haxe-concurrent - cross-platform concurrency support
- What is it?
hx.concurrent.atomic
packagehx.concurrent.collection
packagehx.concurrent.executor
packagehx.concurrent.event
packagehx.concurrent.lock
packagehx.concurrent.thread
package- Installation
- Using the latest code
- License
- Alternatives
What is it?
A haxelib that provides some basic platform agnostic concurrency support.
All classes are located in the package hx.concurrent
or below.
The library has been extensively unit tested (over 400 individual test cases) on the targets C++, C#, Eval, Flash, HashLink, Java, JavaScript (Node.js and PhantomJS), Lua, Neko, PHP 7 and Python 3.
Note:
- When targeting Flash the option
-swf-version 11.5
(or higher) must be specified, otherwise you will getClass flash.concurrent::Condition could not be found.
- When targeting C# the option
-D net-ver=45
must be specified, otherwise you may geterror CS0234: The type or namespace name 'Volatile' does not exist in the namespace 'System.Threading'. Are you missing an assembly reference?
- Multi-threading/locking support in Eval is broken, see some of the unresolved issues:
- https://github.com/HaxeFoundation/haxe/issues/8524
- https://github.com/HaxeFoundation/haxe/issues/8525
Haxe compatibility
haxe-concurrent | Haxe |
---|---|
1.0.0 to 1.2.0 | 3.2.1 or higher |
2.0.0 to 2.1.3 | 3.4.2 or higher |
3.0.0 or higher | 4.0.5 or higher |
4.0.0 or higher | 4.2.0 or higher |
The hx.concurrent.atomic
package
The hx.concurrent.atomic package contains mutable value holder classes that allow for thread.safe manipulation:
The hx.concurrent.collection
package
The hx.concurrent.collection package contains thread-safe implementations of different types of collections:
The hx.concurrent.executor
package
The hx.concurrent.executor package contains Executor implementations that allow to execute functions concurrently and to schedule tasks for later/repeated execution.
On platform with the thread support (C++, C#, Eval, HashLink, Neko, Python, Java) threads are used to realize true concurrent execution, on other
platforms haxe.Timer
is used to at least realize async execution.
import hx.concurrent.executor.Schedule;
import hx.concurrent.executor.Executor;
class Test {
static function main() {
var executor = Executor.create(3); // <- 3 means to use a thread pool of 3 threads on platforms that support threads
// depending on the platform either a thread-based or timer-based implementation is returned
// define a function to be executed concurrently/async/scheduled (return type can also be Void)
var myTask = function():Date {
trace("Executing...");
return Date.now();
}
// submit 10 tasks each to be executed once asynchronously/concurrently as soon as possible
for (i in 0...10) {
executor.submit(myTask);
}
executor.submit(myTask, ONCE(2000)); // async one-time execution with a delay of 2 seconds
executor.submit(myTask, FIXED_RATE(200)); // repeated async execution every 200ms
executor.submit(myTask, FIXED_DELAY(200)); // repeated async execution 200ms after the last execution
executor.submit(myTask, HOURLY(30)); // async execution 30min after each full hour
executor.submit(myTask, DAILY(3, 30)); // async execution daily at 3:30
executor.submit(myTask, WEEKLY(SUNDAY, 3, 30)); // async execution Sundays at 3:30
// submit a task and keep a reference to it
var future = executor.submit(myTask, FIXED_RATE(200));
// check if a result is already available
switch (future.result) {
case VALUE(value, time, _): trace('Successfully execution at ${Date.fromTime(time)} with result: $value');
case FAILURE(ex, time, _): trace('Execution failed at ${Date.fromTime(time)} with exception: $ex');
case PENDING(_): trace("No result yet...");
}
// check if the task is scheduled to be executed (again) in the future
if (!future.isStopped) {
trace('The task is scheduled for further executions with schedule: ${future.schedule}');
}
// cancel any future execution of the task
future.cancel();
}
}
The hx.concurrent.event
package
The hx.current.event package contains classes for type-safe event dispatching.
