jsp源码实例3(获取jsp各种参数)

  package coreservlets;

  import java.io.*;

  import javax.servlet.*;

  import javax.servlet.http.*;

  import java.util.*;

  /** Creates a table showing the current value of each

  * of the standard CGI variables.

  * <P>

  * Taken from Core Servlets and JavaServer Pages

  * from Prentice Hall and Sun Microsystems Press,

  * http://www.coreservlets.com/.

  * © 2000 Marty Hall; may be freely used or adapted.

  */

  public class ShowCGIVariables extends HttpServlet {

  public void doGet(HttpServletRequest request,

  HttpServletResponse response)

  throws ServletException, IOException {

  response.setContentType("text/html");

  PrintWriter out = response.getWriter();

  String[][] variables =

  { { "AUTH_TYPE", request.getAuthType() },

  { "CONTENT_LENGTH",

  String.valueOf(request.getContentLength()) },

  { "CONTENT_TYPE", request.getContentType() },

  { "DOCUMENT_ROOT",

  getServletContext().getRealPath("/") },

  { "PATH_INFO", request.getPathInfo() },

  { "PATH_TRANSLATED", request.getPathTranslated() },

  { "QUERY_STRING", request.getQueryString() },

  { "REMOTE_ADDR", request.getRemoteAddr() },

  { "REMOTE_HOST", request.getRemoteHost() },

  { "REMOTE_USER", request.getRemoteUser() },

  { "REQUEST_METHOD", request.getMethod() },

  { "SCRIPT_NAME", request.getServletPath() },

  { "SERVER_NAME", request.getServerName() },

  { "SERVER_PORT",

  String.valueOf(request.getServerPort()) },

  { "SERVER_PROTOCOL", request.getProtocol() },

  { "SERVER_SOFTWARE",

  getServletContext().getServerInfo() }

  };

  String title = "Servlet Example: Showing CGI Variables";

  out.println(ServletUtilities.headWithTitle(title) +

  "<BODY BGCOLOR=\"#FDF5E6\">\n" +

  "<H1 ALIGN=\"CENTER\">" + title + "</H1>\n" +

  "<TABLE BORDER=1 ALIGN=\"CENTER\">\n" +

  "<TR BGCOLOR=\"#FFAD00\">\n" +

  "<TH>CGI Variable Name<TH>Value");

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

  String varName = variables[0];

  String varValue = variables[i][1];

  if (varValue == null)

  varValue = "<I>Not specified</I>";

  out.println("<TR><TD>" + varName + "<TD>" + varValue);

  }

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

  }

  /** POST and GET requests handled identically. */

  public void doPost(HttpServletRequest request,

  HttpServletResponse response)

  throws ServletException, IOException {

  doGet(request, response);

  }

  }