Jpa Json Converter

JpaJsonConverter.java

package sample.json;

import com.fasterxml.jackson.core.JsonProcessingException;
import com.fasterxml.jackson.databind.ObjectMapper;
import com.fasterxml.jackson.databind.ObjectReader;
import com.google.common.reflect.TypeToken;
import sample.json.Json;
import org.springframework.util.StringUtils;

import javax.annotation.Nonnull;
import javax.persistence.AttributeConverter;
import java.io.IOException;

public abstract class JpaJsonConverter<TAttribute> implements AttributeConverter<TAttribute, String> {
    private final TypeToken<TAttribute> type = new TypeToken<TAttribute>(getClass()) {
    };
    private ObjectReader reader;

    @Override
    public String convertToDatabaseColumn(TAttribute attribute) {
        if (attribute == null) {
            return null;
        }
        try {
            return serialize(attribute);
        } catch (JsonProcessingException e) {
            throw new RuntimeException("cannot serialize attribute " + attribute, e);
        }
    }

    protected String serialize(@Nonnull TAttribute attribute) throws JsonProcessingException {
        return mapper().writeValueAsString(attribute);
    }

    @Nonnull
    public ObjectMapper mapper() {
        return Json.getMapper();
    }

    @Override
    public TAttribute convertToEntityAttribute(String dbData) {
        if (dbData == null || StringUtils.isEmpty(dbData)) {
            return valueForEmptyColumn();
        }
        try {
            return deserialize(dbData);
        } catch (IOException e) {
            throw new RuntimeException("cannot deserialize attribute: " + type + " from: " + dbData, e);
        }
    }

    public TAttribute valueForEmptyColumn() {
        return null;
    }

    protected TAttribute deserialize(@Nonnull String dbData) throws IOException {
        ObjectReader reader = getReader();
        return reader.readValue(dbData);
    }

    private ObjectReader getReader() {
        //constructing reader takes roughly ~20% deserialization time
        ObjectMapper mapper = mapper();
        if (reader == null) {
            reader = mapper.readerFor(mapper.constructType(type.getType()));
        }
        return reader;
    }
}

UsageSampe.java

package sample.json;

class EntityChild {
  String name;
}

class Entity {
  @Convert(converter = EntityChildrenListConverter.class)
  List<EntityChild> children = new ArrayList<>();
  
  public static class EntityChildrenListConverter extends JpaJsonConverter<List<EntityChild>> {
  }
}

Hi, I got to your code because I am having an issue with Jsons we are storing in the columns. Basically I have a question, is it possible to query DB with EntityChild using standard Spring jpa repositories?
e.g repository.findByChildren(List children)

Thank you