DbMgmt.php

<?php


namespace Db;

class DbMgmt
{
    const SERVERNAME = 'localhost';
    const PORT = "3306";
    const USERNAME = 'root';
    const PASSWORD = '';
    const DBNAME = 'universumphp';
    const CHARSET = 'utf8';
    public $conn;

    private static $instance = false;

    public function __constructor() {
        $this->newConn();
    }

    public  function newConn()
    {
        if (!self::$instance) {
            $sql = 'USE ' . self::DBNAME;
            try {
                $this->conn = new \PDO('mysql:host=' . self::SERVERNAME . ";port=" . self::PORT . ";charset=" . self::CHARSET, self::USERNAME, self::PASSWORD);
                $this->conn->setAttribute(\PDO::ATTR_ERRMODE, \PDO::ERRMODE_EXCEPTION);
                $this->conn->exec($sql);
                //  echo "Connection established <br>";
                self::$instance = true;

            } catch (\PDOException $e) {
                echo $sql . '<br>' . $e->getMessage();
            }
        } else {
            throw new \Exception('An instance of Connection is already present!');
        }

        return $this->conn;
    }
}