1: <?php
 2: namespace Module\DB;
 3: 
 4: /**
 5:  * Implements a singleton database class
 6:  *
 7:  * This abstract class is to ensure that only one PDO instance is used. You get
 8:  * a instance of the database with:
 9:  *
10:  * ### Usage
11:  *
12:  * <code>
13:  *   \Module\DB\DB::$dbhost = 'localhost';
14:  *   \Module\DB\DB::$dbname = 'db';
15:  *   \Module\DB\DB::$dbuser = 'username';
16:  *   \Module\DB\DB::$dbpass = 'itsmeopenup';
17:  *   $db = \Module\DB\DB::getInstance();
18:  * </code>
19:  *
20:  * ### Changelog
21:  *
22:  * ## Version 1.12
23:  * * Added the date section to the documentation
24:  *
25:  * @date August 13, 2014
26:  * @author Jaime A. Rodriguez <hi.i.am.jaime@gmail.com>
27:  * @version 1.2
28:  * @license  http://opensource.org/licenses/MIT
29:  */
30: abstract class DB {
31: 
32:     /**
33:      * PDO The single instance is stored here.
34:      * @private
35:      */
36:     private static $instance = NULL;
37: 
38:     /**
39:      * string The database host
40:      */
41:     public static $dbhost = DBHOST;
42: 
43:     /**
44:      * string The database name
45:      */
46:     public static $dbname = DBNAME;
47: 
48:     /**
49:      * string The database user
50:      */
51:     public static $dbuser = DBUSER;
52: 
53:     /**
54:      * string The database password
55:      */
56:     public static $dbpass = DBPASS;
57: 
58:     /**
59:     * Sets constructor to private, prevents new instances
60:     */
61:     private function __construct() {}
62: 
63:     /**
64:     * Sets __clone to private, prevents clones
65:     */
66:     private function __clone(){}
67: 
68:     /**
69:     * Gets the DB instance or creates an initial connection
70:     *
71:     * @return object (PDO)
72:     */
73:     public static function getInstance() {
74:         if (!self::$instance) {
75:             self::$instance = new \PDO("mysql:host=" . self::$dbhost . ";dbname=" . self::$dbname, self::$dbuser, self::$dbpass);
76:             self::$instance-> setAttribute(\PDO::ATTR_ERRMODE, \PDO::ERRMODE_EXCEPTION);
77:         }
78:         return self::$instance;
79:     }
80: }
81: 
82: