期末大作业基于java的校友管理系统源码.zip

package servlet; import util.DBUtil; 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; import java.io.IOException; import java.io.PrintWriter; import java.sql.Connection; import java.sql.PreparedStatement; import java.sql.ResultSet; /** * Servlet 注解配置信息 */ @WebServlet(name = "LoginServlet",value = "/login") public class LoginServlet extends HttpServlet { /** * post请求 会执行doPost方法 * @param request * @param response * @throws ServletException * @throws IOException */ protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { doGet(request,response); } /** * get请求 会执行doGet方法 * @param request * @param response * @throws ServletException * @throws IOException */ protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { System.out.println("servlet 请求"); request.setCharacterEncoding("utf-8"); String username = request.getParameter("username"); String password = request.getParameter("password"); HttpSession session = request.getSession(); if("1".equals(request.getParameter("invalidate")) && session.getAttribute("username") != null){ session.invalidate(); //session.removeAttribute("username"); response.sendRedirect("login.jsp"); } try { Connection connection = DBUtil.getConnection(); //sql 模板 String sql = "select * from user where username = ? and password = ?"; //使用PreparedStatement对象执行sql语句 PreparedStatement ps = connection.prepareStatement(sql); ps.setString(1,username); ps.setString(2,password); ResultSet rs = ps.executeQuery(); //response.setContentType("text/html;charset=UTF-8"); PrintWriter out = response.getWriter(); if(rs.next()){ //表示登录成功 session.setAttribute("username",username); response.sendRedirect("home.jsp"); }else{ //表示登录未成功 out.print("登录失败,3秒之后跳转登录页面..."); response.setHeader("refresh","3;url=login.jsp"); } //服务端跳转 //request.getRequestDispatcher("home.jsp").forward(request,response); DBUtil.close(connection,ps,rs); }catch (Exception e){ e.printStackTrace(); } } }