GdxArrayCodec.java

package app.virtualhex.gdx.engine.data;

import com.badlogic.gdx.utils.Array;
import org.bson.BsonReader;
import org.bson.BsonType;
import org.bson.BsonValue;
import org.bson.BsonWriter;
import org.bson.codecs.BsonValueCodecProvider;
import org.bson.codecs.Codec;
import org.bson.codecs.DecoderContext;
import org.bson.codecs.EncoderContext;
import org.bson.codecs.configuration.CodecProvider;
import org.bson.codecs.configuration.CodecRegistry;

import static org.bson.assertions.Assertions.notNull;

class GdxArrayCodec implements Codec<Array<?>> {
    private final CodecRegistry codecRegistry;

    public GdxArrayCodec(CodecRegistry codecRegistry) {
        this.codecRegistry = notNull("codecRegistry", codecRegistry);
    }

    @Override
    public Array<BsonValue> decode(BsonReader reader, DecoderContext decoderContext) {
        reader.readStartArray();

        Array<BsonValue> array = new Array<>();

        while (reader.readBsonType() != BsonType.END_OF_DOCUMENT) {
            array.add(readValue(reader, decoderContext));
        }

        reader.readEndArray();

        return array;
    }

    @Override
    public void encode(BsonWriter writer, Array<?> array, EncoderContext encoderContext) {
        writer.writeStartArray();

        for (Object value: array) {
            Codec codec = codecRegistry.get(value.getClass());
            encoderContext.encodeWithChildContext(codec, writer, value);
        }

        writer.writeEndArray();
    }

    @Override
    public Class<Array<?>> getEncoderClass() {
        return (Class<Array<?>>)(Class<?>)Array.class;
    }

    protected BsonValue readValue(final BsonReader reader, final DecoderContext decoderContext) {
        return codecRegistry.get(
                BsonValueCodecProvider.getClassForBsonType(reader.getCurrentBsonType())
        ).decode(reader, decoderContext);
    }
}

GdxArrayCodecProvider.java

package app.virtualhex.gdx.engine.data;

import com.badlogic.gdx.utils.Array;
import org.bson.codecs.Codec;
import org.bson.codecs.configuration.CodecProvider;
import org.bson.codecs.configuration.CodecRegistry;

public class GdxArrayCodecProvider implements CodecProvider {
    @Override
    public <T> Codec<T> get(final Class<T> clazz, final CodecRegistry registry) {
        if (clazz == Array.class) {
            return (Codec<T>) new GdxArrayCodec(registry);
        }

        // CodecProvider returns null if it's not a provider for the requresed Class
        return null;
    }
}