?php
/**
 * 对象工厂
 * @author flynetcn
 */
class ObjectFactory
{
  private static $objSet = array();
  /**
   * 清空工厂中的对象
   */
  public function clear()
  {
    self::$objSet = array();
  }
  /**
   * 在工厂中创建对象并将其返回
   * 参数格式：$class_name, $class_param1, $class_param2, ...
   */
  public static function create()
  {
    $argc = func_num_args();
    if ($argc = 0) {
      throw new Exception('params error', 1);
    }
    $args = func_get_args();
    $class_name = array_shift($args);
    $params = $args;
    if (!$params) {
      $class_sign = $class_name;
    } else {
      $param_sign = serialize($params);
      if (strlen($param_sign) > 100) {
        $param_sign = md5($param_sign);
      }
      $class_sign = $class_name.'@'.$param_sign;
    }
    if (isset(self::$objSet[$class_sign])) {
      return self::$objSet[$class_sign];
    }
    $ref = new ReflectionClass($class_name);
    if ($ref->hasMethod('__construct')  !empty($params)) {
      $obj = $ref->newInstanceArgs($params);
    } else {
      $obj = $ref->newInstance();
    }
    self::$objSet[$class_sign] = $obj;
    return $obj;
  }
}