code: public final boolean isAllowedOrigin(final Origin origin) {
  
          	if (allowAnyOrigin)
                  	return true;
  		
  		if (origin == null)
  			return false;
  		
  		if (allowedOrigins.contains(origin))
  			return true;
  			
  		else if (allowSubdomains)
  			return isAllowedSubdomainOrigin(origin);
  		
  		return false;
  	}
docs: Helper method to check whether requests from the specified origin
  must be allowed. This is done by looking up {@link #allowAnyOrigin}
  and {@link #allowedOrigins} as well as the {@link #allowSubdomains}
  setting.
  
  @param origin The origin as reported by the web client (browser),
  {@code null} if unknown.
  
  @return {@code true} if the origin is allowed, else {@code false}.