JavaWeb学生信息管理平台开发实战：Servlet+JSP+MySQL技术栈
本文介绍一套基于经典JavaWeb技术栈构建的学生信息管理平台，采用分层架构设计，涵盖用户认证、数据分页、验证码生成等核心功能模块。
技术架构与环境配置
系统采用B/S架构，后端基于Servlet规范处理HTTP请求，JSP负责视图渲染，MySQL作为持久化存储。开发环境要求JDK 8及以上版本，Tomcat 8+作为Web容器，数据库选用MySQL 5.7或更高版本。
核心功能实现
1. 登录认证与验证码机制
登录模块集成图形验证码功能，防止暴力破解。验证码通过内存图像动态生成，采用随机字符组合：
@WebServlet("/captchaServlet")
public class CaptchaServlet extends HttpServlet {
public void doGet(HttpServletRequest req, HttpServletResponse resp)
throws ServletException, IOException {
// 禁用浏览器缓存
resp.setHeader("Cache-Control", "no-store");
resp.setHeader("Pragma", "no-cache");
resp.setDateHeader("Expires", 0);
int w = 100, h = 40;
BufferedImage img = new BufferedImage(w, h, BufferedImage.TYPE_INT_RGB);
Graphics2D g = img.createGraphics();
// 绘制背景与干扰线
g.setColor(Color.WHITE);
g.fillRect(0, 0, w, h);
g.setColor(Color.LIGHT_GRAY);
for(int i=0; i<30; i++) {
g.drawLine(randomNum(w), randomNum(h), randomNum(w), randomNum(h));
}
// 生成验证码字符串
String code = generateCode(4);
req.getSession().setAttribute("SESS_CAPTCHA", code);
g.setColor(new Color(20, 100, 180));
g.setFont(new Font("微软雅黑", Font.BOLD, 24));
g.drawString(code, 20, 28);
g.dispose();
ImageIO.write(img, "PNG", resp.getOutputStream());
}
private String generateCode(int len) {
String chars = "ABCDEFGHJKMNPQRSTUVWXYZ23456789";
Random rnd = new Random();
StringBuilder sb = new StringBuilder();
for(int i=0; i<len; i++) {
sb.append(chars.charAt(rnd.nextInt(chars.length())));
}
return sb.toString();
}
private int randomNum(int bound) {
return new Random().nextInt(bound);
}
}登录验证Servlet处理用户凭据校验，同时验证图形验证码：
@WebServlet("/authServlet")
public class AuthServlet extends HttpServlet {
protected void doPost(HttpServletRequest req, HttpServletResponse resp)
throws ServletException, IOException {
req.setCharacterEncoding("UTF-8");
HttpSession sess = req.getSession();
// 验证码校验
String inputCode = req.getParameter("captcha");
String sessCode = (String) sess.getAttribute("SESS_CAPTCHA");
sess.removeAttribute("SESS_CAPTCHA"); // 一次性使用
if(sessCode == null || !sessCode.equalsIgnoreCase(inputCode)) {
req.setAttribute("errMsg", "验证码错误或已过期");
req.getRequestDispatcher("/login.jsp").forward(req, resp);
return;
}
// 封装登录实体
Map<String, String[]> params = req.getParameterMap();
Account account = new Account();
try {
BeanUtils.populate(account, params);
} catch(Exception ex) {
ex.printStackTrace();
}
// 业务层验证
AccountService svc = new AccountServiceImpl();
Account user = svc.authenticate(account);
if(user != null) {
sess.setAttribute("currUser", user);
resp.sendRedirect(req.getContextPath() + "/listServlet");
} else {
req.setAttribute("errMsg", "账号或密码不正确");
req.getRequestDispatcher("/login.jsp").forward(req, resp);
}
}
}2. 请求拦截与编码过滤
通过Filter实现全站编码统一与登录状态拦截：
public class SecurityFilter implements Filter {
public void doFilter(ServletRequest req, ServletResponse res, FilterChain chain)
throws IOException, ServletException {
HttpServletRequest request = (HttpServletRequest) req;
HttpServletResponse response = (HttpServletResponse) res;
request.setCharacterEncoding("UTF-8");
response.setCharacterEncoding("UTF-8");
String path = request.getRequestURI();
String action = request.getParameter("action");
// 白名单放行
boolean isPublic = path.endsWith("login.jsp")
|| path.endsWith("register.jsp")
|| path.contains("authServlet")
|| path.contains("captchaServlet")
|| "register".equals(action)
|| path.matches(".*\\.(css|js|png|jpg)$");
if(isPublic || request.getSession().getAttribute("currUser") != null) {
