Proxy

Intent

Provide a surrogate or placeholder for another object to control access to it

Motivation

We want to provide a wrapper around a set of classes to unify their access protocols

Implementation

• Provide a wrap method
• intercept calls to the wraper object and forward them accordingly, may change the protocol

Example

class Fluenter
{
        private $obj;

        function __construct($obj)
        {
                $this->obj = $obj;
        }
        static function MakeFluent($obj)
        {
                if ($obj instanceof fluent)
                        return $obj;
                else
                        return new fluenter($obj);
        }
        function __call($method, $args)
        {
                $result = call_user_func_array(array($this->obj, $method), $args);
                if (is_null($result))
                        return $this;
                else if (is_object($result) and ($result instanceof $fluent))
                        return $result;
                else
                        throw new RuntimeException(
                                                "Fluent::__call called method $method ".
                                                "and expected a null return or a non-fluent object, ".
                                                "got (".gettype($return).") $return instead.");
        }
}

notes

• This code is an unaltered copy from Making Fluent Interfaces Readable in PHP, I hope Jonnay doesn't mind that
• You might want to check out fluent interfaces( method chaining) and accumulator passing