使用cookie完成用户自动登录

Login.jsp

<form action="back.jsp" method="post">

  name:<input type="text" name="name"/>

   <input type="submit" value="submit"/>

</form>

Back.jsp

<%

  String name = request.getParameter("name");

  if(name !=null && !name.trim().equals("")){

  Cookie cookie =new Cookie("name",name);

  cookie.setMaxAge(15);

  response.addCookie(cookie);

  }

  else{

  Cookie [] cookies = request.getCookies();

  if(cookies !=null && cookies.length>0){

  for(Cookie cookie:cookies){

  String name1 = cookie.getName();

  if(name1.equals("name")){

  String val = cookie.getValue();

  name = val;

  }

  }

  }

  }

  if(name !=null && !name.trim().equals("")){

  out.print("Hello"+ name);

  }

else{

response.sendRedirect("login.jsp");

}

%>