编写html页面：
CheckUserServlet 信息：import java.io.IOException;import java.io.PrintWriter;import javax.servlet.ServletException;import javax.servlet.http.HttpServlet;import javax.servlet.http.HttpServletRequest;import javax.servlet.http.HttpServletResponse;public class CheckUserServlet extends HttpServlet { public void destroy() { super.destroy(); } public void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { doPost(request,response); } public void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { response.setContentType("text/html"); PrintWriter out = response.getWriter(); //这里假设已经注册过了四位用户 String[] logined = {"admin","users","zhangsan","lisi"}; //接收从客户端提交的loginName参数 String loginName = request.getParameter("loginName"); //创建一个存放响应内容的字符串 String responseContext = "true"; for (int i=0;i
CreateXMLServlet 信息：import java.io.IOException;import java.io.PrintWriter;import javax.servlet.ServletException;import javax.servlet.http.HttpServlet;import javax.servlet.http.HttpServletRequest;import javax.servlet.http.HttpServletResponse;public class CreateXMLServlet extends HttpServlet { public CreateXML() { super(); } public void destroy() { super.destroy(); } public void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { doPost(request,response); } public void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { response.setContentType("text/xml"); response.setCharacterEncoding("UTF-8"); String selected = request.getParameter("selected"); PrintWriter out = response.getWriter(); out.println("