PHP7 Pool

Creational/Pool/Processor.php

@@ -1,51 +0,0 @@
-<?php
-
-namespace DesignPatterns\Creational\Pool;
-
-class Processor
-{
-    private $pool;
-    private $processing = 0;
-    private $maxProcesses = 3;
-    private $waitingQueue = array();
-
-    public function __construct(Pool $pool)
-    {
-        $this->pool = $pool;
-    }
-
-    public function process($image)
-    {
-        if ($this->processing++ < $this->maxProcesses) {
-            $this->createWorker($image);
-        } else {
-            $this->pushToWaitingQueue($image);
-        }
-    }
-
-    private function createWorker($image)
-    {
-        $worker = $this->pool->get();
-        $worker->run($image, array($this, 'processDone'));
-    }
-
-    public function processDone($worker)
-    {
-        $this->processing--;
-        $this->pool->dispose($worker);
-
-        if (count($this->waitingQueue) > 0) {
-            $this->createWorker($this->popFromWaitingQueue());
-        }
-    }
-
-    private function pushToWaitingQueue($image)
-    {
-        $this->waitingQueue[] = $image;
-    }
-
-    private function popFromWaitingQueue()
-    {
-        return array_pop($this->waitingQueue);
-    }
-}

Creational/Pool/README.rst

@@ -33,21 +33,15 @@ Code
 
 You can also find these code on `GitHub`_
 
-Pool.php
+WorkerPool.php
 
-.. literalinclude:: Pool.php
+.. literalinclude:: WorkerPool.php
    :language: php
    :linenos:
 
-Processor.php
+StringReverseWorker.php
 
-.. literalinclude:: Processor.php
-   :language: php
-   :linenos:
-
-Worker.php
-
-.. literalinclude:: Worker.php
+.. literalinclude:: StringReverseWorker.php
    :language: php
    :linenos:
 
@@ -60,11 +54,5 @@ Tests/PoolTest.php
    :language: php
    :linenos:
 
-Tests/TestWorker.php
-
-.. literalinclude:: Tests/TestWorker.php
-   :language: php
-   :linenos:
-
 .. _`GitHub`: https://github.com/domnikl/DesignPatternsPHP/tree/master/Creational/Pool
 .. __: http://en.wikipedia.org/wiki/Object_pool_pattern

Creational/Pool/StringReverseWorker.php

@@ -2,18 +2,20 @@
 
 namespace DesignPatterns\Creational\Pool;
 
-class Worker
+class StringReverseWorker
 {
+    /**
+     * @var \DateTime
+     */
+    private $createdAt;
+
     public function __construct()
     {
-        // let's say that constuctor does really expensive work...
-        // for example creates "thread"
+        $this->createdAt = new \DateTime();
     }
 
-    public function run($image, array $callback)
+    public function run(string $text)
     {
-        // do something with $image...
-        // and when it's done, execute callback
-        call_user_func($callback, $this);
+        return strrev($text);
     }
 }

Creational/Pool/Tests/PoolTest.php

@@ -2,21 +2,28 @@
 
 namespace DesignPatterns\Creational\Pool\Tests;
 
-use DesignPatterns\Creational\Pool\Pool;
+use DesignPatterns\Creational\Pool\WorkerPool;
 
 class PoolTest extends \PHPUnit_Framework_TestCase
 {
-    public function testPool()
+    public function testCanGetNewInstancesWithGet()
     {
-        $pool = new Pool('DesignPatterns\Creational\Pool\Tests\TestWorker');
-        $worker = $pool->get();
+        $pool = new WorkerPool();
+        $worker1 = $pool->get();
+        $worker2 = $pool->get();
 
-        $this->assertEquals(1, $worker->id);
+        $this->assertCount(2, $pool);
+        $this->assertNotSame($worker1, $worker2);
+    }
 
-        $worker->id = 5;
-        $pool->dispose($worker);
+    public function testCanGetSameInstanceTwiceWhenDisposingItFirst()
+    {
+        $pool = new WorkerPool();
+        $worker1 = $pool->get();
+        $pool->dispose($worker1);
+        $worker2 = $pool->get();
 
-        $this->assertEquals(5, $pool->get()->id);
-        $this->assertEquals(1, $pool->get()->id);
+        $this->assertCount(1, $pool);
+        $this->assertSame($worker1, $worker2);
     }
 }

Creational/Pool/WorkerPool.php

@@ -2,29 +2,43 @@
 
 namespace DesignPatterns\Creational\Pool;
 
-class Pool
+class WorkerPool implements \Countable
 {
-    private $instances = [];
+    /**
+     * @var StringReverseWorker[]
+     */
+    private $occupiedWorkers = [];
 
+    /**
+     * @var StringReverseWorker[]
+     */
+    private $freeWorkers = [];
 
-    private $class;
-
-    public function __construct($class)
+    public function get(): StringReverseWorker
     {
-        $this->class = $class;
-    }
-
-    public function get()
-    {
-        if (count($this->instances) > 0) {
-            return array_pop($this->instances);
+        if (count($this->freeWorkers) == 0) {
+            $worker = new StringReverseWorker();
+        } else {
+            $worker = array_pop($this->freeWorkers);
         }
 
-        return new $this->class();
+        $this->occupiedWorkers[spl_object_hash($worker)] = $worker;
+
+        return $worker;
     }
 
-    public function dispose($instance)
+    public function dispose(StringReverseWorker $worker)
     {
-        $this->instances[] = $instance;
+        $key = spl_object_hash($worker);
+
+        if (isset($this->occupiedWorkers[$key])) {
+            unset($this->occupiedWorkers[$key]);
+            $this->freeWorkers[$key] = $worker;
+        }
+    }
+
+    public function count(): int
+    {
+        return count($this->occupiedWorkers) + count($this->freeWorkers);
     }
 }