<pre style="word-wrap: break-word; white-space: pre-wrap;">&lt;?php

/**
 * interface for creating render classes
 */
interface RenderTemplateInterface 
{
    public function renderHeader();
    public function renderBody();
    public function renderFooter();
}
 
/**
 * Used for rendering HTML templates
 */
class RenderHTMLTemplate implements RenderTemplateInterface 
{
 
    public function renderHeader() 
    {
        return "&lt;html&gt;&lt;body&gt;";
    }
 
    public function renderBody() 
    {
        return "Hello World";
    }
 
    public function renderFooter() 
    {
        return "&lt;/body&gt;&lt;/html&gt;";
    }
 
}
 
/**
 * Separate interface just for rendering PDF's
 * Having a separate interface from RenderTemplateInterface could be a requirement from a third party
 */
interface PDFTemplateInterface 
{
    public function renderTop();
    public function renderMiddle();
    public function renderBottom();
}
 
/**
 * Used for rendering PDF templates
 */
class RenderPDFTemplate implements PDFTemplateInterface 
{
 
    public function renderTop() 
    {
        return "This is the top of the PDF";
    }
 
    public function renderMiddle() 
    {
        return "Hello World";
    }
 
    public function renderBottom() 
    {
        return "This is the bottom of the PDF";
    }
 
}
 
/**
 * The adapter - this will encapsulate an instance of the RenderPDFTemplate class
 * to work polymorphically with the RenderTemplateInterface interface
 */
class PDFTemplateAdapter implements RenderTemplateInterface
{
    private $pdfTemplate;
 
    public function __construct(PDFTemplateInterface $pdfTemplate)
    {
        $this-&gt;pdfTemplate = $pdfTemplate;
    }
 
    public function renderHeader() 
    {
        return $this-&gt;pdfTemplate-&gt;renderTop();
    }
 
    public function renderBody() 
    {
        return $this-&gt;pdfTemplate-&gt;renderMiddle();
    }
 
    public function renderFooter() 
    {
        return $this-&gt;pdfTemplate-&gt;renderBottom();
    }
}
 
$pdfTemplate = new RenderPDFTemplate();
 
// $pdfTemplateAdapter will implement RenderTemplateInterface, just like RenderHTMLTemplate does
$pdfTemplateAdapter = new PDFTemplateAdapter($pdfTemplate);
 
// This is the top of the PDF
echo $pdfTemplateAdapter-&gt;renderHeader();
</pre>