chain.doFilter(req, res);
} else {
response.sendRedirect("login.jsp");
}
}
}3. 学生信息CRUD操作
新增学生记录
@WebServlet("/createServlet")
public class CreateServlet extends HttpServlet {
protected void doPost(HttpServletRequest req, HttpServletResponse resp)
throws ServletException, IOException {
req.setCharacterEncoding("UTF-8");
Map<String, String[]> data = req.getParameterMap();
Student stu = new Student();
try {
BeanUtils.populate(stu, data);
} catch(Exception e) {
e.printStackTrace();
}
StudentService svc = new StudentServiceImpl();
svc.create(stu);
resp.sendRedirect(req.getContextPath() + "/listServlet");
}
}分页查询与条件检索
@WebServlet("/listServlet")
public class ListServlet extends HttpServlet {
protected void doPost(HttpServletRequest req, HttpServletResponse resp)
throws ServletException, IOException {
req.setCharacterEncoding("UTF-8");
String pageNum = req.getParameter("pageNum");
String pageSize = req.getParameter("pageSize");
int num = (pageNum == null || pageNum.isEmpty()) ? 1 : Integer.parseInt(pageNum);
int size = (pageSize == null || pageSize.isEmpty()) ? 10 : Integer.parseInt(pageSize);
Map<String, String[]> criteria = req.getParameterMap();
StudentService svc = new StudentServiceImpl();
PageResult<Student> result = svc.queryByPage(num, size, criteria);
req.setAttribute("pageData", result);
req.setAttribute("searchParams", criteria);
req.getRequestDispatcher("/list.jsp").forward(req, resp);
}
}修改与删除操作
@WebServlet("/modifyServlet")
public class ModifyServlet extends HttpServlet {
protected void doPost(HttpServletRequest req, HttpServletResponse resp)
throws ServletException, IOException {
req.setCharacterEncoding("UTF-8");
Map<String, String[]> data = req.getParameterMap();
Student stu = new Student();
try {
BeanUtils.populate(stu, data);
} catch(Exception e) {
e.printStackTrace();
}
StudentService svc = new StudentServiceImpl();
svc.update(stu);
resp.sendRedirect(req.getContextPath() + "/listServlet");
}
}
@WebServlet("/removeServlet")
public class RemoveServlet extends HttpServlet {
protected void doPost(HttpServletRequest req, HttpServletResponse resp)
throws ServletException, IOException {
String[] ids = req.getParameterValues("stuId");
StudentService svc = new StudentServiceImpl();
svc.batchDelete(ids);
resp.sendRedirect(req.getContextPath() + "/listServlet");
}
}4. 单条记录查询
@WebServlet("/detailServlet")
public class DetailServlet extends HttpServlet {
protected void doPost(HttpServletRequest req, HttpServletResponse resp)
throws ServletException, IOException {
String sid = req.getParameter("sid");
StudentService svc = new StudentServiceImpl();
Student stu = svc.findById(sid);
req.setAttribute("student", stu);
req.getRequestDispatcher("/edit.jsp").forward(req, resp);
}
}用户注册功能
@WebServlet("/signupServlet")
public class SignupServlet extends HttpServlet {
protected void doPost(HttpServletRequest req, HttpServletResponse resp)
throws ServletException, IOException {
req.setCharacterEncoding("UTF-8");
Map<String, String[]> data = req.getParameterMap();
Account acc = new Account();
try {
BeanUtils.populate(acc, data);
} catch(Exception e) {
e.printStackTrace();
}
AccountService svc = new AccountServiceImpl();
svc.register(acc);
resp.sendRedirect(req.getContextPath() + "/login.jsp");
}
}数据库设计要点
系统涉及两张核心数据表：学生信息表（存储学号、姓名、性别、专业、联系方式等字段）与用户表（存储登录账号、加密密码、角色权限等）。建议采用连接池技术管理数据库连接，提升并发性能。
前端交互说明
视图层采用JSP+JSTL技术，通过EL表达式展示后端数据。列表页支持分页导航、条件筛选、批量勾选删除等交互功能。表单提交采用POST方法，配合隐藏域传递记录主键。
