implement copying of Stations for Seminary copy feature

drivers/DatabaseDriver.inc

@@ -0,0 +1,87 @@
+<?php
+
+    /**
+     * NRE
+     *
+     * @author      coderkun <olli@coderkun.de>
+     * @copyright   2013 coderkun (http://www.coderkun.de)
+     * @license     http://www.gnu.org/licenses/gpl.html
+     * @link        http://www.coderkun.de/projects/nre
+     */
+
+    namespace nre\drivers;
+
+
+    /**
+     * Abstract class for implementing a database driver.
+     * 
+     * @author  coderkun <olli@coderkun.de>
+     */
+    abstract class DatabaseDriver extends \nre\core\Driver
+    {
+        /**
+         * Driver class instance
+         * 
+         * @static
+         * @var DatabaseDriver
+         */
+        protected static $driver = null;
+        /**
+         * Connection resource
+         * 
+         * @var resource
+         */
+        protected $connection = null;
+
+
+
+
+        /**
+         * Singleton-pattern.
+         * 
+         * @param   array           $config Database driver configuration
+         * @return  DatabaseDriver          Singleton-instance of database driver class
+         */
+        public static function singleton($config)
+        {
+            // Singleton
+            if(self::$driver !== null) {
+                return self::$driver;
+            }
+
+            // Construct
+            $className = get_called_class();
+            self::$driver = new $className($config);
+
+
+            return self::$driver;
+        }
+
+
+        /**
+         * Construct a new database driver.
+         * 
+         * @param   array   $config Connection and login settings
+         */
+        protected function __construct($config)
+        {
+            parent::__construct();
+
+            // Establish connection
+            $this->connect($config);
+        }
+
+
+
+
+        /**
+         * Establish a connect to a MqSQL-database.
+         * 
+         * @throws  \nre\exceptions\DatamodelException
+         * @param   array   $config Connection and login settings
+         */
+        protected abstract function connect($config);
+
+    }
+
+?>