Package com.tnsai.idempotency

Class InMemoryIdempotencyStore

java.lang.Object

com.tnsai.idempotency.InMemoryIdempotencyStore

All Implemented Interfaces:

IdempotencyStore

public final class InMemoryIdempotencyStore
extends Object
implements IdempotencyStore

Default IdempotencyStore — process-local, ephemeral, no external dependencies (issue #91). Suitable for single-process deployments and tests; production multi-process deployments should pick a Redis or Postgres adapter (separate follow-up PRs) so dedup survives process restarts and works across instances.

Eviction is lazy: an expired entry stays in the map until the next get(String) for that key, at which point it is removed and the lookup returns empty. This keeps the put/get path lock-free at the cost of one map slot per expired-but-not-yet-touched key. For deployments that hold a steady set of keys, that's free; for deployments where the key space grows unboundedly, prefer the external-store adapters which can scan + evict in the background.

Since:

0.5.0 (issue #91)

Constructor Summary

Constructors

Constructor	Description
InMemoryIdempotencyStore()

Method Summary

Modifier and Type	Method	Description
Optional<IdempotencyEntry>	get(String key)	Look up a cached entry.
void	invalidate(String key)	Remove the entry for key if any.
void	put(String key, IdempotencyEntry entry, Duration ttl)	Store an entry under key with the given TTL.
int	size()	Approximate entry count.

Methods inherited from class java.lang.Object

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

Constructor Details

InMemoryIdempotencyStore

public InMemoryIdempotencyStore()

Method Details

get

public Optional<IdempotencyEntry> get(String key)

Description copied from interface: IdempotencyStore

Look up a cached entry. Returns empty when no entry exists OR when the entry's TTL has elapsed.

Specified by:

get in interface IdempotencyStore

put

public void put(String key,
 IdempotencyEntry entry,
 Duration ttl)

Description copied from interface: IdempotencyStore

Store an entry under key with the given TTL. Subsequent IdempotencyStore.get(java.lang.String) calls within the TTL window return this entry. Overwrites any prior entry for the same key.

Specified by:

put in interface IdempotencyStore

invalidate

public void invalidate(String key)

Description copied from interface: IdempotencyStore

Remove the entry for key if any. No-op if the key is not present.

Specified by:

invalidate in interface IdempotencyStore

size

public int size()

Description copied from interface: IdempotencyStore

Approximate entry count. Intended for monitoring / smoke-testing ("cache has grown to 10M entries, check your TTL"). Implementations may return an eventually-consistent snapshot.

Specified by:

size in interface IdempotencyStore