001/* 002 * Copyright 2002-2017 the original author or authors. 003 * 004 * Licensed under the Apache License, Version 2.0 (the "License"); 005 * you may not use this file except in compliance with the License. 006 * You may obtain a copy of the License at 007 * 008 * https://www.apache.org/licenses/LICENSE-2.0 009 * 010 * Unless required by applicable law or agreed to in writing, software 011 * distributed under the License is distributed on an "AS IS" BASIS, 012 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 013 * See the License for the specific language governing permissions and 014 * limitations under the License. 015 */ 016 017package org.springframework.web.servlet.mvc.method.annotation; 018 019import com.fasterxml.jackson.annotation.JsonView; 020 021import org.springframework.core.MethodParameter; 022import org.springframework.http.MediaType; 023import org.springframework.http.converter.HttpMessageConverter; 024import org.springframework.http.converter.json.MappingJacksonValue; 025import org.springframework.http.server.ServerHttpRequest; 026import org.springframework.http.server.ServerHttpResponse; 027import org.springframework.util.Assert; 028 029/** 030 * A {@link ResponseBodyAdvice} implementation that adds support for Jackson's 031 * {@code @JsonView} annotation declared on a Spring MVC {@code @RequestMapping} 032 * or {@code @ExceptionHandler} method. 033 * 034 * <p>The serialization view specified in the annotation will be passed in to the 035 * {@link org.springframework.http.converter.json.MappingJackson2HttpMessageConverter} 036 * which will then use it to serialize the response body. 037 * 038 * <p>Note that despite {@code @JsonView} allowing for more than one class to 039 * be specified, the use for a response body advice is only supported with 040 * exactly one class argument. Consider the use of a composite interface. 041 * 042 * @author Rossen Stoyanchev 043 * @since 4.1 044 * @see com.fasterxml.jackson.annotation.JsonView 045 * @see com.fasterxml.jackson.databind.ObjectMapper#writerWithView(Class) 046 */ 047public class JsonViewResponseBodyAdvice extends AbstractMappingJacksonResponseBodyAdvice { 048 049 @Override 050 public boolean supports(MethodParameter returnType, Class<? extends HttpMessageConverter<?>> converterType) { 051 return super.supports(returnType, converterType) && returnType.hasMethodAnnotation(JsonView.class); 052 } 053 054 @Override 055 protected void beforeBodyWriteInternal(MappingJacksonValue bodyContainer, MediaType contentType, 056 MethodParameter returnType, ServerHttpRequest request, ServerHttpResponse response) { 057 058 JsonView ann = returnType.getMethodAnnotation(JsonView.class); 059 Assert.state(ann != null, "No JsonView annotation"); 060 061 Class<?>[] classes = ann.value(); 062 if (classes.length != 1) { 063 throw new IllegalArgumentException( 064 "@JsonView only supported for response body advice with exactly 1 class argument: " + returnType); 065 } 066 067 bodyContainer.setSerializationView(classes[0]); 068 } 069 070}