servlet主要用负责web程序中的逻辑处理,属于MVC三层结构中的C(control)层,一般来讲一次请求会对应有一个servlet类,eclipse中可以直接创建servlet类
1.新建servlet
2.填写Class名:
3.设定访问路径
4.点击完成后生成如下代码:
@WebServlet("/Upload") public class Upload extends HttpServlet { private static final long serialVersionUID = 1L; /** * @see HttpServlet#HttpServlet() */ public Upload() { super(); // TODO Auto-generated constructor stub } /** * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response) */ protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { // TODO Auto-generated method stub response.getWriter().append("Served at: ").append(request.getContextPath()); } /** * @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response) */ protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { // TODO Auto-generated method stub doGet(request, response); } }
然后在doGet()方法中编写代码。
5.session和application用如下代码获得:
ServletContext application = this.getServletContext(); HttpSession session = request.getSession();