/** * Returns the mapping of external names to standard names for a group. * <p> * External names are used to map names used by external systems to the standard name used here. * There can be multiple groups of mappings to external systems, * For example, the mapping used by FpML may differ from that used by Bloomberg. * <p> * The result provides mapping between the external name and the standard name. * * @param group the group name to find external names for * @return the map of external names for the group * @throws IllegalArgumentException if the group is not found */ public ExternalEnumNames<T> externalNames(String group) { ImmutableMap<String, String> externals = externalNames.get(group); if (externals == null) { throw new IllegalArgumentException(type.getSimpleName() + " group not found: " + group); } return new ExternalEnumNames<>(this, group, externals); }