Simple text formatter with name parameter

gistfile1.txt

<?php

class TextBuilder {
    private $template;
    private $parameters;
    
    public function __construct($template = null, array $parameters = null) {
        $this->template = $template;
        $this->parameters = $parameters ? $parameters : array();
    }
    
    public function setParameter($name, $value) {
        $this->parameters[$name] = $value;
    }
    
    public function getParameter($name) {
        if(array_key_exists($name, $this->parameters)) {
            return $this->parameters[$name];
        }
        else {
            return null;
        }
        
    }
    
    public function getParameters() {
        return $this->parameters;
    }
    
    public function setTemplate($template) {
        $this->template = $template;
    }
    
    public function getTemplate() {
        return $this->template;
    }
    
    public function render() {
        if(is_null($this->template)) {
            throw new \RuntimeException("Define a template first");
        }
        
        return str_replace(array_keys($this->parameters), $this->parameters, $this->template);
    }
}

$textRender = new TextBuilder("Hello :name. How are you ? :name I need to talk to you");
$textRender->setParameter(":name", "john");
echo $textRender->render(); // Hello john

echo "\n";

$textRender = new TextBuilder();
$textRender->setTemplate("Hello :name. How are you ?");
$textRender->setParameter(":name", "john doe");
echo $textRender->render(); // Hello john

echo "\n";

?>