStatusCode()).isEqualTo(HttpStatus.NOT_FOUND);

spring-webflux/src/test/java/org/springframework/web/reactive/result/method/annotation/AbstractRequestMappingIntegrationTests.java

@@ -17,18 +17,14 @@
 package org.springframework.web.reactive.result.method.annotation;
 
 import java.net.URI;
-import java.util.Collections;
-import java.util.List;
-import java.util.Map;
 
 import org.springframework.context.ApplicationContext;
 import org.springframework.core.ParameterizedTypeReference;
 import org.springframework.http.HttpHeaders;
 import org.springframework.http.MediaType;
-import org.springframework.http.RequestEntity;
 import org.springframework.http.ResponseEntity;
 import org.springframework.http.server.reactive.HttpHandler;
-import org.springframework.web.client.RestTemplate;
+import org.springframework.web.client.RestClient;
 import org.springframework.web.server.adapter.WebHttpHandlerBuilder;
 import org.springframework.web.testfixture.http.server.reactive.bootstrap.AbstractHttpHandlerIntegrationTests;
 
@@ -39,102 +35,74 @@ import org.springframework.web.testfixture.http.server.reactive.bootstrap.Abstra
  */
 public abstract class AbstractRequestMappingIntegrationTests extends AbstractHttpHandlerIntegrationTests {
 
-	private RestTemplate restTemplate = new RestTemplate();
-
 	private ApplicationContext applicationContext;
 
 
 	@Override
 	protected HttpHandler createHttpHandler() {
-		this.restTemplate = initRestTemplate();
 		this.applicationContext = initApplicationContext();
 		return WebHttpHandlerBuilder.applicationContext(this.applicationContext).build();
 	}
 
 	protected abstract ApplicationContext initApplicationContext();
 
-	protected RestTemplate initRestTemplate() {
-		return new RestTemplate();
-	}
-
 	protected ApplicationContext getApplicationContext() {
 		return this.applicationContext;
 	}
 
-	protected RestTemplate getRestTemplate() {
-		return this.restTemplate;
-	}
 
 
 	<T> ResponseEntity<T> performGet(String url, MediaType out, Class<T> type) {
-		HttpHeaders headers = new HttpHeaders();
-		headers.setAccept(Collections.singletonList(out));
-		return getRestTemplate().exchange(prepareGet(url, headers), type);
+		return getRestClient()
+				.get().uri(URI.create(url)).accept(out)
+				.retrieve()
+				.toEntity(type);
 	}
 
 	<T> ResponseEntity<T> performGet(String url, HttpHeaders headers, Class<T> type) {
-		return getRestTemplate().exchange(prepareGet(url, headers), type);
+		return getRestClient()
+				.get().uri(URI.create(url)).headers(httpHeaders -> httpHeaders.putAll(headers))
+				.retrieve()
+				.toEntity(type);
 	}
 
 	<T> ResponseEntity<T> performGet(String url, MediaType out, ParameterizedTypeReference<T> type) {
-		HttpHeaders headers = new HttpHeaders();
-		headers.setAccept(Collections.singletonList(out));
-		return this.restTemplate.exchange(prepareGet(url, headers), type);
+		return getRestClient()
+				.get().uri(URI.create(url)).accept(out)
+				.retrieve()
+				.toEntity(type);
 	}
 
 	<T> ResponseEntity<T> performOptions(String url, HttpHeaders headers, Class<T> type) {
-		return getRestTemplate().exchange(prepareOptions(url, headers), type);
+		return getRestClient()
+				.options().uri(URI.create(url)).headers(httpHeaders -> httpHeaders.putAll(headers))
+				.retrieve()
+				.toEntity(type);
 	}
 
 	<T> ResponseEntity<T> performPost(String url, MediaType in, Object body, MediaType out, Class<T> type) {
-		HttpHeaders headers = new HttpHeaders();
-		headers.setContentType(in);
-		if (out != null) {
-			headers.setAccept(Collections.singletonList(out));
+		RestClient.RequestBodySpec bodySpec = getRestClient()
+				.post().uri(URI.create(url)).accept(out).contentType(in);
+		if (body != null) {
+			bodySpec.body(body);
 		}
-		return getRestTemplate().exchange(preparePost(url, headers, body), type);
+		return bodySpec.retrieve().toEntity(type);
 	}
 
