registerBag(

bool migrate(bool $destroy = false, int $lifetime = null) Migrates the current session to a new

string getId() Returns the session ID.

stampNew(int $lifetime = null) Stamps a new session's metadata.

AbstractProxy getSaveHandler() Gets the save handler instance. Return Value AbstractProxy

string getStorageKey() Gets the storage key for this bag.

string getId() Returns the session ID.

open($savePath, $sessionName) {@inheritdoc}

add(string $type, string $message) Adds a flash message for type.

bool has(string $type) Has flash messages for a given type?