When the browser requests a web page, it sends a series of information to the network server that cannot be read directly because the information is transmitted as part of the HTTP header. You can check out the HTTP protocol for more information.
JSP client request syntax
After obtaining the Enumeration object, use the standard method to traverse the Enumeration object, use the hasMoreElements() method to determine when to stop, and use the nextElement() method to obtain the name of each parameter.
JSP client request example
<%@?page?language="java"?contentType="text/html;?charset=UTF-8"
????pageEncoding="UTF-8"%>
????<%@?page?import="java.io.*,java.util.*"?%>
????<!DOCTYPE?html>
????<html>
????<head>
????<meta?charset="utf-8">
????????<title>php.cn</title>
????</head>
????<body>
????<h2>HTTP?頭部請求實例</h2>
????<table?width="100%"?border="1"?align="center">
????<tr?bgcolor="#949494">
????<th>Header?Name</th>
????<th>Header?Value(s)</th>
????</tr>
????<%Enumeration?headerNames?=?request.getHeaderNames();
???while(headerNames.hasMoreElements())?{
??????String?paramName?=?(String)headerNames.nextElement();
??????out.print("<tr><td>"?+?paramName?+?"</td>\n");
??????String?paramValue?=?request.getHeader(paramName);
??????out.println("<td>?"?+?paramValue?+?"</td></tr>\n");}%>
???</table>
???</body>
???</html>