| | |
|---|
| | | return; |
|---|
| | | } |
|---|
| | | |
|---|
| | | enableService(); |
|---|
| | | sessionGeneration++; |
|---|
| | | |
|---|
| | | /* |
|---|
| | | * The flag is cleared before the session is started, where disable() sets it before |
|---|
| | | * stopping one: enableService() ends with startListenService(), so the listener it |
|---|
| | | * starts can list a delivery and hand it to a replay thread while this method is |
|---|
| | | * still running. A replay thread which reads a flag that still says "disabled" |
|---|
| | | * gives the change up at the top of its replay loop, and abandonReplay() does not |
|---|
| | | * ask for it again - a domain on its way down owns its session - so the change is |
|---|
| | | * left listed, uncommitted and owned by nobody. Nothing would replay it: the |
|---|
| | | * replication server only sends it again over a session which is restarted, so this |
|---|
| | | * domain's ServerState, and every change which depends on that one, would be held |
|---|
| | | * back for as long as the session lives. |
|---|
| | | */ |
|---|
| | | disabled = false; |
|---|
| | | boolean started = false; |
|---|
| | | try |
|---|
| | | { |
|---|
| | | enableService(); |
|---|
| | | sessionGeneration++; |
|---|
| | | started = true; |
|---|
| | | } |
|---|
| | | finally |
|---|
| | | { |
|---|
| | | if (!started) |
|---|
| | | { |
|---|
| | | /* |
|---|
| | | * The other half of the same invariant: a domain whose session could not be |
|---|
| | | * started owns that session the way a disabled one does, so the flag goes back |
|---|
| | | * where it was rather than leave the replay threads believing there is a session |
|---|
| | | * of theirs to restart. |
|---|
| | | */ |
|---|
| | | disabled = true; |
|---|
| | | } |
|---|
| | | } |
|---|
| | | } |
|---|
| | | } |
|---|
| | | |
|---|
