String storeName = i.next();
SessionStore store = requestContext.getSessionConfig().getStores().getStore(storeName);
if (isApplicableToCommit(store, commitHeaders)) {
Map<String, Object> storeAttrs = emptyMap();
store.commit(storeAttrs, sessionID, new StoreContextImpl(storeName));
i.remove(); // 清除clearing标记,以防重复clear
} else if (!commitHeaders) {
log.warn("Session was cleared, but the data in {}[id={}] may not be cleared, " +
"because the response has already been committed.", store.getClass().getSimpleName(), storeName);
}