 	<T> ResponseEntity<T> performPost(String url, HttpHeaders headers, Object body, Class<T> type) {
-		return getRestTemplate().exchange(preparePost(url, headers, body), type);
+		RestClient.RequestBodySpec bodySpec = getRestClient()
+				.post().uri(URI.create(url)).headers(httpHeaders -> httpHeaders.putAll(headers));
+		if (body != null) {
+			bodySpec.body(body);
+		}
+		return bodySpec.retrieve().toEntity(type);
 	}
 
 	<T> ResponseEntity<T> performPost(String url, MediaType in, Object body, MediaType out, ParameterizedTypeReference<T> type) {
-		HttpHeaders headers = new HttpHeaders();
-		headers.setContentType(in);
-		if (out != null) {
-			headers.setAccept(Collections.singletonList(out));
-		}
-		return getRestTemplate().exchange(preparePost(url, headers, body), type);
-	}
-
-	private RequestEntity<Void> prepareGet(String url, HttpHeaders headers) {
-		URI uri = URI.create("http://localhost:" + this.port + url);
-		RequestEntity.HeadersBuilder<?> builder = RequestEntity.get(uri);
-		addHeaders(builder, headers);
-		return builder.build();
-	}
-
-	private RequestEntity<Void> prepareOptions(String url, HttpHeaders headers) {
-		URI uri = URI.create("http://localhost:" + this.port + url);
-		RequestEntity.HeadersBuilder<?> builder = RequestEntity.options(uri);
-		addHeaders(builder, headers);
-		return builder.build();
-	}
-
-	private void addHeaders(RequestEntity.HeadersBuilder<?> builder, HttpHeaders headers) {
-		for (Map.Entry<String, List<String>> entry : headers.headerSet()) {
-			for (String value : entry.getValue()) {
-				builder.header(entry.getKey(), value);
-			}
-		}
-	}
-
-	private RequestEntity<?> preparePost(String url, HttpHeaders headers, Object body) {
-		URI uri = URI.create("http://localhost:" + this.port + url);
-		RequestEntity.BodyBuilder builder = RequestEntity.post(uri);
-		addHeaders(builder, headers);
-		return builder.body(body);
+		return getRestClient()
+				.post().uri(URI.create(url)).accept(out).contentType(in).body(body)
+				.retrieve()
+				.toEntity(type);
 	}
 
 }

spring-webflux/src/test/java/org/springframework/web/reactive/result/method/annotation/ContextPathIntegrationTests.java

@@ -30,7 +30,7 @@ import org.springframework.http.server.reactive.HttpHandler;
 import org.springframework.http.server.reactive.ServerHttpRequest;
 import org.springframework.web.bind.annotation.GetMapping;
 import org.springframework.web.bind.annotation.RestController;
-import org.springframework.web.client.RestTemplate;
+import org.springframework.web.client.RestClient;
 import org.springframework.web.reactive.config.EnableWebFlux;
 import org.springframework.web.server.adapter.WebHttpHandlerBuilder;
 import org.springframework.web.testfixture.http.server.reactive.bootstrap.AbstractHttpServer;
@@ -73,16 +73,13 @@ class ContextPathIntegrationTests {
 		server.start();
 
 		try {
-			RestTemplate restTemplate = new RestTemplate();
-			String actual;
+			RestClient restClient = RestClient.create("http://localhost:" + server.getPort());
 
-			String url = "http://localhost:" + server.getPort() + "/webApp1/test";
-			actual = restTemplate.getForObject(url, String.class);
-			assertThat(actual).isEqualTo("Tested in /webApp1");
+			assertThat(restClient.get().uri("/webApp1/test").retrieve().body(String.class))
+					.isEqualTo("Tested in /webApp1");
 
