浅谈PHP设计模式之门面模式Facade

<?php

namespace DesignPatterns\Structural\Facade;

class Facade
{
    
    private $os;

    
    private $biOS;

    
    public function __construct(BiosInterface $bios, OsInterface $os)
    {
        $this->bios = $bios;
        $this->os = $os;
    }

    
    public function turnOn()
    {
        $this->bios->execute();
        $this->bios->waitForKeyPress();
        $this->bios->launch($this->os);
    }

    
    public function turnOff()
    {
        $this->os->halt();
        $this->bios->powerDown();
    }
}

<?php

namespace DesignPatterns\Structural\Facade;


interface OsInterface
{
    
    public function halt();

    
    public function getName(): string;
}

<?php

namespace DesignPatterns\Structural\Facade;


interface  BiosInterface
{
    
    public function execute();

    
    public function waitForKeyPress();

    
    public function launch(OsInterface $os);

    
    public function powerDown();
}

<?php

namespace DesignPatterns\Structural\Facade\Tests;

use DesignPatterns\Structural\Facade\Facade;
use DesignPatterns\Structural\Facade\OsInterface;
use PHPUnit\Framework\TestCase;


class FacadeTest extends TestCase
{
    public function testComputerOn()
    {
        
        $os = $this->createMock('DesignPatterns\Structural\Facade\OsInterface');

        $os->method('getName')
            ->will($this->returnValue('linux'));

        $bios = $this->getMockBuilder('DesignPatterns\Structural\Facade\BiosInterface')
            ->setMethods(['launch', 'execute', 'waitForKeyPress'])
            ->disableAutoload()
            ->getMock();

        $bios->expects($this->once())
            ->method('launch')
            ->with($os);

        $facade = new Facade($bios, $os);

        // 门面接口很简单。
        $facade->turnOn();

        // 但你也可以访问底层组件。
        $this->assertEquals('Linux', $os->getName());
    }
}