IdAnnotations.java

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/* *********************************************************************** *
 * project: org.matsim.*
 * IdAnnotations.java
 *                                                                         *
 * *********************************************************************** *
 *                                                                         *
 * copyright       : (C) 2023 by the members listed in the COPYING,        *
 *                   LICENSE and WARRANTY file.                            *
 * email           : info at matsim dot org                                *
 *                                                                         *
 * *********************************************************************** *
 *                                                                         *
 *   This program is free software; you can redistribute it and/or modify  *
 *   it under the terms of the GNU General Public License as published by  *
 *   the Free Software Foundation; either version 2 of the License, or     *
 *   (at your option) any later version.                                   *
 *   See also COPYING, LICENSE and WARRANTY file                           *
 *                                                                         *
 * *********************************************************************** */

package org.matsim.api.core.v01;

import java.io.IOException;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.util.HashMap;
import java.util.Map;

import com.fasterxml.jackson.annotation.JacksonAnnotationsInside;
import com.fasterxml.jackson.core.JacksonException;
import com.fasterxml.jackson.core.JsonGenerator;
import com.fasterxml.jackson.core.JsonParser;
import com.fasterxml.jackson.databind.BeanProperty;
import com.fasterxml.jackson.databind.DeserializationContext;
import com.fasterxml.jackson.databind.JavaType;
import com.fasterxml.jackson.databind.JsonDeserializer;
import com.fasterxml.jackson.databind.JsonMappingException;
import com.fasterxml.jackson.databind.JsonNode;
import com.fasterxml.jackson.databind.SerializerProvider;
import com.fasterxml.jackson.databind.annotation.JsonDeserialize;
import com.fasterxml.jackson.databind.annotation.JsonSerialize;
import com.fasterxml.jackson.databind.deser.ContextualDeserializer;
import com.fasterxml.jackson.databind.deser.std.StdDeserializer;
import com.fasterxml.jackson.databind.ser.std.StdSerializer;

public interface IdAnnotations {

    @Retention(RetentionPolicy.RUNTIME)
    @JacksonAnnotationsInside
    @JsonSerialize(using = JsonIdSerializer.class)
    @JsonDeserialize(using = JsonIdContextualDeserializer.class)
    public @interface JsonId {

    }

    class JsonIdSerializer<T> extends StdSerializer<T> {

        protected JsonIdSerializer() {
            this(null);
        }

        protected JsonIdSerializer(Class<T> vc) {
            super(vc);
        }

        @Override
        public void serialize(T value, JsonGenerator gen, SerializerProvider provider) throws IOException {
            gen.writeString(value.toString());
        }

    }

    class JsonIdContextualDeserializer<T> extends StdDeserializer<Id<T>> implements ContextualDeserializer {

        private Class<T> idClass;

        protected JsonIdContextualDeserializer() {
            this(null);
        }

        protected JsonIdContextualDeserializer(Class<T> idClass) {
            super(Object.class);
            this.idClass = idClass;
        }

        @Override
        public JsonDeserializer<?> createContextual(DeserializationContext ctxt, BeanProperty property)
                throws JsonMappingException {

            final Class<? extends Object> idClass;
            {
                final JavaType type;
                if (property != null)
                    type = property.getType();
                else {
                    type = ctxt.getContextualType();
                }
                idClass = type.containedType(0).getRawClass();
            }

            return JsonIdDeserializer.getInstance(idClass);
        }

        @Override
        public Id<T> deserialize(JsonParser jp, DeserializationContext ctxt) throws IOException, JacksonException {
            JsonNode node = jp.getCodec().readTree(jp);
            return Id.create(node.asText(), idClass);
        }

    }

    class JsonIdDeserializer<T> extends StdDeserializer<Id<T>> {

        private static final Map<Class<?>, JsonIdDeserializer<?>> CACHE = new HashMap<>();

        public static JsonIdDeserializer<?> getInstance(Class<?> clazz) {
            return CACHE.computeIfAbsent(clazz, k -> new JsonIdDeserializer<>(k));
        }

        private final Class<T> idClass;

        private JsonIdDeserializer() {
            this(null);
        }

        private JsonIdDeserializer(Class<T> idClass) {
            super(Object.class);
            this.idClass = idClass;
        }

        @Override
        public Id<T> deserialize(JsonParser jp, DeserializationContext ctxt) throws IOException {
            JsonNode node = jp.getCodec().readTree(jp);
            return Id.create(node.asText(), idClass);
        }

    }

}