-			url = "http://localhost:" + server.getPort() + "/webApp2/test";
-			actual = restTemplate.getForObject(url, String.class);
-			assertThat(actual).isEqualTo("Tested in /webApp2");
+			assertThat(restClient.get().uri("/webApp2/test").retrieve().body(String.class))
+					.isEqualTo("Tested in /webApp2");
 		}
 		finally {
 			server.stop();
@@ -104,9 +101,9 @@ class ContextPathIntegrationTests {
 		server.start();
 
 		try {
-			String url = "http://localhost:" + server.getPort() + "/app/api/test";
-			String actual = new RestTemplate().getForObject(url, String.class);
-			assertThat(actual).isEqualTo("Tested in /app/api");
+			RestClient restClient = RestClient.create("http://localhost:" + server.getPort());
+			assertThat(restClient.get().uri("/app/api/test").retrieve().body(String.class))
+					.isEqualTo("Tested in /app/api");
 		}
 		finally {
 			server.stop();

spring-webflux/src/test/java/org/springframework/web/reactive/result/method/annotation/CrossOriginAnnotationIntegrationTests.java

@@ -35,7 +35,7 @@ import org.springframework.web.bind.annotation.PostMapping;
 import org.springframework.web.bind.annotation.RequestMapping;
 import org.springframework.web.bind.annotation.RequestMethod;
 import org.springframework.web.bind.annotation.RestController;
-import org.springframework.web.client.RestTemplate;
+import org.springframework.web.client.RestClient;
 import org.springframework.web.reactive.config.EnableWebFlux;
 import org.springframework.web.testfixture.http.server.reactive.bootstrap.HttpServer;
 
@@ -73,10 +73,11 @@ class CrossOriginAnnotationIntegrationTests extends AbstractRequestMappingIntegr
 		return context;
 	}
 
+
 	@Override
-	protected RestTemplate initRestTemplate() {
+	protected RestClient initRestClient(RestClient.Builder builder) {
 		// JDK default HTTP client disallowed headers like Origin
-		return new RestTemplate(new HttpComponentsClientHttpRequestFactory());
+		return builder.requestFactory(new HttpComponentsClientHttpRequestFactory()).build();
 	}
 
 

spring-webflux/src/test/java/org/springframework/web/reactive/result/method/annotation/GlobalCorsConfigIntegrationTests.java

@@ -29,7 +29,7 @@ import org.springframework.http.client.HttpComponentsClientHttpRequestFactory;
 import org.springframework.web.bind.annotation.GetMapping;
 import org.springframework.web.bind.annotation.RestController;
 import org.springframework.web.client.HttpClientErrorException;
-import org.springframework.web.client.RestTemplate;
+import org.springframework.web.client.RestClient;
 import org.springframework.web.reactive.config.CorsRegistry;
 import org.springframework.web.reactive.config.WebFluxConfigurationSupport;
 import org.springframework.web.testfixture.http.server.reactive.bootstrap.HttpServer;
@@ -63,9 +63,9 @@ class GlobalCorsConfigIntegrationTests extends AbstractRequestMappingIntegration
 	}
 
 	@Override
-	protected RestTemplate initRestTemplate() {
+	protected RestClient initRestClient(RestClient.Builder builder) {
 		// JDK default HTTP client disallowed headers like Origin
-		return new RestTemplate(new HttpComponentsClientHttpRequestFactory());
+		return builder.requestFactory(new HttpComponentsClientHttpRequestFactory()).build();
 	}
 
 

spring-webflux/src/test/java/org/springframework/web/reactive/result/method/annotation/RequestMappingIntegrationTests.java

@@ -16,7 +16,6 @@
 
 package org.springframework.web.reactive.result.method.annotation;
 
