presto-plugin-toolkit/src/main/java/io/prestosql/plugin/base/security/FileBasedSystemAccessControlRules.java/FileBasedSystemAccessControlRules/getPrincipalUserMatchRules
class FileBasedSystemAccessControlRules:    public Optional<List<PrincipalUserMatchRule>> getPrincipalUserMatchRules()
    {
        return principalUserMatchRules;
    }