FramesLost

Frames from one admitted member were routed and are gone: the reason a Room.incomingFrom flow failed instead of delivering them (#2802).

A per-member stream never loses a frame silently. It delivers every frame it held, in arrival order, and then either completes — the member's admission ended, or there is no current admission to read — or fails with this, saying how much was lost and which side of the claim it happened on.

dropped is the number of frames known lost when the stream ended. claimed says which case it was: false — nothing had called Room.incomingFrom for this admission before its inbox overflowed, so the room released what it held, including the member's first frames; true — a collector had claimed the inbox and fell behind it, so the flow delivered everything it held and then failed here rather than make the room's routing wait. One type, because the consumer's answer to both is the same.

Terminal for the admission. Every later collection or claim of that member's frames fails the same way, and nothing restarts the stream. Treat the member as lost — let its session drop and re-join, which is a new admission with a fresh inbox — rather than reading on.

A RuntimeException rather than an IllegalStateException so that it stays distinguishable from the IllegalStateException a second concurrent collection throws, which is a bug in the collector rather than a fact about the member's frames.