jsp request.getHeader的使用方法

最後更新：2017-01-13 來源：互聯網

上載者：User

創建阿里雲帳戶，並獲得超過 40 款產品的免費試用版；而企業帳戶則可以享有總值 $1200 的免費試用版。立即註冊！

連結過來的時候，referer的值是連結過來的頁面的URL，正常。我重新整理的時候referer的值沒有變，但當我在地址欄中打斷行符號（URL沒有改變，只是打斷行符號），referer值卻變成NULL了。

1）：連結過來和在地址欄中直接輸入URL，有沒有什麼區別？如果有，有什麼區別？
2）：重新整理的時候URL為什麼不變，為什麼還是前一個URL地址，為什麼不變成當前的URL？
3）：直接輸入為什麼得不到 <%=request.getHeader("REFERER")的值？

如果是直接在瀏覽器裡輸入有referer的頁面，返回是null，也就是說referer只有從別的頁面點擊串連來到這頁的才會有內容。為NULL就是手工，非null就是串連過來的。重新整理的時候，會檢查服務端是否會有更新，沒有的話，則使用原生緩衝，也就是說，你重新整理時得到的響應依然是

<%@ page import="java.util.*" %>
<html>
   <head>
      <title>Echo</title>
      <style>
      <jsp教程:include page="style.css教程" flush="true"/>
      </style>
   </head>
   <body>
      <h1>HTTP Request Headers Received</h1>
      <table border="1" cellpadding="4" cellspacing="0">
      <%
         Enumeration eNames = request.getHeaderNames();
         while (eNames.hasMoreElements()) {
            String name = (String) eNames.nextElement();
            String value = normalize(request.getHeader(name));
      %>
         <tr><td><%= name %></td><td><%= value %></td></tr>
      <%
         }
      %>
      </table>
   </body>
</html>
<%!
   private String normalize(String value)
   {
      StringBuffer sb = new StringBuffer();
      for (int i = 0; i < value.length(); i++) {
         char c = value.charAt(i);
         sb.append(c);
         if (c == ';')
            sb.append("<br>");
      }
      return sb.toString();
   }
%>

綜合執行個體

index.jsp

<HTML>
    <HEAD>
        <TITLE>Getting Header Data</TITLE>
    </HEAD>

    <BODY>
        <H1>Getting Header Data</H1>
        <FORM ACTION="basic.jsp" METHOD="POST">
            <INPUT TYPE="submit" VALUE="Submit">
        </FORM>
    </BODY>
</HTML>

basic.jsp

<HTML>
    <HEAD>
        <TITLE>Reading Header Information</TITLE>
    </HEAD>

    <BODY>
        <H1>Reading Header Information</H1>
        Here are the request headers and their data:
        <BR>
        <% java.util.Enumeration names = request.getHeaderNames();
        while(names.hasMoreElements()){
            String name = (String) names.nextElement();
            out.println(name + ":<BR>" + request.getHeader(name) + "<BR><BR>");
        }
        %>
    </BODY>
</HTML>

通過方法可以知道訪問者的request.getHeader("Referer");其他的方法下列
System.out.println("Protocol: " + request.getProtocol());
System.out.println("Scheme: " + request.getScheme());
System.out.println("Server Name: " + request.getServerName() );
System.out.println("Server Port: " + request.getServerPort());
System.out.println("Protocol: " + request.getProtocol());
System.out.println("Server Info: " + getServletConfig().getServletContext().getServerInfo());
System.out.println("Remote Addr: " + request.getRemoteAddr());
System.out.println("Remote Host: " + request.getRemoteHost());
System.out.println("Character Encoding: " + request.getCharacterEncoding());
System.out.println("Content Length: " + request.getContentLength());
System.out.println("Content Type: "+ request.getContentType());
System.out.println("Auth Type: " + request.getAuthType());
System.out.println("HTTP Method: " + request.getMethod());
System.out.println("Path Info: " + request.getPathInfo());
System.out.println("Path Trans: " + request.getPathTranslated());
System.out.println("Query String: " + request.getQueryString());
System.out.println("Remote User: " + request.getRemoteUser());
System.out.println("Session Id: " + request.getRequestedSessionId());
System.out.println("Request URI: " + request.getRequestURI());
System.out.println("Servlet Path: " + request.getServletPath());
System.out.println("Accept: " + request.getHeader("Accept"));
System.out.println("Host: " + request.getHeader("Host"));
System.out.println("Referer : " + request.getHeader("Referer"));
System.out.println("Accept-Language : " + request.getHeader("Accept-Language"));
System.out.println("Accept-Encoding : " + request.getHeader("Accept-Encoding"));
System.out.println("User-Agent : " + request.getHeader("User-Agent"));
System.out.println("Connection : " + request.getHeader("Connection"));
System.out.println("Cookie : " + request.getHeader("Cookie"));
System.out.println("Created : " + session.getCreationTime());
System.out.println("LastAccessed : " + session.getLastAccessedTime());

本文章原先以中文撰寫並發佈於 aliyun.com，亦設英文版本，僅作資訊用途。本網站不對文章的準確性，完整性或可靠性或其任何翻譯作出任何明示或暗示的陳述或保證。如對該文章有任何疑慮或投訴，請傳送電郵至 info-contact@alibabacloud.com 並提供相關疑慮或投訴的詳細說明。職員會於 5 個工作天內與您聯絡，一經驗證之後，即會刪除該侵權內容。

A Free Trial That Lets You Build Big!

Start building with 50+ products and up to 12 months usage for Elastic Compute Service

Get Started for Free

Sales Support

1 on 1 presale consultation

Chat Contact Sales
After-Sales Support

24/7 Technical Support 6 Free Tickets per Quarter Faster Response

Open a Ticket
Alibaba Cloud offers highly flexible support services tailored to meet your exact needs.

Learn More