IsolateWorkerBase class abstract

Base class for isolate-backed worker objects.

Provides the standard boilerplate shared across single-channel isolate workers:

• An IsolateRpcClient for send/receive communication
• An isReady flag
• A sendRequest guard that rejects calls before initialization
• A dispose implementation that kills the isolate and closes the port

Lifecycle safety

dispose calls IsolateRpcClient.failAllAndDispose synchronously (which internally calls isolate.kill()) before any await. This ensures the background isolate is terminated immediately even if the caller does not await the returned future, preventing use-after-free on native TFLite memory.

Subclasses must:

1. Call await initWorker(spawnFn) during their own initialization to spawn the isolate and complete the handshake.
2. Override workerDisposeOp to specify the dispose operation name (if any).
3. Override dispose() and call await super.dispose() when cleaning up.

Constructors

IsolateWorkerBase()

Properties

hashCode → int

The hash code for this object.

no setter, inherited

isReady → bool

Returns true if the worker has been initialized and is ready for requests.

no setter

rpc → IsolateRpcClient

final

runtimeType → Type

A representation of the runtime type of the object.

no setter, inherited

workerDisposeOp → String?

The name of the operation to send to the isolate when disposing.

no setter

Methods

dispose() → Future<void>

Disposes the worker: fails pending requests, sends workerDisposeOp to the isolate (if non-null), kills the isolate, and closes ports.

disposeGracefully({Duration timeout = const Duration(seconds: 5)}) → Future<void>

Gracefully disposes the worker: sends workerDisposeOp to the isolate as a request and awaits its acknowledgement — giving the isolate a chance to free native resources — before force-killing it via dispose.

initWorker(Future<Isolate> spawnFn(SendPort sendPort), {Duration timeout = const Duration(seconds: 30), String timeoutMessage = 'Worker initialization timed out', void onResponse(dynamic)?, bool markReady = true}) → Future<void>

Spawns the background isolate and completes the handshake.

markInitialized() → void

Marks the worker as initialized and ready for requests.

noSuchMethod(Invocation invocation) → dynamic

Invoked when a nonexistent method or property is accessed.

inherited

sendRequest<T>(String operation, Map<String, dynamic> params) → Future<T>

Sends a typed request to the background isolate.

sendRequestUnchecked<T>(String operation, Map<String, dynamic> params) → Future<T>

Sends a typed request directly to the background isolate, bypassing the isReady guard.

toString() → String

A string representation of this object.

inherited

Operators

operator ==(Object other) → bool

The equality operator.

inherited