KeyStoreTxn<K, V, T> class abstract

Handle passed to a transaction(body) callback. Within the body, mutations recorded via this handle are buffered in memory; reads via this handle see the buffered state on top of the underlying keystore. At successful body completion the buffered mutations are applied to the keystore (and changes events fire). If the body throws, the buffered mutations are dropped and no events fire.

Hive's atomicity is best-effort: writes are durable per underlying box flush, but a process crash mid-commit can leave the keystore with a subset of the buffered ops applied. A future SQL backend will provide true atomicity via BEGIN IMMEDIATE / COMMIT.

Lifetime: the handle is valid only for the duration of the body callback. Calling any method on it after transaction(...) returns is undefined behaviour.

Constructors

KeyStoreTxn()

Properties

hashCode → int
The hash code for this object.
no setterinherited
runtimeType → Type
A representation of the runtime type of the object.
no setterinherited

Methods

exists(K key) → Future<bool>
Returns true if key would resolve to a value within this transaction's view. Reflects buffered writes / deletions on top of the underlying keystore.
get(K key) → Future<V?>
Returns the value key would resolve to within this transaction's view. Reflects any buffered write (the buffered value), buffered deletion (null), or otherwise the value already in the underlying keystore.
noSuchMethod(Invocation invocation) → dynamic
Invoked when a nonexistent method or property is accessed.
inherited
put(K key, V value, T metadata) → Future<void>
Buffer a write of value (with metadata) under key. Visible to subsequent get / exists calls on the same handle; applied to the underlying keystore at commit.
remove(K key) → Future<void>
Buffer a deletion of key. Subsequent exists returns false; subsequent get returns null. The actual delete happens at commit.
toString() → String
A string representation of this object.
inherited

Operators

operator ==(Object other) → bool
The equality operator.
inherited