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/* * Copyright 2002-2018 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.servlet.mvc.method.annotation; import org.springframework.core.MethodParameter; import org.springframework.http.MediaType; import org.springframework.http.converter.HttpMessageConverter; import org.springframework.http.server.ServerHttpRequest; import org.springframework.http.server.ServerHttpResponse; import org.springframework.lang.Nullable; /** * Allows customizing the response after the execution of an {@code @ResponseBody} * or a {@code ResponseEntity} controller method but before the body is written * with an {@code HttpMessageConverter}. * * <p>Implementations may be registered directly with * {@code RequestMappingHandlerAdapter} and {@code ExceptionHandlerExceptionResolver} * or more likely annotated with {@code @ControllerAdvice} in which case they * will be auto-detected by both. * * @author Rossen Stoyanchev * @since 4.1 * @param <T> the body type */ public interface ResponseBodyAdvice<T> { /** * Whether this component supports the given controller method return type * and the selected {@code HttpMessageConverter} type. * @param returnType the return type * @param converterType the selected converter type * @return {@code true} if {@link #beforeBodyWrite} should be invoked; * {@code false} otherwise */ boolean supports(MethodParameter returnType, Class<? extends HttpMessageConverter<?>> converterType); /** * Invoked after an {@code HttpMessageConverter} is selected and just before * its write method is invoked. * @param body the body to be written * @param returnType the return type of the controller method * @param selectedContentType the content type selected through content negotiation * @param selectedConverterType the converter type selected to write to the response * @param request the current request * @param response the current response * @return the body that was passed in or a modified (possibly new) instance */ @Nullable T beforeBodyWrite(@Nullable T body, MethodParameter returnType, MediaType selectedContentType, Class<? extends HttpMessageConverter<?>> selectedConverterType, ServerHttpRequest request, ServerHttpResponse response); }