@Override
protected void doFilterInternal(HttpServletRequest request,
		HttpServletResponse response, FilterChain filterChain)
		throws ServletException, IOException {
	request.setAttribute(SESSION_REPOSITORY_ATTR, this.sessionRepository);
	SessionRepositoryRequestWrapper wrappedRequest = new SessionRepositoryRequestWrapper(
			request, response, this.servletContext);
	SessionRepositoryResponseWrapper wrappedResponse = new SessionRepositoryResponseWrapper(
			wrappedRequest, response);
	try {
		filterChain.doFilter(wrappedRequest, wrappedResponse);
	}
	finally {
		wrappedRequest.commitSession();
	}
}

private final class SessionRepositoryResponseWrapper
		extends OnCommittedResponseWrapper {
	private final SessionRepositoryRequestWrapper request;
	/**
	 * Create a new {@link SessionRepositoryResponseWrapper}.
	 * @param request the request to be wrapped
	 * @param response the response to be wrapped
	 */
	SessionRepositoryResponseWrapper(SessionRepositoryRequestWrapper request,
			HttpServletResponse response) {
		super(response);
		if (request == null) {
			throw new IllegalArgumentException("request cannot be null");
		}
		this.request = request;
	}
	@Override
	protected void onResponseCommitted() {
		this.request.commitSession();
	}
}