import hx.concurrent.event.AsyncEventDispatcher;
import hx.concurrent.event.SyncEventDispatcher;
import hx.concurrent.Future;
import hx.concurrent.executor.Executor;
class Test {
static function main() {
/**
* create a dispatcher that notifies listeners/callbacks synchronously in the current thread
*/
var syncDispatcher = new SyncEventDispatcher<String>(); // events are of type string
// create event listener
var onEvent = function(event:String):Void {
trace('Received event: $event');
}
syncDispatcher.subscribe(onEvent);
// notify all registered listeners synchronously,
// meaning this method call blocks until all listeners are finished executing
syncDispatcher.fire("Hey there");
/**
* create a dispatcher that notifies listeners asynchronously using an executor
*/
var executor = Executor.create(5); // thread-pool with 5 threads
var asyncDispatcher = new AsyncEventDispatcher<String>(executor);
// create event listener
var onAsyncEvent = function(event:String):Void {
trace('Received event: $event');
}
// notify all registered listeners asynchronously,
// meaning this method call returns immediately
asyncDispatcher.fire("Hey there");
// fire another event and get notified when all listeners where notified
var future = asyncDispatcher.fire("Boom");
asyncDispatcher.subscribe(onAsyncEvent);
future.onCompletion(result -> {
switch(result) {
case VALUE(count, _): trace('$count listeners were successfully notified');
case FAILURE(ex, _): trace('Event could not be delivered because of: $ex');
case PENDING(_): trace("Nothing is happening");
}
});
}
}
The hx.concurrent.lock
package
The hx.concurrent.lock package contains lock implementations for different purposes:
The hx.concurrent.thread
package
The hx.concurrent.thread package contains classes for platforms supporting threads:
-
ThreadPool - basic thread-pool implementation supporting C++, C#, HashLink, Neko, Java and Python. For advanced concurrency or cross-platform requirements use Executor instead.
import hx.concurrent.thread.*; class Test { static function main() { var pool = new ThreadPool(4); // 4 concurrent threads pool.submit(function(ctx:ThreadContext) { // do some work here }); pool.awaitCompletion(30 * 1000); // wait 30 seconds for all submitted tasks to be processed pool.cancelPendingTasks(); // cancels execution of all currently queued tasks // initiate graceful stop of all running threads, i.e. they finish the current tasks they process // execution of all other queued tasks is cancelled pool.stop(); } }
Installation
- install the library via haxelib using the command:
haxelib install haxe-concurrent
-
use in your Haxe project
- for OpenFL/Lime projects add
<haxelib name="haxe-concurrent" />
to your project.xml - for free-style projects add
-lib haxe-concurrent
toyour *.hxml
file or as command line option when running the Haxe compiler
- for OpenFL/Lime projects add
Using the latest code
Using haxelib git
haxelib git haxe-concurrent https://github.com/vegardit/haxe-concurrent main D:\haxe-projects\haxe-concurrent
Using Git
- check-out the main branch
git clone https://github.com/vegardit/haxe-concurrent --branch main --single-branch D:\haxe-projects\haxe-concurrent
- register the development release with Haxe
haxelib dev haxe-concurrent D:\haxe-projects\haxe-concurrent
License
All files are released under the Apache License 2.0.
Individual files contain the following tag instead of the full license text:
SPDX-License-Identifier: Apache-2.0
This enables machine processing of license information based on the SPDX License Identifiers that are available here: https://spdx.org/licenses/.
Alternatives
Other libraries addressing concurrency/parallelism:
- https://github.com/botsman/hxasync - async/await implementation for Python and JavaScript
- https://github.com/haxetink/tink_concurrent - abstraction layer over the target-specific concurrency APIs
- https://github.com/thomasuster/haxe-threadpool (2017) thread pool implementation for C++, Neko, Java, C# and Python
- https://github.com/Rezmason/Golems (2017)
- https://github.com/kevinresol/filelock (2016)
- https://github.com/Blank101/haxe-concurrency (2015)
- https://github.com/TiVo/activity (2015)
- https://gist.github.com/hamaluik/80fb81f84ecedbe2a6af (2014) - cross platform API but only uses real threads on C++ and Neko, otherwise single threaded blocking execution
- https://github.com/zjnue/hxworker (2014)