UlidFactory class

Generates Ulid instances.

By default every next call draws a fresh 80-bit random value. With monotonic set, a call whose timestamp does not exceed the last one (same millisecond, or the clock went backwards) reuses the last timestamp and increments the last random value instead, so IDs from this factory always sort in call order (see the ULID spec's monotonicity recommendation).

monotonicRandomBits keeps that many least-significant bits genuinely random on every call instead of incrementing them; only the remaining, most-significant 80 - N bits act as the counter. Ordering is unaffected, but a bigger tail means a smaller, sooner-overflowing counter. monotonicBufferBits clears that many most-significant bits of every freshly drawn random value, guaranteeing the counter that amount of headroom before it can overflow (1 guarantees at least half of the counter's range is free; this is the usual practical setting).

Counter overflow throws a StateError by default; set incrementMillisOnOverflow to advance the timestamp by 1ms and draw a fresh random value instead.

A single UlidFactory instance is not safe to share across isolates, but is safe to reuse across calls within the same isolate.

Constructors

UlidFactory({bool monotonic = false, bool incrementMillisOnOverflow = false, int monotonicRandomBits = 0, int monotonicBufferBits = 0, Random? random})

Creates a new UlidFactory.

Properties

hashCode → int

The hash code for this object.

no setter, inherited

runtimeType → Type

A representation of the runtime type of the object.

no setter, inherited

Methods

next({int? millis}) → Ulid

Creates a new Ulid instance.

noSuchMethod(Invocation invocation) → dynamic

Invoked when a nonexistent method or property is accessed.

inherited

toString() → String

A string representation of this object.

inherited

Operators

operator ==(Object other) → bool

The equality operator.

inherited