예제 #1
0
 /**
  * 静态工厂方法,返还此类的唯一实例
  */
 public static function getInstance()
 {
     if (is_null(self::$_instance)) {
         self::$_instance = new ConcreteStateA();
     }
     return self::$_instance;
 }
예제 #2
0
 public static function getInstance()
 {
     // 静态工厂方法,返还此类的唯一实例
     if (is_null(self::$_instance)) {
         self::$_instance = new ConcreteStateA();
     }
     return self::$_instance;
 }