Javadoc
Request an implementation of a particular interface.
If the passed-in interface is
QueryableIndex or
StorageAdapter, then this method behaves
identically to
#asQueryableIndex() or
#asStorageAdapter(). Other interfaces are only
expected to be requested by callers that have specific knowledge of extra features provided by specific
segment types. For example, an extension might provide a custom Segment type that can offer both
StorageAdapter and some new interface. That extension can also offer a Query that uses that new interface.
Implementations which accept classes other than
QueryableIndex or
StorageAdapter are limited
to using those classes within the extension. This means that one extension cannot rely on the `Segment.as`
behavior of another extension.