Java tutorial
/* * Copyright 2002-2019 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.IOException; import java.nio.charset.Charset; import org.springframework.http.HttpHeaders; import org.springframework.http.HttpStatus; import org.springframework.http.MediaType; import org.springframework.http.client.ClientHttpResponse; import org.springframework.lang.Nullable; import org.springframework.util.FileCopyUtils; /** * Spring's default implementation of the {@link ResponseErrorHandler} interface. * * <p>This error handler checks for the status code on the {@link ClientHttpResponse}: * Any code with series {@link org.springframework.http.HttpStatus.Series#CLIENT_ERROR} * or {@link org.springframework.http.HttpStatus.Series#SERVER_ERROR} is considered to be * an error; this behavior can be changed by overriding the {@link #hasError(HttpStatus)} * method. Unknown status codes will be ignored by {@link #hasError(ClientHttpResponse)}. * * @author Arjen Poutsma * @author Rossen Stoyanchev * @author Juergen Hoeller * @since 3.0 * @see RestTemplate#setErrorHandler */ public class DefaultResponseErrorHandler implements ResponseErrorHandler { /** * Delegates to {@link #hasError(HttpStatus)} (for a standard status enum value) or * {@link #hasError(int)} (for an unknown status code) with the response status code. * @see ClientHttpResponse#getRawStatusCode() * @see #hasError(HttpStatus) * @see #hasError(int) */ @Override public boolean hasError(ClientHttpResponse response) throws IOException { int rawStatusCode = response.getRawStatusCode(); HttpStatus statusCode = HttpStatus.resolve(rawStatusCode); return (statusCode != null ? hasError(statusCode) : hasError(rawStatusCode)); } /** * Template method called from {@link #hasError(ClientHttpResponse)}. * <p>The default implementation checks {@link HttpStatus#isError()}. * Can be overridden in subclasses. * @param statusCode the HTTP status code as enum value * @return {@code true} if the response indicates an error; {@code false} otherwise * @see HttpStatus#isError() */ protected boolean hasError(HttpStatus statusCode) { return statusCode.isError(); } /** * Template method called from {@link #hasError(ClientHttpResponse)}. * <p>The default implementation checks if the given status code is * {@link org.springframework.http.HttpStatus.Series#CLIENT_ERROR CLIENT_ERROR} or * {@link org.springframework.http.HttpStatus.Series#SERVER_ERROR SERVER_ERROR}. * Can be overridden in subclasses. * @param unknownStatusCode the HTTP status code as raw value * @return {@code true} if the response indicates an error; {@code false} otherwise * @since 4.3.21 * @see org.springframework.http.HttpStatus.Series#CLIENT_ERROR * @see org.springframework.http.HttpStatus.Series#SERVER_ERROR */ protected boolean hasError(int unknownStatusCode) { HttpStatus.Series series = HttpStatus.Series.resolve(unknownStatusCode); return (series == HttpStatus.Series.CLIENT_ERROR || series == HttpStatus.Series.SERVER_ERROR); } /** * Delegates to {@link #handleError(ClientHttpResponse, HttpStatus)} with the * response status code. * @throws UnknownHttpStatusCodeException in case of an unresolvable status code * @see #handleError(ClientHttpResponse, HttpStatus) */ @Override public void handleError(ClientHttpResponse response) throws IOException { HttpStatus statusCode = HttpStatus.resolve(response.getRawStatusCode()); if (statusCode == null) { throw new UnknownHttpStatusCodeException(response.getRawStatusCode(), response.getStatusText(), response.getHeaders(), getResponseBody(response), getCharset(response)); } handleError(response, statusCode); } /** * Handle the error in the given response with the given resolved status code. * <p>The default implementation throws an {@link HttpClientErrorException} * if the status code is {@link org.springframework.http.HttpStatus.Series#CLIENT_ERROR * CLIENT_ERROR}, an {@link HttpServerErrorException} if it is * {@link org.springframework.http.HttpStatus.Series#SERVER_ERROR SERVER_ERROR}, * or an {@link UnknownHttpStatusCodeException} in other cases. * @since 5.0 * @see HttpClientErrorException#create * @see HttpServerErrorException#create */ protected void handleError(ClientHttpResponse response, HttpStatus statusCode) throws IOException { String statusText = response.getStatusText(); HttpHeaders headers = response.getHeaders(); byte[] body = getResponseBody(response); Charset charset = getCharset(response); switch (statusCode.series()) { case CLIENT_ERROR: throw HttpClientErrorException.create(statusCode, statusText, headers, body, charset); case SERVER_ERROR: throw HttpServerErrorException.create(statusCode, statusText, headers, body, charset); default: throw new UnknownHttpStatusCodeException(statusCode.value(), statusText, headers, body, charset); } } /** * Determine the HTTP status of the given response. * @param response the response to inspect * @return the associated HTTP status * @throws IOException in case of I/O errors * @throws UnknownHttpStatusCodeException in case of an unknown status code * that cannot be represented with the {@link HttpStatus} enum * @since 4.3.8 * @deprecated as of 5.0, in favor of {@link #handleError(ClientHttpResponse, HttpStatus)} */ @Deprecated protected HttpStatus getHttpStatusCode(ClientHttpResponse response) throws IOException { HttpStatus statusCode = HttpStatus.resolve(response.getRawStatusCode()); if (statusCode == null) { throw new UnknownHttpStatusCodeException(response.getRawStatusCode(), response.getStatusText(), response.getHeaders(), getResponseBody(response), getCharset(response)); } return statusCode; } /** * Read the body of the given response (for inclusion in a status exception). * @param response the response to inspect * @return the response body as a byte array, * or an empty byte array if the body could not be read * @since 4.3.8 */ protected byte[] getResponseBody(ClientHttpResponse response) { try { return FileCopyUtils.copyToByteArray(response.getBody()); } catch (IOException ex) { // ignore } return new byte[0]; } /** * Determine the charset of the response (for inclusion in a status exception). * @param response the response to inspect * @return the associated charset, or {@code null} if none * @since 4.3.8 */ @Nullable protected Charset getCharset(ClientHttpResponse response) { HttpHeaders headers = response.getHeaders(); MediaType contentType = headers.getContentType(); return (contentType != null ? contentType.getCharset() : null); } }