protected ConfigDef populateConfigDef(String typeConfig) {
            final ConfigDef configDef = initialConfigDef();
            try {
                configDefsForClass(typeConfig)
                        .forEach(entry -> configDef.define(entry.getValue()));

            } catch (ConfigException e) {
                if (requireFullConfig) {
                    throw e;
                } else {
                    return null;
                }
            }
            return configDef;
        }
Populates the ConfigDef according to the configs returned from {@code configs()} method of class
named in the {@code ...type} parameter of the {@code props}.
connect/runtime/src/main/java/org/apache/kafka/connect/runtime/ConnectorConfig.java