如何建一个网站,东莞有哪些公司,文案类的网站,上海有制作网站的电话吗1.Session的概念
Session是依赖于Cookie的#xff0c;每次请求时#xff0c;会将特殊标识带到服务器端#xff0c;根据这个标识来找到对应的内存空间#xff0c;从而实现数据共享!是Servlet规范中四大域对象之一的会话域对象。作用:是Servlet规范中四大域对象之一的会话域…1.Session的概念
Session是依赖于Cookie的每次请求时会将特殊标识带到服务器端根据这个标识来找到对应的内存空间从而实现数据共享!是Servlet规范中四大域对象之一的会话域对象。作用:是Servlet规范中四大域对象之一的会话域对象。可以实现数据共享
2.Session设置共享数据
//Session的基本使用
WebServlet(/ServletDemo1)
public class ServletDemo1 extends HttpServlet {Overrideprotected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {//设置请求字符编码,防止乱码req.setCharacterEncoding(utf-8);//设置浏览器响应编码[html类型的文本,字符集为utf-8]resp.setContentType(text/html;charsetutf-8);//1.获取请求的用户名String username req.getParameter(username);//2.获取HttpSession的对象HttpSession session req.getSession(true);//默认为true,表示没有session则自动创建//[验证是否为同一Session]System.out.println(session);System.out.println(session.getId());//3.将用户名信息添加到共享数据中session.setAttribute(username,username);//2.解决Cookie禁用方法2重写urla hrefresp.encodeURL(http://localhost:8080/Session/ServletDemo3)go servletDemo1/a// resp.getWriter().write(a hrefresp.encodeURL(http://localhost:8080/Session/ServletDemo3)go servletDemoO/a);}Overrideprotected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {doGet(req, resp);}
}
3.Session获取共享数据
//Session获取共享数据[同一个session]
WebServlet(/ServletDemo2)
public class ServletDemo2 extends HttpServlet {Overrideprotected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {//设置浏览器响应编码[html类型的文本,字符集为utf-8]resp.setContentType(text/html;charsetutf-8);//1.获取HttpSession对象HttpSession session req.getSession();//[验证是否为同一Session]System.out.println(session);System.out.println(session.getId());//2.获取共享数据String username (String) session.getAttribute(username);//3.将响应数据给浏览器resp.getWriter().write(username);}Overrideprotected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {doGet(req, resp);}
}
4.Cookie的禁用解决方法
//Cookie的禁用
WebServlet(/ServletDemo3)
public class ServletDemo3 extends HttpServlet {Overrideprotected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {//1.解决方法1提示HttpSession session req.getSession(false);System.out.println(session);if (sessionnull){resp.setContentType(text/html;charsetutf-8);resp.getWriter().write(为了不影响使用请不要禁用浏览器的Cookie);}//2.解决方法2重写urla 【需到第一个界面重写】hrefresp.encodeURL(http://localhost:8080/Session/ServletDemo3)go servletDemo1/a// resp.getWriter().write(a hrefresp.encodeURL(http://localhost:8080/Session/ServletDemo3)go servletDemoO/a);}Overrideprotected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {doGet(req, resp);}
}