-import java.net.URI;
 import java.time.Duration;
 import java.util.concurrent.atomic.AtomicInteger;
 import java.util.function.Predicate;
@@ -31,7 +30,6 @@ import org.springframework.context.annotation.Configuration;
 import org.springframework.core.ReactiveAdapterRegistry;
 import org.springframework.core.task.AsyncTaskExecutor;
 import org.springframework.http.HttpHeaders;
-import org.springframework.http.RequestEntity;
 import org.springframework.http.ResponseEntity;
 import org.springframework.http.server.reactive.ServerHttpRequest;
 import org.springframework.web.bind.annotation.GetMapping;
@@ -75,11 +73,8 @@ class RequestMappingIntegrationTests extends AbstractRequestMappingIntegrationTe
 	void emptyMapping(HttpServer httpServer) throws Exception {
 		startServer(httpServer);
 
-		String url = "http://localhost:" + this.port;
-		assertThat(getRestTemplate().getForObject(url, String.class)).isEqualTo("root");
-
-		url += "/";
-		assertThat(getRestTemplate().getForObject(url, String.class)).isEqualTo("root");
+		assertThat(getRestClient().get().retrieve().body(String.class)).isEqualTo("root");
+		assertThat(getRestClient().get().uri("/").retrieve().body(String.class)).isEqualTo("root");
 
 		assertThat(getApplicationContext().getBean(TestExecutor.class).invocationCount.get()).isEqualTo(4);
 		assertThat(getApplicationContext().getBean(TestPredicate.class).invocationCount.get()).isEqualTo(4);
@@ -89,9 +84,8 @@ class RequestMappingIntegrationTests extends AbstractRequestMappingIntegrationTe
 	void httpHead(HttpServer httpServer) throws Exception {
 		startServer(httpServer);
 
-		String url = "http://localhost:" + this.port + "/text";
-		HttpHeaders headers = getRestTemplate().headForHeaders(url);
-		String contentType = headers.getFirst("Content-Type");
+		ResponseEntity<Void> response = getRestClient().head().uri("/text").retrieve().toBodilessEntity();
+		String contentType = response.getHeaders().getFirst("Content-Type");
 		assertThat(contentType).isNotNull();
 	}
 
@@ -102,11 +96,11 @@ class RequestMappingIntegrationTests extends AbstractRequestMappingIntegrationTe
 		// One integration test to verify triggering of Forwarded header support.
 		// More fine-grained tests in ForwardedHeaderTransformerTests.
 
-		RequestEntity<Void> request = RequestEntity
-				.get(URI.create("http://localhost:" + this.port + "/uri"))
+		ResponseEntity<String> entity = getRestClient().get().uri("/uri")
 				.header("Forwarded", "host=84.198.58.199;proto=https")
-				.build();
-		ResponseEntity<String> entity = getRestTemplate().exchange(request, String.class);
+				.retrieve()
+				.toEntity(String.class);
+
 		assertThat(entity.getBody()).isEqualTo("https://84.198.58.199/uri");
 	}
 

spring-webflux/src/test/java/org/springframework/web/reactive/result/method/annotation/RequestMappingMessageConversionIntegrationTests.java

@@ -366,7 +366,7 @@ class RequestMappingMessageConversionIntegrationTests extends AbstractRequestMap
 		startServer(httpServer);
 
 		ResponseEntity<Void> entity = performPost("/person-create/publisher", JSON,
-				asList(new Person("Robert"), new Person("Marie")), null, Void.class);
+				asList(new Person("Robert"), new Person("Marie")), MediaType.ALL, Void.class);
 
 		assertThat(entity.getStatusCode()).isEqualTo(HttpStatus.OK);
 		assertThat(getApplicationContext().getBean(PersonCreateController.class).persons).hasSize(2);
@@ -377,7 +377,7 @@ class RequestMappingMessageConversionIntegrationTests extends AbstractRequestMap
 		startServer(httpServer);
 
 		People people = new People(new Person("Robert"), new Person("Marie"));
-		ResponseEntity<Void> response = performPost("/person-create/publisher", APPLICATION_XML, people, null, Void.class);
+		ResponseEntity<Void> response = performPost("/person-create/publisher", APPLICATION_XML, people, MediaType.ALL, Void.class);
 
 		assertThat(response.getStatusCode()).isEqualTo(HttpStatus.OK);
 		assertThat(getApplicationContext().getBean(PersonCreateController.class).persons).hasSize(2);
@@ -388,7 +388,7 @@ class RequestMappingMessageConversionIntegrationTests extends AbstractRequestMap
 		startServer(httpServer);
 
 		ResponseEntity<Void> entity = performPost(
-				"/person-create/mono", JSON, new Person("Robert"), null, Void.class);
+				"/person-create/mono", JSON, new Person("Robert"), MediaType.ALL, Void.class);
 
 		assertThat(entity.getStatusCode()).isEqualTo(HttpStatus.OK);
 		assertThat(getApplicationContext().getBean(PersonCreateController.class).persons).hasSize(1);
@@ -399,7 +399,7 @@ class RequestMappingMessageConversionIntegrationTests extends AbstractRequestMap
 		startServer(httpServer);
 
 		ResponseEntity<Void> entity = performPost(
-				"/person-create/single", JSON, new Person("Robert"), null, Void.class);
+				"/person-create/single", JSON, new Person("Robert"), MediaType.ALL, Void.class);
 
 		assertThat(entity.getStatusCode()).isEqualTo(HttpStatus.OK);
 		assertThat(getApplicationContext().getBean(PersonCreateController.class).persons).hasSize(1);
@@ -410,7 +410,7 @@ class RequestMappingMessageConversionIntegrationTests extends AbstractRequestMap
 		startServer(httpServer);
 
 		ResponseEntity<Void> entity = performPost("/person-create/flux", JSON,
-				asList(new Person("Robert"), new Person("Marie")), null, Void.class);
+				asList(new Person("Robert"), new Person("Marie")), MediaType.ALL, Void.class);
 
 		assertThat(entity.getStatusCode()).isEqualTo(HttpStatus.OK);
 		assertThat(getApplicationContext().getBean(PersonCreateController.class).persons).hasSize(2);
@@ -421,7 +421,7 @@ class RequestMappingMessageConversionIntegrationTests extends AbstractRequestMap
 		startServer(httpServer);
 
 		People people = new People(new Person("Robert"), new Person("Marie"));
-		ResponseEntity<Void> response = performPost("/person-create/flux", APPLICATION_XML, people, null, Void.class);
+		ResponseEntity<Void> response = performPost("/person-create/flux", APPLICATION_XML, people, MediaType.ALL, Void.class);
 
 		assertThat(response.getStatusCode()).isEqualTo(HttpStatus.OK);
 		assertThat(getApplicationContext().getBean(PersonCreateController.class).persons).hasSize(2);
@@ -432,7 +432,7 @@ class RequestMappingMessageConversionIntegrationTests extends AbstractRequestMap
 		startServer(httpServer);
 
 		ResponseEntity<Void> entity = performPost("/person-create/observable", JSON,
-				asList(new Person("Robert"), new Person("Marie")), null, Void.class);
+				asList(new Person("Robert"), new Person("Marie")), MediaType.ALL, Void.class);
 
 		assertThat(entity.getStatusCode()).isEqualTo(HttpStatus.OK);
 		assertThat(getApplicationContext().getBean(PersonCreateController.class).persons).hasSize(2);
@@ -443,7 +443,7 @@ class RequestMappingMessageConversionIntegrationTests extends AbstractRequestMap
 		startServer(httpServer);
 
 		People people = new People(new Person("Robert"), new Person("Marie"));
-		ResponseEntity<Void> response = performPost("/person-create/observable", APPLICATION_XML, people, null, Void.class);
+		ResponseEntity<Void> response = performPost("/person-create/observable", APPLICATION_XML, people, MediaType.ALL, Void.class);
 
 		assertThat(response.getStatusCode()).isEqualTo(HttpStatus.OK);
 		assertThat(getApplicationContext().getBean(PersonCreateController.class).persons).hasSize(2);
@@ -454,7 +454,7 @@ class RequestMappingMessageConversionIntegrationTests extends AbstractRequestMap
 		startServer(httpServer);
 
