Package com.ultikits.ultitools.utils

Class SessionDedupeLedger

java.lang.Object

com.ultikits.ultitools.utils.SessionDedupeLedger

All Implemented Interfaces:

DedupeLedger

final class SessionDedupeLedger
extends Object
implements DedupeLedger

The DedupeLedger every inbound handler of the framework shares (plan 22-21, D-17 as narrowed by S-52, S-59): the command-id set and the receipts live in the current session's CommandDedupeSet, and persistNow() writes them, with the outbox, to cloud-outbox.json through the session's CloudStateStore.

Lifetime. One instance lives as long as the plugin is enabled, so the monitor stays the same across reconnects and across the session replacements of a login or logout. Each call asks the SessionDedupeLedger.Target supplier for the state of the session that is current at that moment; with no adopted credential (no target, or one without a store) firstSeen(java.lang.String) reports every id as new, no receipt exists and persistNow() fails, which the callers already treat as "continue with what is in memory".

Locks. Callers hold this ledger's monitor around a mutation and its persistence. persistNow() then takes the store's JVM-wide write lock and, inside it, the dedupe set's leaf monitor; it never takes a session monitor, so it cannot invert the lock order of CloudSession (S-32, S-37). It is synchronous and runs on the thread that handles the request -- the agent thread or the player-link handler thread, never the server thread. A module may complete its player-link result on any thread, the server thread included; PlayerLinkChannel moves the persistence of that result onto the player-link handler thread first.

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
(package private) static final class	SessionDedupeLedger.Target	The state of one session: its id set, its state file and the server id the file is written for.

Field Summary

Fields

Modifier and Type	Field	Description
private final Supplier<SessionDedupeLedger.Target>	target

Constructor Summary

Constructors

Constructor	Description
SessionDedupeLedger(Supplier<SessionDedupeLedger.Target> target)

Method Summary

Modifier and Type	Method	Description
boolean	firstSeen(String id)	Records a previously unseen id in memory, subject to retention bounds.
(package private) static SessionDedupeLedger	fixed(CommandDedupeSet dedupe, CloudStateStore store, String serverId)
void	persistNow()	Writes the ids, their receipts and the outbox now, under the store's write lock.
com.google.gson.JsonObject	receiptFor(String id)	Looks up a completion result for replay, without invoking its handler again.
void	recordReceipt(String id, com.google.gson.JsonObject receipt)	Records the receipt with its id.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Details

target

private final Supplier<SessionDedupeLedger.Target> target

Constructor Details

SessionDedupeLedger

SessionDedupeLedger(Supplier<SessionDedupeLedger.Target> target)

Parameters:

target - supplies the current session's state, or null while no credential is adopted

Method Details

fixed

static SessionDedupeLedger fixed(CommandDedupeSet dedupe,
 CloudStateStore store,
 String serverId)

Parameters:

dedupe - the id set

store - the state file writer, or null for an in-memory ledger

serverId - the linked server's id

Returns:

a ledger bound to exactly that state

firstSeen

public boolean firstSeen(String id)

Description copied from interface: DedupeLedger

Records a previously unseen id in memory, subject to retention bounds.

Specified by:

firstSeen in interface DedupeLedger

Parameters:

id - the request envelope ULID

Returns:

true for a newly recorded id, false for an unexpired duplicate

persistNow

public void persistNow()
                throws IOException

Writes the ids, their receipts and the outbox now, under the store's write lock.

Specified by:

persistNow in interface DedupeLedger

Throws:

IOException - when no store is adopted or the write fails; the dirty flags then stay set, so the next periodic flush retries

receiptFor

public com.google.gson.JsonObject receiptFor(String id)

Description copied from interface: DedupeLedger

Looks up a completion result for replay, without invoking its handler again.

Specified by:

receiptFor in interface DedupeLedger

Parameters:

id - the completed-message envelope ULID

Returns:

the recorded result payload, or null when absent; callers must not mutate it

recordReceipt

public void recordReceipt(String id,
 com.google.gson.JsonObject receipt)

Records the receipt with its id. A receipt larger than CommandDedupeSet.MAX_RECEIPT_BYTES is not recorded and logs one WARNING: the reply is still sent, and a redelivery of that id asks the module again.

Specified by:

recordReceipt in interface DedupeLedger

Parameters:

id - the completed-message envelope ULID

receipt - the result payload; callers must not mutate it after recording