Just a simple experiment on AOP in PHP.

index.php

<?php

require 'movement.php';
require 'register_aop.php';

try {
    $movement = new Movement;
    $movement->walk();
    $movement->run();

    $movement->crawl(50);

    $movement->training();
    $movement->training();
    $movement->training();
    $movement->training();
    $movement->training();
    $movement->training();
    $movement->training();
    $movement->training();
    $movement->training();
    $movement->training();
    $movement->training();

    $movement->secretFly();
} catch (Exception $e) {
    print $e->getMessage();
}

movement.php

<?php

class Movement
{
    protected $power = 10;

    public function run($speed = 20)
    {
        echo "i can run at $speed Km/h";
    }

    public function walk($speed = 10)
    {
        echo "i can walk at $speed Km/h";
    }

    public function stop()
    {
        echo "i can stop.....";
    }

    public function crawl($speed = 5)
    {
        echo "i can crawl at $speed Km/h";
    }

    public function secretFly()
    {
        echo "how can you see me fly?";
    }

    public function training()
    {
        // Ini aneh, bila menggunakan metode
        //      $this->power += 10;
        // maka aop tidak dijalankan
        $newPower = $this->power + 10;
        $this->power = $newPower;

        return $this->power;
    }

    public function setPower($value = 10)
    {
        $this->power = $value;
        echo "My power is now " . $this->power . "\n";
    }
}

register_aop.php

<?php

function dontMove()
{
    throw new Exception("This movement is not allowed for you to see\n");
}

function gossip(AopJoinPoint $obj)
{
    $activity = $obj->getMethodName();

    if (substr($activity, -3, strlen($activity)) == 'ing') {
        echo "Wow, he is $activity\n";
    } else {
        echo "Wow, he can $activity\n";
    }
}

function lookMa()
{
    echo "Look ma, ";
}

function giveMeABreak()
{
    echo "\n";
}

// Memotong alur eksekusi sebuah fungsi
aop_add_before('Movement->secretFly()', 'dontMove');

aop_add_before('Movement->*()', 'gossip');
aop_add_before('Movement->*()', 'lookMa');
aop_add_after('Movement->*()', 'giveMeABreak');

// Mencoba closure -- Ini mengubah argumen yang diberikan kepada
// metode crawl
aop_add_before('Movement->crawl()', function(AopJoinPoint $obj){
    $args = $obj->getArguments();

    if ($args[0] >= 20) {
        echo "You can't crawl at {$args[0]} Km/h. You lied\n";
        $obj->setArguments(array(15));
    }
});

// Mendeteksi ketika terjadi perubahan pada properti yang dipantau
aop_add_before('write Movement->power', function(AopJoinPoint $obj){
    echo $obj->getPropertyName() . ' = ' . $obj->getAssignedValue() . "\n";
});

// Mendeteksi bila kembalian suatu fungsi berada di luar spesifikasi
aop_add_after('Movement->training()', function(AopJoinPoint $obj){
    if ($obj->getReturnedValue() > 100) {
        echo "You're pushing yourself. Go get some rest\n";

        $m = $obj->getObject();
        $m->setPower(10);
    }
});