 		ResponseEntity<Void> entity = performPost("/person-create/flowable", JSON,
-				asList(new Person("Robert"), new Person("Marie")), null, Void.class);
+				asList(new Person("Robert"), new Person("Marie")), MediaType.ALL, Void.class);
 
 		assertThat(entity.getStatusCode()).isEqualTo(HttpStatus.OK);
 		assertThat(getApplicationContext().getBean(PersonCreateController.class).persons).hasSize(2);
@@ -465,7 +465,7 @@ class RequestMappingMessageConversionIntegrationTests extends AbstractRequestMap
 		startServer(httpServer);
 
 		People people = new People(new Person("Robert"), new Person("Marie"));
-		ResponseEntity<Void> response = performPost("/person-create/flowable", APPLICATION_XML, people, null, Void.class);
+		ResponseEntity<Void> response = performPost("/person-create/flowable", APPLICATION_XML, people, MediaType.ALL, Void.class);
 
 		assertThat(response.getStatusCode()).isEqualTo(HttpStatus.OK);
 		assertThat(getApplicationContext().getBean(PersonCreateController.class).persons).hasSize(2);
@@ -474,7 +474,7 @@ class RequestMappingMessageConversionIntegrationTests extends AbstractRequestMap
 	@ParameterizedHttpServerTest // gh-23791
 	void personCreateViaDefaultMethodWithGenerics(HttpServer httpServer) throws Exception {
 		startServer(httpServer);
-		ResponseEntity<String> entity = performPost("/23791", JSON, new Person("Robert"), null, String.class);
+		ResponseEntity<String> entity = performPost("/23791", JSON, new Person("Robert"), MediaType.ALL, String.class);
 
 		assertThat(entity.getStatusCode()).isEqualTo(HttpStatus.OK);
 		assertThat(entity.getBody()).isEqualTo("Person");

spring-webflux/src/test/java/org/springframework/web/reactive/result/method/annotation/RequestMappingVersionIntegrationTests.java

@@ -22,7 +22,6 @@ import org.junit.jupiter.api.Test;
 
 import org.springframework.context.ApplicationContext;
 import org.springframework.context.annotation.AnnotationConfigApplicationContext;
-import org.springframework.http.RequestEntity;
 import org.springframework.http.ResponseEntity;
 import org.springframework.web.accept.SemanticApiVersionParser.Version;
 import org.springframework.web.bind.annotation.GetMapping;
@@ -77,18 +76,15 @@ class RequestMappingVersionIntegrationTests extends AbstractRequestMappingIntegr
 	@Test  // gh-36059
 	void staticResourceWithInvalidApiVersion() throws Exception {
 		startServer(new TomcatHttpServer());
-
-		String url = "http://localhost:" + this.port + "/cp/test/foo.css";
-		RequestEntity<Void> requestEntity = RequestEntity.get(url).header("API-Version", "Invalid").build();
-		ResponseEntity<String> entity = getRestTemplate().exchange(requestEntity, String.class);
+		ResponseEntity<String> entity = getRestClient().get().uri("/cp/test/foo.css")
+				.header("API-Version", "Invalid").retrieve().toEntity(String.class);
 
 		assertThat(entity.getBody()).isEqualTo("h1 { color:red; }");
 	}
 
 	private ResponseEntity<String> exchangeWithVersion(String version) {
-		String url = "http://localhost:" + this.port;
-		RequestEntity<Void> requestEntity = RequestEntity.get(url).header("API-Version", version).build();
-		return getRestTemplate().exchange(requestEntity, String.class);
+		return getRestClient().get().uri("/").header("API-Version", version)
+				.retrieve().toEntity(String.class);
 	}
 
 

spring-webflux/src/test/java/org/springframework/web/reactive/result/method/annotation/RequestMappingViewResolutionIntegrationTests.java

