GoF Commandパターン

Command.php

<?php
    class File {
        private $name;
        
        public function __construct($name){
            $this->name = $name;
        }
        
        public function getName() {
            return $this->name;
        }
        
        public function decompress() {
            echo $this->name . "を展開しました<br>";
        }
        
        public function compress() {
            echo $this->name . "を圧縮しました<br>";
        }
        
        public function create() {
            echo $this->name . "を作成しました<br>";
        }
    }
    
    interface Command{
        public function execute();
    }
    
    class TouchCommand implements Command {
        private $file;
        public function __construct(File $file){
            $this->file = $file;
        }
        
        public function execute(){
            $this->file->create();
        }
    }
    
    class CompressCommand implements Command {
        private $file;
        public function __construct(File $file){
            $this->file = $file;
        }
        
        public function execute(){
            $this->file->compress();
        }
    }
    
    class CopyCommand implements Command {
        private $file;
        
        public function __construct(File $file){
            $this->file = $file;
        }
        
        public function execute(){
            $file = new File('copy_of_' . $this->file->getName());
            $file->create();
        }
    }
    
    class Queue {
        private $commands;
        private $current_index;
        
        public function __construct(){
            $this->commands = array();
            $this->current_index = 0;
        }
        
        public function addCommand(Command $command){
            $this->commands[] = $command;
        }
        
        public function run(){
            while (!is_null($command = $this->next())){
                $command->execute();
            }
        }
        
        public function next(){
            if (count($this->commands) === 0 ||
                count($this->commands) <= $this->current_index) {
                return null;
            }else{
                return $this->commands[$this->current_index++];
            }
        }
    }
    
    $queue = new Queue();
    $file  = new File("sample.txt");
    
    $queue->addCommand(new TouchCommand($file));
    $queue->addCommand(new CompressCommand($file));
    $queue->addCommand(new CopyCommand($file));
    
    $queue->run();