JacksonCodec.java

/*
 * The MIT License
 *
 * Copyright 2015 Tim Boudreau.
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 */
package com.mastfrog.acteur.mongo.async;

import com.fasterxml.jackson.core.JsonProcessingException;
import com.fasterxml.jackson.databind.ObjectMapper;
import com.google.inject.Inject;
import static com.mastfrog.util.Exceptions.chuck;
import io.netty.buffer.ByteBuf;
import io.netty.buffer.ByteBufInputStream;
import io.netty.buffer.Unpooled;
import java.io.IOException;
import javax.inject.Provider;
import org.bson.BsonReader;
import org.bson.BsonWriter;
import org.bson.codecs.Codec;
import org.bson.codecs.DecoderContext;
import org.bson.codecs.EncoderContext;

/**
 * Uses Jackson to enable MongoDB to support types without writing custom
 * codecs for them.
 *
 * @author Tim Boudreau
 * @param <T>The type
 */
final class JacksonCodec<T> implements Codec<T> {

    private final Provider<ObjectMapper> mapper;
    private final Provider<ByteBufCodec> json;
    private final Class<T> type;

    @Inject
    JacksonCodec(Provider<ObjectMapper> mapper, Provider<ByteBufCodec> json, Class<T> type) {
        this.mapper = mapper;
        this.json = json;
        this.type = type;
    }

    @Override
    public void encode(BsonWriter writer, T t, EncoderContext ec) {
        try {
            byte[] bytes = mapper.get().writeValueAsBytes(t);
            json.get().encode(writer, Unpooled.wrappedBuffer(bytes), ec);
        } catch (JsonProcessingException ex) {
            chuck(ex);
        }
    }

    @Override
    public Class<T> getEncoderClass() {
        return type;
    }

    @Override
    public T decode(BsonReader reader, DecoderContext dc) {
        ByteBuf buf = json.get().decode(reader, dc);
        try {
            return mapper.get().readValue(new ByteBufInputStream(buf), type);
        } catch (IOException ex) {
            return chuck(ex);
        }
    }
}