@@ -18,7 +18,6 @@ package org.springframework.web.reactive.result.method.annotation;
 
 import java.io.IOException;
 import java.net.HttpURLConnection;
-import java.net.URI;
 import java.util.Optional;
 
 import org.springframework.context.ApplicationContext;
@@ -28,13 +27,12 @@ import org.springframework.context.annotation.ComponentScan;
 import org.springframework.context.annotation.Configuration;
 import org.springframework.http.HttpStatus;
 import org.springframework.http.MediaType;
-import org.springframework.http.RequestEntity;
 import org.springframework.http.ResponseEntity;
 import org.springframework.http.client.SimpleClientHttpRequestFactory;
 import org.springframework.stereotype.Controller;
 import org.springframework.ui.Model;
 import org.springframework.web.bind.annotation.GetMapping;
-import org.springframework.web.client.RestTemplate;
+import org.springframework.web.client.RestClient;
 import org.springframework.web.reactive.config.EnableWebFlux;
 import org.springframework.web.reactive.config.ViewResolverRegistry;
 import org.springframework.web.reactive.config.WebFluxConfigurer;
@@ -69,9 +67,9 @@ class RequestMappingViewResolutionIntegrationTests extends AbstractRequestMappin
 	void etagCheckWithNotModifiedResponse(HttpServer httpServer) throws Exception {
 		startServer(httpServer);
 
-		URI uri = URI.create("http://localhost:" + this.port + "/html");
-		RequestEntity<Void> request = RequestEntity.get(uri).ifNoneMatch("\"deadb33f8badf00d\"").build();
-		ResponseEntity<String> response = getRestTemplate().exchange(request, String.class);
+		ResponseEntity<String> response = getRestClient().get().uri("/html")
+				.headers(headers -> headers.setIfNoneMatch("\"deadb33f8badf00d\""))
+				.retrieve().toEntity(String.class);
 
 		assertThat(response.getStatusCode()).isEqualTo(HttpStatus.NOT_MODIFIED);
 		assertThat(response.getBody()).isNull();
@@ -89,9 +87,10 @@ class RequestMappingViewResolutionIntegrationTests extends AbstractRequestMappin
 			}
 		};
 
-		URI uri = URI.create("http://localhost:" + this.port + "/redirect");
-		RequestEntity<Void> request = RequestEntity.get(uri).accept(MediaType.ALL).build();
-		ResponseEntity<Void> response = new RestTemplate(factory).exchange(request, Void.class);
+		RestClient restClient = RestClient.builder().requestFactory(factory)
+				.baseUrl("http://localhost:" + this.port).build();
+		ResponseEntity<Void> response = restClient.get().uri("/redirect").accept(MediaType.ALL)
+				.retrieve().toEntity(Void.class);
 
 		assertThat(response.getStatusCode()).isEqualTo(HttpStatus.SEE_OTHER);
 		assertThat(response.getHeaders().getLocation().toString()).isEqualTo("/");

spring-webflux/src/test/java/org/springframework/web/reactive/result/method/annotation/SseIntegrationTests.java

@@ -76,7 +76,6 @@ class SseIntegrationTests extends AbstractHttpHandlerIntegrationTests {
 
 	private void startServer(HttpServer httpServer, ClientHttpConnector connector) throws Exception {
 		super.startServer(httpServer);
-
 		this.webClient = WebClient
 				.builder()
 				.clientConnector(connector)

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

@@ -44,7 +44,6 @@ import org.springframework.http.HttpEntity;
 import org.springframework.http.HttpHeaders;
 import org.springframework.http.HttpStatus;
 import org.springframework.http.MediaType;
-import org.springframework.http.RequestEntity;
 import org.springframework.http.ResponseEntity;
 import org.springframework.http.client.HttpComponentsClientHttpRequestFactory;
 import org.springframework.http.converter.ByteArrayHttpMessageConverter;
@@ -59,7 +58,7 @@ import org.springframework.util.MimeTypeUtils;
 import org.springframework.util.MultiValueMap;
 import org.springframework.web.bind.annotation.RequestMapping;
 import org.springframework.web.bind.annotation.RequestPart;
-import org.springframework.web.client.RestTemplate;
+import org.springframework.web.client.RestClient;
 import org.springframework.web.context.support.AnnotationConfigWebApplicationContext;
 import org.springframework.web.multipart.MultipartFile;
 import org.springframework.web.multipart.MultipartResolver;
@@ -80,14 +79,13 @@ import static org.springframework.web.bind.annotation.RequestMethod.POST;
  */
 class RequestPartIntegrationTests {
 
