validação e-mail FILTER_VALIDATE_EMAIL

<?php
class Cliente{
    public $nome;
    protected $email;

    public function getEmail(){
        return $this->email;
    }
    public function setEmail($email){
        if(filter_var(FILTER_VALIDATE_EMAIL))
        $this->email=$email;
        return true;
    }
    exit('Email invalido');
}