void enrich(ConfigDef newDef) {
            Object aliases = ConfigDef.parseType(aliasConfig, props.get(aliasConfig), Type.LIST);
            if (!(aliases instanceof List)) {
                return;
            }

            LinkedHashSet<?> uniqueAliases = new LinkedHashSet<>((List<?>) aliases);
            for (Object o : uniqueAliases) {
                if (!(o instanceof String)) {
                    throw new ConfigException("Item in " + aliasConfig + " property is not of "
                            + "type String");
                }
                String alias = (String) o;
                final String prefix = aliasConfig + "." + alias + ".";
                final String group = aliasGroup + ": " + alias;
                int orderInGroup = 0;

                final String typeConfig = prefix + "type";
                final ConfigDef.Validator typeValidator = ConfigDef.LambdaValidator.with(
                    (String name, Object value) -> {
                        validateProps(prefix);
                        // The value will be null if the class couldn't be found; no point in performing follow-up validation
                        if (value != null) {
                            getConfigDefFromConfigProvidingClass(typeConfig, (Class<?>) value);
                        }
                    },
                    () -> "valid configs for " + alias + " " + aliasKind.toLowerCase(Locale.ENGLISH));
                newDef.define(typeConfig, Type.CLASS, ConfigDef.NO_DEFAULT_VALUE, typeValidator, Importance.HIGH,
                        "Class for the '" + alias + "' " + aliasKind.toLowerCase(Locale.ENGLISH) + ".", group, orderInGroup++, Width.LONG,
                        baseClass.getSimpleName() + " type for " + alias,
                        Collections.emptyList(), new ClassRecommender());

                final ConfigDef configDef = populateConfigDef(typeConfig);
                if (configDef == null) continue;
                newDef.embed(prefix, group, orderInGroup, configDef);
            }
        }
Add the configs for this alias to the given {@code ConfigDef}.
connect/runtime/src/main/java/org/apache/kafka/connect/runtime/ConnectorConfig.java