Avoid deprecated extractor in StatusHandler

spring-web/src/main/java/org/springframework/web/client/StatusHandler.java

@@ -19,21 +19,28 @@
 import java.io.ByteArrayInputStream;
 import java.io.IOException;
 import java.io.InputStream;
+import java.lang.reflect.Type;
 import java.nio.charset.Charset;
 import java.nio.charset.StandardCharsets;
 import java.util.List;
 import java.util.function.Function;
 import java.util.function.Predicate;
 
+import org.apache.commons.logging.Log;
+import org.apache.commons.logging.LogFactory;
 import org.jspecify.annotations.Nullable;
 
 import org.springframework.core.ResolvableType;
 import org.springframework.core.log.LogFormatUtils;
 import org.springframework.http.HttpHeaders;
 import org.springframework.http.HttpRequest;
 import org.springframework.http.HttpStatusCode;
+import org.springframework.http.MediaType;
 import org.springframework.http.client.ClientHttpResponse;
+import org.springframework.http.converter.GenericHttpMessageConverter;
 import org.springframework.http.converter.HttpMessageConverter;
+import org.springframework.http.converter.HttpMessageNotReadableException;
+import org.springframework.http.converter.SmartHttpMessageConverter;
 import org.springframework.util.Assert;
 import org.springframework.util.CollectionUtils;
 import org.springframework.util.ObjectUtils;
@@ -48,6 +55,8 @@
  */
 final class StatusHandler {
 
+	private static final Log logger = LogFactory.getLog(StatusHandler.class);
+
 	private final ResponsePredicate predicate;
 
 	private final RestClient.ResponseSpec.ErrorHandler handler;
@@ -163,16 +172,13 @@ private static String getErrorMessage(
 		return preface + bodyText;
 	}
 
-	@SuppressWarnings({"NullAway", "removal"})
+	@SuppressWarnings("NullAway")
 	private static Function<ResolvableType, ? extends @Nullable Object> initBodyConvertFunction(
 			ClientHttpResponse response, byte[] body, List<HttpMessageConverter<?>> messageConverters) {
 
 		return resolvableType -> {
 			try {
-				HttpMessageConverterExtractor<?> extractor =
-						new HttpMessageConverterExtractor<>(resolvableType.getType(), messageConverters);
-
-				return extractor.extractData(new ClientHttpResponseDecorator(response) {
+				return extractData(resolvableType, messageConverters, new ClientHttpResponseDecorator(response) {
 					@Override
 					public InputStream getBody() {
 						return new ByteArrayInputStream(body);
@@ -185,6 +191,65 @@ public InputStream getBody() {
 		};
 	}
 
+	@SuppressWarnings({"rawtypes", "unchecked"})
+	private static @Nullable Object extractData(ResolvableType resolvableType,
+			List<HttpMessageConverter<?>> messageConverters, ClientHttpResponse response) throws IOException {
+
+		IntrospectingClientHttpResponse responseWrapper = new IntrospectingClientHttpResponse(response);
+		if (!responseWrapper.hasMessageBody() || responseWrapper.hasEmptyMessageBody()) {
+			return null;
+		}
+		MediaType contentType = getContentType(responseWrapper);
+		Type responseType = resolvableType.getType();
+		Class<?> responseClass = (responseType instanceof Class<?> clazz ? clazz : null);
+
+		try {
+			for (HttpMessageConverter<?> messageConverter : messageConverters) {
+				if (messageConverter instanceof GenericHttpMessageConverter genericMessageConverter) {
+					if (genericMessageConverter.canRead(responseType, null, contentType)) {
+						if (logger.isDebugEnabled()) {
+							logger.debug("Reading to [" + resolvableType + "]");
+						}
+						return genericMessageConverter.read(responseType, null, responseWrapper);
+					}
+				}
+				else if (messageConverter instanceof SmartHttpMessageConverter smartMessageConverter) {
+					if (smartMessageConverter.canRead(resolvableType, contentType)) {
+						if (logger.isDebugEnabled()) {
+							logger.debug("Reading to [" + resolvableType + "]");
+						}
+						return smartMessageConverter.read(resolvableType, responseWrapper, null);
+					}
+				}
+				else if (responseClass != null && messageConverter.canRead(responseClass, contentType)) {
+					if (logger.isDebugEnabled()) {
+						logger.debug("Reading to [" + responseClass.getName() + "] as \"" + contentType + "\"");
+					}
+					return messageConverter.read((Class) responseClass, responseWrapper);
+				}
+			}
+		}
+		catch (IOException | HttpMessageNotReadableException ex) {
+			throw new RestClientException("Error while extracting response for type [" +
+					responseType + "] and content type [" + contentType + "]", ex);
+		}
+
+		throw new UnknownContentTypeException(responseType, contentType,
+				responseWrapper.getStatusCode(), responseWrapper.getStatusText(),
+				responseWrapper.getHeaders(), RestClientUtils.getBody(responseWrapper));
+	}
+
+	private static MediaType getContentType(ClientHttpResponse response) {
+		MediaType contentType = response.getHeaders().getContentType();
+		if (contentType == null) {
+			if (logger.isTraceEnabled()) {
+				logger.trace("No content-type, using 'application/octet-stream'");
+			}
+			contentType = MediaType.APPLICATION_OCTET_STREAM;
+		}
+		return contentType;
+	}
+
 