-	private RestTemplate restTemplate;
-
 	private static Server server;
 
 	private static String baseUrl;
 
 	private static Path tempDirectory;
 
+	private RestClient restClient;
 
 	@BeforeAll
 	static void startServer() throws Exception {
@@ -137,8 +135,10 @@ class RequestPartIntegrationTests {
 
 		MultipartHttpMessageConverter converter = new MultipartHttpMessageConverter(converters);
 
-		restTemplate = new RestTemplate(new HttpComponentsClientHttpRequestFactory());
-		restTemplate.setMessageConverters(Collections.singletonList(converter));
+		this.restClient = RestClient.builder().baseUrl(baseUrl)
+				.requestFactory(new HttpComponentsClientHttpRequestFactory())
+				.configureMessageConverters(clientBuilder -> clientBuilder.addCustomConverter(converter))
+				.build();
 	}
 
 
@@ -162,16 +162,19 @@ class RequestPartIntegrationTests {
 				"content\r\n" +
 				"--" + boundaryText + "--\r\n ";
 
-		RequestEntity<byte[]> requestEntity =
-				RequestEntity.post(URI.create(baseUrl + "/standard-resolver/spr13319"))
-						.contentType(new MediaType(MediaType.MULTIPART_FORM_DATA, params))
-						.body(content.getBytes(StandardCharsets.US_ASCII));
+		ByteArrayHttpMessageConverter byteArrayConverter = new ByteArrayHttpMessageConverter();
+		byteArrayConverter.setSupportedMediaTypes(Collections.singletonList(MediaType.MULTIPART_FORM_DATA));
+		this.restClient = RestClient.builder().baseUrl(baseUrl)
+				.requestFactory(new HttpComponentsClientHttpRequestFactory())
+				.configureMessageConverters(clientBuilder -> clientBuilder.addCustomConverter(byteArrayConverter))
+				.build();
 
-		ByteArrayHttpMessageConverter converter = new ByteArrayHttpMessageConverter();
-		converter.setSupportedMediaTypes(Collections.singletonList(MediaType.MULTIPART_FORM_DATA));
-		this.restTemplate.setMessageConverters(Collections.singletonList(converter));
+		ResponseEntity<Void> responseEntity = this.restClient.post().uri("/standard-resolver/spr13319")
+				.contentType(new MediaType(MediaType.MULTIPART_FORM_DATA, params))
+				.body(content.getBytes(StandardCharsets.US_ASCII))
+				.retrieve()
+				.toBodilessEntity();
 
-		ResponseEntity<Void> responseEntity = restTemplate.exchange(requestEntity, Void.class);
 		assertThat(responseEntity.getStatusCode()).isEqualTo(HttpStatus.OK);
 	}
 
@@ -185,8 +188,9 @@ class RequestPartIntegrationTests {
 		headers.setContentType(new MediaType("application", "octet-stream", StandardCharsets.ISO_8859_1));
 		parts.add("iso-8859-1-data", new HttpEntity<>(new byte[] {(byte) 0xC4}, headers)); // SPR-13096
 
-		URI location = restTemplate.postForLocation(url, parts);
-		assertThat(location.toString()).isEqualTo(("http://localhost:8080/test/" + basename + "/logo.jpg"));
+		ResponseEntity<Void> response = this.restClient.post().uri(url).contentType(MediaType.MULTIPART_FORM_DATA)
+				.body(parts).retrieve().toBodilessEntity();
+		assertThat(response.getHeaders().getLocation().toString()).isEqualTo(("http://localhost:8080/test/" + basename + "/logo.jpg"));
 	}