... and yes, as a Java developer, I use Guava once in a while and I do JavaScript as part of my job as well and I do appreciate first-class function.
Typically the problems that functional features solve are filtering and transformation and yet most often than not I happen to solve them at the SQL layer (be it JPQL or straight up SQL).
var rules =
AppDomain.CurrentDomain.GetAssemblies
.SelectMany(a => a.GetTypes())
.Where(t => typeof(ISecurityRule).IsAssignableFrom(t))
.Select(t => Activator.CreateInstance() as ISecurityRule)
.OrderBy(r => r.Priority);
var allowed = rules.First(r => r.Check(someObject) != null);
//Check returns null when a rule isn't relevant to the object being checked
Java has AOP and extensively use Annotations (Attributes in .NET) and the approach there is definitely heavier than what you wrote above.