cookie

//servlet
//生成cookie对名象
java.util.Date date=new java.util.Date();
Cookie c=new Cookie("lastVisited",date.toString());
c.setMaxAge(60*60*24);//设置有效时间，单位秒
c.setPath("/");//设置路径
c.setDomain(".v512.com");//设置域名
//以上都有对应的get方法
response.addCookie(c);//保存对象到用户机硬盘上

//读取Cookie
Cookie[] cookies=request.getCookies();
Cookie c=null;
if(cookies!=null){
        for(int i=0;i<cookies.lenght;i++){
                c=cookies[i];
                out.println("cookie name:"+c.getName());
                out.println("cookie value:"+c.getValue());
        }
}

//修改Cookie
Cookie[] cookies=reuqest.getCookies();
Cookie c=null;
if(cookies!=null){
        for(int i=0;i<cookies.lenght;i++){
                c=cookies[i];
                if(c.getName().equals("lastVisited")){
                        c.setValue("2007-10-30");
                        c.setMaxAge(60*60*24);
                        response.addCookie(c);
                }
        }
}

//删除Cookie
Cookie[] cookies=reuqest.getCookies();
Cookie c=null;
if(cookies!=null){
        for(int i=0;i<cookies.lenght;i++){
                c=cookies[i];
                if(c.getName().equals("lastVisited")){
                        c.setMaxAge(0);
                        response.addCookie(c);
                }
        }
}