01_7_cookies

01_7_cookies

1. cookies

1.1服务器可以向客户端写内容

1.2只能是文本内容

1.3客户端可以阻止服务器写入

1.4只能拿到自己webapp写入的东西

1.5Cookie分为两种

属于窗口/子窗口(放在内存中)

属于文本(有生命周期的)

1.6一个servlet/jsp设置的cookies能够被同一个路径下面或者子路径下面的servlet/jsp读到(路径 = URL)(路径 != 真实文件路径)

2. 测试类

SetCookies.java

public void doGet(HttpServletRequest request, HttpServletResponse response)

throws ServletException, IOException {

 

/*response.setContentType("text/html");

PrintWriter out = response.getWriter();

out.println("<!DOCTYPE HTML PUBLIC \"-//W3C//DTD HTML 4.01 Transitional//EN\">");

out.println("<HTML>");

out.println("  <HEAD><TITLE>A Servlet</TITLE></HEAD>");

out.println("  <BODY>");

out.print("    This is ");

out.print(this.getClass());

out.println(", using the GET method");

out.println("  </BODY>");

out.println("</HTML>");

out.flush();

out.close();*/

for (int i = 0; i < 3; i++) {

Cookie cookie = new Cookie("Session-Cookie-" + i, "Cookie-Value-P" + i);

response.addCookie(cookie);

cookie = new Cookie("Persistent-Cookie-" + i, "Cookie-Value-P" + i);

cookie.setMaxAge(3600);

response.addCookie(cookie);

}

response.setContentType("text/html; charset=utf-8");

PrintWriter out = response.getWriter();

out.print("<H1>设置Cookie</H1>6个Cookie<a href=\"ShowCookies\">查看</a>");

}

 

ShowCookies.java

public void doGet(HttpServletRequest request, HttpServletResponse response)

throws ServletException, IOException {

 

response.setContentType("text/html; charset=utf-8");

PrintWriter out = response.getWriter();

String title = "Active Cookies";

out.println("<!DOCTYPE HTML PUBLIC \"-//W3C//DTD HTML 4.01 Transitional//EN\">");

out.println("<HTML>");

out.println("  <HEAD><TITLE>获取客户端Cookie</TITLE></HEAD>");

out.println("  <BODY>");

out.print("<H1 ALIGN=\"CENTER\">" + title +

"</H1><table  border=1 ALIGN=\"CENTER\">" +

"<tr><th>Cookie Name</th><th>Cookie Value</th>");

Cookie[] cookies = request.getCookies();

if (cookies != null) {

Cookie cookie;

for (int i = 0; i < cookies.length; i++) {

cookie = cookies[i];

out.print("<tr><td>" + cookie.getName()+"</td><td>" + cookie.getValue() + "</td></tr>");

}

}

out.print("</table>");

out.println("  </BODY>");

out.println("</HTML>");

out.flush();

out.close();

}

 

posted @ 2018-04-02 21:37  FlyBack  阅读(118)  评论(0)  编辑  收藏  举报