public boolean isValid()

in src/main/java/org/apache/sling/jcr/resource/internal/JcrSystemUserValidator.java [168:226]
53 lines of code
11 McCabe index (conditional complexity)

    public boolean isValid(Iterable<String> servicePrincipalNames, String serviceName, String subServiceName) {
        if (cycleDetection.get()) {
            // We are being asked to valid our own service user - hence, allow.
            return true;
        }
        if (servicePrincipalNames == null) {
            log.debug("The provided service principal names are null");
            return false;
        }
        if (!allowOnlySystemUsers) {
            log.debug("There is no enforcement of JCR system users, therefore service principal names '{}' are valid", servicePrincipalNames);
            return true;
        }

        Session session = null;
        UserManager userManager = null;
        Set<String> invalid = new HashSet<>();
        try {
            for (final String pName : servicePrincipalNames) {
                if (validPrincipalNames.contains(pName)) {
                    log.debug("The provided service principal name '{}' has been already validated and is a known JCR system user", pName);
                } else {
                    if (session == null) {
                        /*
                         * We have to prevent a cycle if we are trying to login ourselves
                         */
                        cycleDetection.set(true);
                        try {
                            session = repository.loginService(VALIDATION_SERVICE_USER, null);
                        } finally {
                            cycleDetection.set(false);
                        }
                        if (session instanceof JackrabbitSession) {
                            userManager = ((JackrabbitSession) session).getUserManager();
                        } else {
                            log.debug("Unable to validate service user principals, JackrabbitSession expected.");
                            return false;
                        }
                    }

                    Authorizable authorizable = userManager.getAuthorizable(() -> pName);
                    if (isValidSystemUser(authorizable)) {
                        validPrincipalNames.add(pName);
                        log.debug("The provided service principal name {} is a known JCR system user", pName);
                    } else {
                        log.warn("The provided service principal name '{}' is not a known JCR system user id and therefore not allowed in the Sling Service User Mapper.", pName);
                        invalid.add(pName);
                    }
                }
            }
        } catch (final RepositoryException e) {
            log.warn("Could not get user information", e);
        } finally {
            if (session != null) {
                session.logout();
            }
        }
        return invalid.isEmpty();
    }