<?php

interface Storage
{
	public function set($data);
	public function get();
	public function store();
}


class MySQL implements Storage
{
	private $data;

	public function set($data){
		echo "MySQL Set";
		$this->data = $data;
	}

	public function get(){
		echo "MySQL Get";
		return $this->data;
	}

	public function store(){
		echo "MySQL Store";
	}
}

class ElasticSearch implements Storage
{
	private $data;

	public function set($data){
		echo "ElasticSearch Set";
		$this->data = $data;
	}

	public function get(){
		echo "ElasticSearch Get";
		return $this->data;
	}

	public function store(){
		echo "ElasticSearch Store";
	}
}

class Redis implements Storage
{
	private $data;

	public function set($data){
		echo "Redis Set";
		$this->data = $data;
	}

	public function get(){
		echo "Redis Get";
		return $this->data;
	}

	public function store(){
		echo "Redis Store";
	}
}

class Base
{
	private $storage_handler;

	public function __construct(Storage $storage_handler)
	{
		$this->storage_handler = $storage_handler;
	}

	public function test()
	{
		$this->storage_handler->set("Hello World");
		echo "<br/>";
		$this->storage_handler->get();
		echo "<br/>";
		$this->storage_handler->store();
	}
}

$base = new Base(new MySQL());
$base->test();
echo "<br/><br/>";
$base = new Base(new ElasticSearch());
$base->test();
echo "<br/><br/>";
$base = new Base(new Redis());
$base->test();