jsp源码实例2（获取表单参数） package coreservlets;import java.io.*;import javax.servlet.*;import javax.servlet.http.*;import java.util.*;/** Shows all the parameters sent to the servlet via either* GET or POST. Specially marks parameters that have* no values or multiple values.*

* 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 ShowParameters extends HttpServlet {public void doGet(HttpServletRequest request,HttpServletResponse response)throws ServletException, IOException {response.setContentType("text/html");PrintWriter out = response.getWriter();String title = "Reading All Request Parameters";out.println(ServletUtilities.headWithTitle(title) +"\n" +"

" + title + "

\n" +"\n" +"\n" +"

Parameter Name	Parameter Value(s)");Enumeration paramNames = request.getParameterNames();while(paramNames.hasMoreElements()) {String paramName = (String)paramNames.nextElement();out.print("
" + paramName + "\n	");String[] paramValues =request.getParameterValues(paramName);if (paramValues.length == 1) {String paramValue = paramValues[0];if (paramValue.length() == 0)out.println("No Value");elseout.println(paramValue);} else {out.println(" ");for(int i=0; i" + paramValues);}out.println(" ");}}out.println("

\n");}public void doPost(HttpServletRequest request,HttpServletResponse response)throws ServletException, IOException {doGet(request, response);}}