下图是大概的显示效果图
以下是该界面的代码
package cn.edu.mju.project2.controller;import javax.servlet.Servlet;import javax.servlet.ServletContext;import javax.servlet.ServletException;import javax.servlet.annotation.WebServlet;import javax.servlet.http.HttpServlet;import javax.servlet.http.HttpServletRequest;import javax.servlet.http.HttpServletResponse;import java.io.IOException;import java.io.PrintWriter;@WebServlet("/login")public class LoginController extends HttpServlet {@Overrideprotected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {StringBuilder stringBuilder=new StringBuilder();stringBuilder.append("<font size='20' >欢迎登录世外桃源</font>");//标题名字stringBuilder.append("<form action='' method='post'>");//输出本地stringBuilder.append("登陆名称：<input type='text' name='loginName' value=''/><br> ");//登录账号stringBuilder.append("登陆密码：<input type='password' name='loginPwd' value=''/> <br>");//登录密码stringBuilder.append("验 证 码：<input type='text' name='validCode'/><br><img src='./captcha' width=150 height=150 /> <br>");//输入验证码stringBuilder.append("<input type ='submit' name='btnLogin' value='登录'/>");//登录按钮stringBuilder.append("</form>");showMsg(resp,stringBuilder.toString());}@Overrideprotected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {String loginName=req.getParameter("loginName");String loginPwd=req.getParameter("loginPwd");String validCode = req.getParameter("validCode");ServletContext application = this.getServletContext();application.setAttribute("c",1);String saveCode = (String) req.getSession().getAttribute("code");//登陆名称是你的学号，密码是1234，否则，显示账户或密码错误String msg=null;if(saveCode !=null){if (saveCode.equals(validCode)){if("5197101241".equals(loginName)&&"123456".equals(loginPwd)){msg=("<font size='20' > 你好 "+loginName+"</font>");}else{msg=("<font size='20' >账户或密码错误</font>");}}else {msg = "验证码错误";}}else {msg = ("<font size='20' >请输入验证码</font>");}showMsg(resp,msg);}/*把要显示的内容输出到客户端*/private void showMsg(HttpServletResponse resp,String msg){resp.setCharacterEncoding("utf-8");try {PrintWriter out = resp.getWriter();out.println("<html>");out.println("<header>");out.println("<title>test</title>");out.println("<meta charset=\"utf-8\">");out.println("</header>");out.println("<body>"+"<center>");out.println(msg);out.println("</body>"+"</center>");out.println("</html>");out.close();}catch (Exception e){System.out.println(e.getMessage());}}}
以上有涉及到验证码功能，读者可以观看另片关于验证码的文章
以上内容是个人的一点总结，如果有错误或不严谨的地方，望能批评指正，欢迎点赞收藏。