 	@FunctionalInterface
 	private interface ResponsePredicate {

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

@@ -0,0 +1,154 @@
+/*
+ * Copyright 2002-present the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.springframework.web.client;
+
+import java.io.ByteArrayInputStream;
+import java.io.IOException;
+import java.lang.reflect.Type;
+import java.nio.charset.StandardCharsets;
+import java.util.List;
+
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+
+import org.springframework.core.ParameterizedTypeReference;
+import org.springframework.core.ResolvableType;
+import org.springframework.http.HttpHeaders;
+import org.springframework.http.HttpInputMessage;
+import org.springframework.http.HttpStatus;
+import org.springframework.http.MediaType;
+import org.springframework.http.client.ClientHttpResponse;
+import org.springframework.http.converter.GenericHttpMessageConverter;
+import org.springframework.http.converter.HttpMessageConverter;
+import org.springframework.http.converter.SmartHttpMessageConverter;
+
+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.ArgumentMatchers.eq;
+import static org.mockito.ArgumentMatchers.isNull;
+import static org.mockito.BDDMockito.given;
+import static org.mockito.Mockito.mock;
+
+/**
+ * Tests for {@link StatusHandler}.
+ *
+ * @author Sakshi Chitnis
+ */
+class StatusHandlerTests {
+
+	private static final MediaType CONTENT_TYPE = MediaType.TEXT_PLAIN;
+
+	private static final String BODY = "Foo";
+
+	private final ClientHttpResponse response = mock();
+
+
+	@BeforeEach
+	void setUp() throws IOException {
+		HttpHeaders headers = new HttpHeaders();
+		headers.setContentType(CONTENT_TYPE);
+		headers.setContentLength(BODY.length());
+		given(this.response.getStatusCode()).willReturn(HttpStatus.BAD_REQUEST);
+		given(this.response.getStatusText()).willReturn(HttpStatus.BAD_REQUEST.getReasonPhrase());
+		given(this.response.getHeaders()).willReturn(headers);
+		given(this.response.getBody()).willReturn(new ByteArrayInputStream(BODY.getBytes(StandardCharsets.UTF_8)));
+	}
+
+
+	@Test
+	void convertBodyWithHttpMessageConverter() throws IOException {
+		HttpMessageConverter<String> converter = mock();
+		given(converter.canRead(String.class, CONTENT_TYPE)).willReturn(true);
+		given(converter.read(eq(String.class), any(HttpInputMessage.class))).willReturn(BODY);
+
+		RestClientResponseException exception = createException(converter);
+
+		assertThat(exception.getResponseBodyAs(String.class)).isEqualTo(BODY);
+	}
+
+	@Test
+	void convertBodyWithGenericHttpMessageConverter() throws IOException {
+		ParameterizedTypeReference<List<String>> targetType = new ParameterizedTypeReference<>() {};
+		Type type = targetType.getType();
+		GenericHttpMessageConverter<List<String>> converter = mock();
+		given(converter.canRead(type, null, CONTENT_TYPE)).willReturn(true);
+		given(converter.read(eq(type), isNull(), any(HttpInputMessage.class))).willReturn(List.of(BODY));
+
+		RestClientResponseException exception = createException(converter);
+
+		assertThat(exception.getResponseBodyAs(targetType)).containsExactly(BODY);
+	}
+
+	@Test
+	void convertBodyWithSmartHttpMessageConverter() throws IOException {
+		ParameterizedTypeReference<List<String>> targetType = new ParameterizedTypeReference<>() {};
+		ResolvableType resolvableType = ResolvableType.forType(targetType.getType());
+		SmartHttpMessageConverter<List<String>> converter = mock();
+		given(converter.canRead(resolvableType, CONTENT_TYPE)).willReturn(true);
+		given(converter.read(eq(resolvableType), any(HttpInputMessage.class), isNull())).willReturn(List.of(BODY));
+
+		RestClientResponseException exception = createException(converter);
+
+		assertThat(exception.getResponseBodyAs(targetType)).containsExactly(BODY);
+	}
+
+	@Test
+	void emptyBodyIsNotConverted() throws IOException {
+		HttpHeaders headers = new HttpHeaders();
+		headers.setContentLength(0);
+		given(this.response.getHeaders()).willReturn(headers);
+		given(this.response.getBody()).willReturn(new ByteArrayInputStream(new byte[0]));
+		HttpMessageConverter<String> converter = mock();
+
+		RestClientResponseException exception = createException(converter);
+
+		assertThat(exception.getResponseBodyAs(String.class)).isNull();
+	}
+
+	@Test
+	void cannotConvertBody() throws IOException {
+		HttpMessageConverter<String> converter = mock();
+		given(converter.canRead(String.class, CONTENT_TYPE)).willReturn(false);
+
+		RestClientResponseException exception = createException(converter);
+
+		assertThatExceptionOfType(UnknownContentTypeException.class)
+				.isThrownBy(() -> exception.getResponseBodyAs(String.class))
+				.satisfies(ex -> assertThat(ex.getResponseBodyAsString()).isEqualTo(BODY));
+	}
+
+	@Test
+	void converterThrowsIOException() throws IOException {
+		HttpMessageConverter<String> converter = mock();
+		given(converter.canRead(String.class, CONTENT_TYPE)).willReturn(true);
+		given(converter.read(eq(String.class), any(HttpInputMessage.class))).willThrow(IOException.class);
+
+		RestClientResponseException exception = createException(converter);
+
+		assertThatExceptionOfType(RestClientException.class)
+				.isThrownBy(() -> exception.getResponseBodyAs(String.class))
+				.withMessageContaining("Error while extracting response for type [class java.lang.String] " +
+						"and content type [text/plain]")
+				.withCauseInstanceOf(IOException.class);
+	}
+
+	private RestClientResponseException createException(HttpMessageConverter<?> converter) throws IOException {
+		return StatusHandler.createException(this.response, List.of(converter));
+	}
+
+}