001/*
002 * Copyright 2002-2018 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.http.converter.json;
018
019import java.io.IOException;
020
021import com.fasterxml.jackson.core.JsonGenerator;
022import com.fasterxml.jackson.databind.ObjectMapper;
023
024import org.springframework.http.MediaType;
025
026/**
027 * Implementation of {@link org.springframework.http.converter.HttpMessageConverter} that can read and
028 * write JSON using <a href="https://wiki.fasterxml.com/JacksonHome">Jackson 2.x's</a> {@link ObjectMapper}.
029 *
030 * <p>This converter can be used to bind to typed beans, or untyped {@code HashMap} instances.
031 *
032 * <p>By default, this converter supports {@code application/json} and {@code application/*+json}
033 * with {@code UTF-8} character set. This can be overridden by setting the
034 * {@link #setSupportedMediaTypes supportedMediaTypes} property.
035 *
036 * <p>The default constructor uses the default configuration provided by {@link Jackson2ObjectMapperBuilder}.
037 *
038 * <p>Compatible with Jackson 2.6 and higher, as of Spring 4.3.
039 *
040 * @author Arjen Poutsma
041 * @author Keith Donald
042 * @author Rossen Stoyanchev
043 * @author Juergen Hoeller
044 * @author Sebastien Deleuze
045 * @since 3.1.2
046 */
047public class MappingJackson2HttpMessageConverter extends AbstractJackson2HttpMessageConverter {
048
049        private String jsonPrefix;
050
051
052        /**
053         * Construct a new {@link MappingJackson2HttpMessageConverter} using default configuration
054         * provided by {@link Jackson2ObjectMapperBuilder}.
055         */
056        public MappingJackson2HttpMessageConverter() {
057                this(Jackson2ObjectMapperBuilder.json().build());
058        }
059
060        /**
061         * Construct a new {@link MappingJackson2HttpMessageConverter} with a custom {@link ObjectMapper}.
062         * You can use {@link Jackson2ObjectMapperBuilder} to build it easily.
063         * @see Jackson2ObjectMapperBuilder#json()
064         */
065        public MappingJackson2HttpMessageConverter(ObjectMapper objectMapper) {
066                super(objectMapper, MediaType.APPLICATION_JSON, new MediaType("application", "*+json"));
067        }
068
069        /**
070         * Specify a custom prefix to use for this view's JSON output.
071         * Default is none.
072         * @see #setPrefixJson
073         */
074        public void setJsonPrefix(String jsonPrefix) {
075                this.jsonPrefix = jsonPrefix;
076        }
077
078        /**
079         * Indicate whether the JSON output by this view should be prefixed with ")]}', ". Default is false.
080         * <p>Prefixing the JSON string in this manner is used to help prevent JSON Hijacking.
081         * The prefix renders the string syntactically invalid as a script so that it cannot be hijacked.
082         * This prefix should be stripped before parsing the string as JSON.
083         * @see #setJsonPrefix
084         */
085        public void setPrefixJson(boolean prefixJson) {
086                this.jsonPrefix = (prefixJson ? ")]}', " : null);
087        }
088
089
090        @Override
091        @SuppressWarnings("deprecation")
092        protected void writePrefix(JsonGenerator generator, Object object) throws IOException {
093                if (this.jsonPrefix != null) {
094                        generator.writeRaw(this.jsonPrefix);
095                }
096                String jsonpFunction =
097                                (object instanceof MappingJacksonValue ? ((MappingJacksonValue) object).getJsonpFunction() : null);
098                if (jsonpFunction != null) {
099                        generator.writeRaw("/**/");
100                        generator.writeRaw(jsonpFunction + "(");
101                }
102        }
103
104        @Override
105        @SuppressWarnings("deprecation")
106        protected void writeSuffix(JsonGenerator generator, Object object) throws IOException {
107                String jsonpFunction =
108                                (object instanceof MappingJacksonValue ? ((MappingJacksonValue) object).getJsonpFunction() : null);
109                if (jsonpFunction != null) {
110                        generator.writeRaw(");");
111                }
112        }
113
114}