JsonJacksonDeserializer.java

/*
 * GovWay - A customizable API Gateway 
 * https://govway.org
 * 
 * Copyright (c) 2005-2025 Link.it srl (https://link.it). 
 * 
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 3, as published by
 * the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 *
 */


package org.openspcoop2.utils.serialization;

import java.io.InputStream;
import java.io.Reader;
import java.util.ArrayList;
import java.util.List;

import com.fasterxml.jackson.databind.BeanDescription;
import com.fasterxml.jackson.databind.DeserializationConfig;
import com.fasterxml.jackson.databind.DeserializationFeature;
import com.fasterxml.jackson.databind.ObjectMapper;
import com.fasterxml.jackson.databind.deser.BeanDeserializerBuilder;
import com.fasterxml.jackson.databind.deser.BeanDeserializerFactory;
import com.fasterxml.jackson.databind.deser.BeanDeserializerModifier;
import com.fasterxml.jackson.databind.deser.DefaultDeserializationContext;
import com.fasterxml.jackson.databind.deser.DeserializerFactory;
import com.fasterxml.jackson.databind.introspect.BeanPropertyDefinition;

/** 
 * Contiene utility per effettuare la de-serializzazione di un oggetto
 *
 * @author Poli Andrea (apoli@link.it)
 * @author $Author$
 * @version $Rev$, $Date$
 */

public class JsonJacksonDeserializer implements IDeserializer{

    
    private static class BeanDeserializerModifierForIgnorables extends BeanDeserializerModifier {

        private static final long serialVersionUID = 1L;
        private List<String> ignorables;

        public BeanDeserializerModifierForIgnorables(List<String> properties) {
            if(properties!=null)
                this.ignorables = properties;
            else
                this.ignorables = new ArrayList<>();
        }

        @Override
        public BeanDeserializerBuilder updateBuilder(
                DeserializationConfig config, BeanDescription beanDesc,
                BeanDeserializerBuilder builder) {

            for(String ignorable : this.ignorables) {
                builder.addIgnorable(ignorable);                
            }

            return builder;
        }

        @Override
        public List<BeanPropertyDefinition> updateProperties(
                DeserializationConfig config, BeanDescription beanDesc,
                List<BeanPropertyDefinition> propDefs) {

            List<BeanPropertyDefinition> newPropDefs = new ArrayList<>();
            for(BeanPropertyDefinition propDef : propDefs) {
                if(!this.ignorables.contains(propDef.getName())) {
                    newPropDefs.add(propDef);
                }
            }
            return newPropDefs;
        }
    }


    private ObjectMapper mapper;

    public JsonJacksonDeserializer() {
        this(new SerializationConfig());
    }
    public JsonJacksonDeserializer(SerializationConfig config) {
        BeanDeserializerModifier modifier = new BeanDeserializerModifierForIgnorables(config.getExcludes());
        DeserializerFactory dFactory = BeanDeserializerFactory.instance.withDeserializerModifier(modifier);

        this.mapper = new ObjectMapper(null, null, new DefaultDeserializationContext.Impl(dFactory));
        this.mapper.setDateFormat(config.getDf());
        if(config.isSerializeEnumAsString())
            this.mapper.enable(DeserializationFeature.READ_ENUMS_USING_TO_STRING);

    }

    @Override
    public Object getObject(String s, Class<?> classType) throws IOException{
        try {
            return this.mapper.readValue(s, classType);
        } catch (java.io.IOException e) {
            throw new IOException(e);
        }
    }

    @Override
    public Object readObject(InputStream is, Class<?> classType) throws IOException {
        try {
            return this.mapper.readValue(is, classType);
        } catch (java.io.IOException e) {
            throw new IOException(e);
        }
    }

    @Override
    public Object readObject(Reader reader, Class<?> classType) throws IOException {
        try {
            return this.mapper.readValue(reader, classType);
        } catch (java.io.IOException e) {
            throw new IOException(e);
        }
    }
}