RequestCacheAwareFilter

private void handleSpringSecurityException(HttpServletRequest request, HttpServletResponse response, FilterChain chain, RuntimeException exception) throws IOException, ServletException {
    if (exception instanceof AuthenticationException) {
        this.handleAuthenticationException(request, response, chain, (AuthenticationException)exception);
    } else if (exception instanceof AccessDeniedException) {
        this.handleAccessDeniedException(request, response, chain, (AccessDeniedException)exception);
    }

}

private void handleAccessDeniedException(HttpServletRequest request, HttpServletResponse response,
		FilterChain chain, AccessDeniedException exception) throws ServletException, IOException {
	Authentication authentication = SecurityContextHolder.getContext().getAuthentication();
	boolean isAnonymous = this.authenticationTrustResolver.isAnonymous(authentication);
	if (isAnonymous || this.authenticationTrustResolver.isRememberMe(authentication)) {
		if (logger.isTraceEnabled()) {
			logger.trace(LogMessage.format("Sending %s to authentication entry point since access is denied",
					authentication), exception);
		}
		sendStartAuthentication(request, response, chain,
				new InsufficientAuthenticationException(
						this.messages.getMessage("ExceptionTranslationFilter.insufficientAuthentication",
								"Full authentication is required to access this resource")));
	}
	else {
		if (logger.isTraceEnabled()) {
			logger.trace(
					LogMessage.format("Sending %s to access denied handler since access is denied", authentication),
					exception);
		}
		this.accessDeniedHandler.handle(request, response, exception);
	}
}

protected void sendStartAuthentication(HttpServletRequest request, HttpServletResponse response, FilterChain chain,
		AuthenticationException reason) throws ServletException, IOException {
	// SEC-112: Clear the SecurityContextHolder's Authentication, as the
	// existing Authentication is no longer considered valid
	SecurityContextHolder.getContext().setAuthentication(null);
	this.requestCache.saveRequest(request, response);
	this.authenticationEntryPoint.commence(request, response, reason);
}

public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain) throws IOException, ServletException {
    HttpServletRequest wrappedSavedRequest = this.requestCache.getMatchingRequest((HttpServletRequest)request, (HttpServletResponse)response);
    chain.doFilter((ServletRequest)(wrappedSavedRequest != null ? wrappedSavedRequest : request), response);
}