protected static boolean applies()

in mailbox/api/src/main/java/org/apache/james/mailbox/acl/UnionMailboxACLResolver.java [129:214]
61 lines of code
20 McCabe index (conditional complexity)

    protected static boolean applies(EntryKey aclKey, EntryKey queryKey, Username resourceOwner) {
        final String aclKeyName = aclKey.getName();
        final NameType aclKeyNameType = aclKey.getNameType();
        if (SpecialName.anyone.name().equals(aclKeyName)) {
            /* this works also for unauthenticated users */
            return true;
        } else if (queryKey != null) {
            String queryUserOrGroupName = queryKey.getName();
            switch (queryKey.getNameType()) {
            case user:
                /* Authenticated users */
                switch (aclKeyNameType) {
                case special:
                    if (SpecialName.authenticated.name().equals(aclKeyName)) {
                        /* non-null query user is viewed as authenticated */
                        return true;
                    } else if (SpecialName.owner.name().equals(aclKeyName)) {
                        return queryUserOrGroupName.equals(resourceOwner.asString());
                    } else {
                        /* should not happen unless the parent if is changed */
                        throw new IllegalStateException("Unexpected " + SpecialName.class.getName() + "." + aclKeyName);
                    }
                case user:
                    return aclKeyName.equals(queryUserOrGroupName);
                default:
                    throw new IllegalStateException("Unexpected " + NameType.class.getName() + "." + aclKeyNameType);
                }
            case group:
                /* query is a group */
                switch (aclKeyNameType) {
                case special:
                    if (SpecialName.authenticated.name().equals(aclKeyName)) {
                        /*
                         * see the javadoc comment on listRights()
                         */
                        return true;
                    } else if (SpecialName.owner.name().equals(aclKeyName)) {
                        return false;
                    } else {
                        /* should not happen unless the parent if is changed */
                        throw new IllegalStateException("Unexpected " + SpecialName.class.getName() + "." + aclKeyName);
                    }
                case user:
                    /* query groups cannot match ACL users */
                    return false;
                case group:
                    return aclKeyName.equals(queryUserOrGroupName);
                default:
                    throw new IllegalStateException("Unexpected " + NameType.class.getName() + "." + aclKeyNameType);
                }
            case special:
                /* query is a special name */
                switch (aclKeyNameType) {
                case special:
                    /*
                     * query owner matches authenticated because owner will
                     * be resolved only if the user is authenticated
                     */
                    if (aclKeyName.equals(queryUserOrGroupName)) {
                        /*
                         * authenticated matches authenticated and owner matches
                         * owner
                         */
                        return true;
                    } else {
                        /*
                         * query owner matches authenticated because owner will
                         * be resolved only if the user is authenticated
                         */
                        return SpecialName.owner.name().equals(queryUserOrGroupName) && SpecialName.authenticated.name().equals(aclKeyName);
                    }
                case user:
                case group:
                    /* query specials cannot match ACL users or groups */
                    return false;
                default:
                    throw new IllegalStateException("Unexpected " + NameType.class.getName() + "." + aclKeyNameType);
                }
            default:
                throw new IllegalStateException("Unexpected " + NameType.class.getName() + "." + queryKey.getNameType());
            }
        } else {
            /* non-anyone ACL keys do not match non-authenticated queries */
            return false;
        }
    }