web后端开发-实现web端线上答题程序

import java.io.IOException; 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 javax.servlet.http.HttpSession; // 线上答题 //每人最多答题5次，5次后不能提交 /** * Servlet implementation class TestServlet */ @WebServlet("/testservlet") public class TestServlet extends HttpServlet { private static final long serialVersionUID = 1L; /** * @see HttpServlet#HttpServlet() */ public TestServlet() { super(); // TODO Auto-generated constructor stub } /** * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response) */ protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { // TODO Auto-generated method stub response.getWriter().append("Served at: ").append(request.getContextPath()); } /** * @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response) */ protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { HttpSession session = request.getSession(); // 获取当前会话 Integer attemptCount = (Integer) session.getAttribute("attemptCount"); // 获取已尝试次数 if(attemptCount == null) { attemptCount = 0; // 第一次尝试 } else if(attemptCount >= 5) { // 如果尝试次数超过5次，重定向到一个提示页面或者在当前页面显示提示信息 response.sendRedirect("maxAttempts.jsp"); // 假设有一个maxAttempts.jsp页面用来提示用户已达到最大尝试次数 return; // 结束方法执行 } // 记录本次尝试 attemptCount++; session.setAttribute("attemptCount", attemptCount); //获取前端输入 String answer1 = request.getParameter("first"); String answer2 = request.getParameter("second"); String answer3 = request.getParameter("third"); // 正确或错误的标识row,1正确，错误 int row1 = -1;// 赋初始值，-1非法 int row2 = -1; int row3 = -1; // 第一题答案Java if("Java".equals(answer1)){ row1 = 1; } else{ row1 = 0; } // 第二题答案Eclipse if("Eclipse".equals(answer2)){ row2 = 1; } else{ row2 = 0; } // 第三题答案Apache Tomcat if("Apache Tomcat".equals(answer3)){ row3 = 1; } else{ row3 = 0; } request.setCharacterEncoding("UTF-8"); // 将答案和答案的正误标识存储在请求对象中 request.setAttribute("answer1", answer1); request.setAttribute("answer2", answer2); request.setAttribute("answer3", answer3); request.setAttribute("row1", row1); request.setAttribute("row2", row2); request.setAttribute("row3", row3); // 转发到的JSP页面中访问，用于展示用户的答案和判定结果 request.getRequestDispatcher("index.jsp").forward(request,response); } }