session实现购物系统的简例和application实现统计页面访问次数的简例

login.jsp

<body>
  <form action="checkLogin.jsp">
  <table>
  <tr><td>用户名：</td><td><input type="text" name="name"></td></tr>
  <tr><td>密&nbsp;&nbsp;码</td><td><input type="password" name="password"></td></tr>
  <tr><td colspan="2"><input type="submit" value="提交"></td></tr>
  </table>
  </form>
  </body>

checkLogin.jsp

<body>
  <%
  String name=(String)request.getParameter("name");
  String password=(String)request.getParameter("password");
 
  if(name.equals("admin")&&password.equals("admin")){
  session.setAttribute("name",name);
  session.setAttribute("password",password);
  response.sendRedirect("success.jsp");
  }else{
  response.sendRedirect("error.jsp");
  }
   %>
  </body>

success.jsp

<%
    String name=(String)session.getAttribute("name");
    String password=(String)session.getAttribute("password");
    out.println("用户名：");
    out.println(name);
    out.println("<br>");
    out.println("密码：");
    out.println(password);
   %>
   <a href="buygoods.jsp">购买商品</a>
  </body>

buygoods.jsp

<body>
  <%
  String name=(String)session.getAttribute("name");
  String password=(String)session.getAttribute("password");
 %>
  你好<%=name %>sessionId<%=session.getId() %>
  谢谢你购买本商品
 <a href="logout.jsp">注销</a>
  </body>

logout.jsp

<%
  session.invalidate();
  response.sendRedirect("login.jsp");
   %>

count.jsp

<body>
    <%
    if(application.getAttribute("count")==null){
    application.setAttribute("count",0);
    }
    Integer count=(Integer)application.getAttribute("count");
    application.setAttribute("count",(Integer)(count.intValue()+1));
     %>
     你好，你是第<%=count %>个访问本站的人
  </body>