Servlet中的静态变量

Question

我对Servlets很新。我无法弄清楚以下代码的行为。

public class HelloServlet extends HttpServlet {

  static int counter = 0;

  public void doGet(HttpServletRequest req, HttpServletResponse res)
          throws IOException {
      if (counter == 0) {
          httpServletResponse.getWriter().print("Counter = " + counter);
          counter++;
      } else {
          httpServletResponse.getWriter().print("Counter = " + counter);
      }
   }
}

当我部署并运行它时，结果为＆＃34; Counter = 1＆＃34;在浏览器中。为什么跳过＆＃34; Counter = 0＆＃34;直接打印＆＃34; Counter = 1＆＃34;？