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
