php design mode Command of command mode

< ?php
/**
* command mode
*
* encapsulating one request into one object allows you to parameterize customers with different requests, exclude or log requests, and support cancelable operations
*/
interface Command
{
public function execute();
}

class Invoker
{
private $_command = array();
public function setCommand($command) {
$this- > _command[] = $command;
}

public function executeCommand()
{
foreach($this- > _command as $command)
{
$command- > execute();
}
}

public function removeCommand($command)
{
$key = array_search($command, $this- > _command);
if($key !== false)
{
unset($this- > _command[$key]);
}
}
}

class Receiver
{
private $_name = null;

public function __construct($name) {
$this- > _name = $name;
}

public function action()
{
echo $this- > _name." action < br/ > ";
}

public function action1()
{
echo $this- > _name." action1 < br/ > ";
}
}

class ConcreteCommand implements Command
{
private $_receiver;
public function __construct($receiver)
{
$this- > _receiver = $receiver;
}

public function execute()
{
$this- > _receiver- > action();
}
}

class ConcreteCommand1 implements Command
{
private $_receiver;
public function __construct($receiver)
{
$this- > _receiver = $receiver;
}

public function execute()
{
$this- > _receiver- > action1();
}
}

class ConcreteCommand2 implements Command
{
private $_receiver;
public function __construct($receiver)
{
$this- > _receiver = $receiver;
}

public function execute()
{
$this- > _receiver- > action();
$this- > _receiver- > action1();
}
}


$objRecevier = new Receiver("No.1");
$objRecevier1 = new Receiver("No.2");
$objRecevier2 = new Receiver("No.3");

$objCommand = new ConcreteCommand($objRecevier);
$objCommand1 = new ConcreteCommand1($objRecevier);
$objCommand2 = new ConcreteCommand($objRecevier1);
$objCommand3 = new ConcreteCommand1($objRecevier1);
$objCommand4 = new ConcreteCommand2 ($objRecevier2); // two methods using Recevier

$objInvoker = new Invoker();
$objInvoker- > setCommand($objCommand);
$objInvoker- > setCommand($objCommand1);
$objInvoker- > executeCommand();
$objInvoker- > removeCommand($objCommand1);
$objInvoker- > executeCommand();

$objInvoker- > setCommand($objCommand2);
$objInvoker- > setCommand($objCommand3);
$objInvoker- > setCommand($objCommand4);
$objInvoker- > executeCommand();
[/code]