Pool::collect

(PECL pthreads >= 2.0.0)

Pool::collect — 回收已完成任务的引用

说明

public int Pool::collect ([ Callable $collector ] )

对于视为垃圾的引用，使用给定的垃圾收集器进行收集

参数

collector

垃圾收集器，它返回一个布尔值表示这个任务是否可以被进行垃圾收集。 仅在极少的情况下需要一个自定义的垃圾收集器。

返回值

池中剩余的待收集的任务数量。

更新日志

版本 说明
v3 collector 参数变为可选参数， 并且返回值改为整数。

范例

Example #1 Pool::collect() 基本用法示例

<?php
$pool = new Pool(4);

for ($i = 0; $i < 15; ++$i) {
    $pool->submit(new class extends Threaded {});
}

while ($pool->collect()); // 直到全部的任务都完成执行之后才会继续下面的代码

$pool->shutdown();

User Contributed Notes

meadowsjared at gmail dot com 15-Mar-2016 04:13
Please note, when using the collect function, it's important that you extend the pool class so you can keep checking for finished threads until they're all done.

<?php
class TestWork extends Threaded {
    protected $complete;
    //$pData is the data sent to your worker thread to do it's job.
    public function __construct($pData){
        //transfer all the variables to local variables
        $this->complete = false;
        $this->testData = $pData;
    }
    //This is where all of your work will be done.
    public function run(){
        usleep(2000000); //sleep 2 seconds to simulate a large job
        $this->complete = true;
    }
    public function isGarbage() {
        return $this->complete;
    }
}
class ExamplePool extends Pool
{
    public $data = array();
    public function process()
    {
        // Run this loop as long as we have
        // jobs in the pool
        while (count($this->work)) {
            $this->collect(function (TestWork $task) {
                // If a task was marked as done
                // collect its results
                if ($task->isGarbage()) {
                    $tmpObj = new stdclass();
                    $tmpObj->complete = $task->complete;
                    //this is how you get your completed data back out [accessed by $pool->process()]
                    $this->data[] = $tmpObj;
                }
                return $task->isGarbage();
            });
        }
        // All jobs are done
        // we can shutdown the pool
        $this->shutdown();
        return $this->data;
    }
}
$pool = new ExamplePool(3);
$testData = 'asdf';
for($i=0;$i<5;$i++) {
    $pool->submit(new TestWork($testData));
}
$retArr = $pool->process(); //get all of the results
echo '<pre>';
print_r($retArr); //return the array of results (and maybe errors)
echo '</pre>';
?>
your dot brother dot t at hotmail dot com 29-Dec-2014 06:33
The example code crashes and made me waste 2 working days
First of all, `Stackable` has no attribute named $worker or it's access method made it inaccessible.

Secondly, `Stackable` also doesn't have `getThreadId()` . It's best practice to use `Thread` class for realization of a thread since it has more control functions. It's better to use `Stackable` for object storage and use it's `run()` as its initialization.

The working example is

<?php
    class MyWork extends Thread {
        protected $complete;

        public function __construct() {
            $this->complete = false;
        }

        public function run() {
            printf(
                "Hello from %s in Thread #%lu\n",
                __CLASS__, $this->getThreadId());
            $this->complete = true;
        }

        public function isComplete() {
            return $this->complete;
        }
    }

    class Something {}

    class MyWorker extends Worker {

        public function __construct(Something $something) {
            $this->something = $something;
        }

        public function run() {
            /** ... **/
        }
    }

    $pool = new Pool(8, \MyWorker::class, [new Something()]);
    $pool->submit(new MyWork());

    usleep(1000);

    $pool->collect(function($work){
        return $work->isComplete();
    });
    var_dump($pool);
?>