数据库连接构造函数:私有或公共

如果我想创建一个连接类，是否可以将__construct作为私有?或者，如果同时有多个用户，将阻止用户连接?或者我做了一些完全错误的事情，这个连接类甚至不应该存在?(使用没有特定类的连接会更好吗?)

   <?php
class Connection
{     
    private $host = "hostname";
    private $db_name = "somedatabase";
    private $username = "username";
    private $password = "";
    private $conn;
    private function __construct()
 {

        try {
        $this->conn = new PDO("mysql:host=" . $this->host . ";dbname=" . $this->db_name, $this->username, $this->password);
            $this->conn->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION); 
            echo "Connected Successfully Bro";
        }
  catch(PDOException $exception) 
  {
            echo "Connection error: " . $exception->getMessage();
        }
        return $this->conn;
    }
}

?>