一个可能的解决方案是定义自己的datatypefactory并使用它。我这样做是为了支持postgresqljsonb数据类型，类似的东西也可以用于mysql。

class NewPostgresqlDataTypeFactory : PostgresqlDataTypeFactory() {
    override fun createDataType(sqlType: Int, sqlTypeName: String?): DataType {
        return when (sqlTypeName) {
            "jsonb" -> return JsonbDataType()
            else -> super.createDataType(sqlType, sqlTypeName)
        }
    }

    class JsonbDataType : AbstractDataType("jsonb", Types.OTHER, String::class.java, false) {
        override fun typeCast(obj: Any?): Any {
            return obj.toString()
        }

        override fun getSqlValue(column: Int, resultSet: ResultSet): Any {
            return resultSet.getString(column)
        }

        override fun setSqlValue(value: Any?, column: Int, statement: PreparedStatement) {
            val jsonObj = PGobject()
            jsonObj.type = "json"
            jsonObj.value = value?.toString()
            statement.setObject(column, jsonObj)
        }
    }
}

如果有人需要，这是@aleksi的postgresql jsonb数据类型解决方案的java版本：

import org.dbunit.dataset.datatype.AbstractDataType;
import org.dbunit.dataset.datatype.DataType;
import org.dbunit.dataset.datatype.DataTypeException;
import org.dbunit.dataset.datatype.TypeCastException;
import org.dbunit.ext.postgresql.PostgresqlDataTypeFactory;
import org.postgresql.util.PGobject;

import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Types;

public class NewPostgresqlDataTypeFactory extends PostgresqlDataTypeFactory {
    @Override
    public DataType createDataType(int sqlType, String sqlTypeName) throws DataTypeException {
        if (sqlTypeName.equals("jsonb")) {
            return new JsonbDataType();
        } else {
            return super.createDataType(sqlType, sqlTypeName);
        }
    }

    public static class JsonbDataType extends AbstractDataType {

        public JsonbDataType() {
            super("jsonb", Types.OTHER, String.class, false);
        }

        @Override
        public Object typeCast(Object obj) throws TypeCastException {
            return obj.toString();
        }

        @Override
        public Object getSqlValue(int column, ResultSet resultSet) throws SQLException, TypeCastException {
            return resultSet.getString(column);
        }

        @Override
        public void setSqlValue(Object value,
                                int column,
                                PreparedStatement statement) throws SQLException, TypeCastException {
            final PGobject jsonObj = new PGobject();
            jsonObj.setType("json");
            jsonObj.setValue(value == null ? null : value.toString());

            statement.setObject(column, jsonObj);
        }
    }
}