Servlet体系结构
GenericServlet类：将Servlet类当中除了service方法之外的其他方法做了空实现，只有service作为抽象方法 HttpServlet类（对HTTP协议的封装和学习）（推荐使用！）： 实现请求方式“Get”和“Post”的判断：doGet()和doPost()方法 对HTTP协议的一种封装，简化操作 HttpServlet的使用方法： @Override protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException { System.out.println("doGet..."); } @Override protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException { System.out.println("doPost..."); } <!--login.html--> <body> <form action = "/day_servlet/demo" method = "post"> <input name = "username"> <input