这里写目录标题

• 一、数据库准备和创建安全jsp与servlet完成用户登录
• 二、数据库表的创建
• 三、核心代码如下
• • • ①dao层相关代码
    • ②entity层相关代码
    • ③filter层相关代码
    • ④servlet层相关代码
    • ⑤WEB-INF下面的jsp目录文件
    • ⑥WEB-INF下面的lib目录文件
    • ⑦web.xml
• 四、系统测试结果展示如下：

一、数据库准备和创建安全jsp与servlet完成用户登录 ??1.数据库准备步骤地址
??2.安全jsp与servlet创建过程
二、数据库表的创建
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三、核心代码如下
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①dao层相关代码
1.UserDao

package com.allen.dao; import com.allen.entity.User; import java.security.MessageDigest; import java.security.NoSuchAlgorithmException; import java.sql.*; public class UserDao { public User login(String loginName,String loginPassword) throws ClassNotFoundException, SQLException, NoSuchAlgorithmException { Class.forName("com.mysql.jdbc.Driver"); Connection connection = DriverManager.getConnection("jdbc:mysql:///picture?useSSL=false", "root", "123456"); PreparedStatement statement = connection.prepareStatement("select * from user where login_name=? and login_password=?"); statement.setObject(1,loginName); statement.setObject(2,loginPassword); ResultSet resultSet = statement.executeQuery(); User user=null; if (resultSet.next()) { user = new User(); user.setId(resultSet.getInt("id")); user.setTrueName(resultSet.getString("true_name")); user.setEmail(resultSet.getString("email")); user.setLoginName(resultSet.getString("login_name")); user.setLoginPassword(resultSet.getString("login_password")); user.setTelephone(resultSet.getString("telephone")); } resultSet.close(); statement.close(); connection.close(); return user; } //MD5加密方法 private String md5(String loginPassword) throws NoSuchAlgorithmException { StringBuffer stringBuffer = new StringBuffer(32); MessageDigest md5 = MessageDigest.getInstance("MD5"); byte[] bytes = md5.digest(loginPassword.getBytes()); for (int i = 0; i < bytes.length; i++) { stringBuffer.append(Integer.toHexString((bytes[i]&0xFF)|0x100).toUpperCase(),1,3); } return stringBuffer.toString(); } }

2.ImageDao

package com.allen.dao; import com.allen.entity.Image; import java.sql.*; import java.util.ArrayList; import java.util.List; public class ImageDao { public boolean add(Image image) throws ClassNotFoundException, SQLException { Class.forName("com.mysql.jdbc.Driver"); Connection connection = DriverManager.getConnection("jdbc:mysql:///picture?useSSL=false", "root", "123456"); PreparedStatement statement = connection.prepareStatement("insert into image (original_file_name,relative_paths,create_time,user_id) values (?,?,now(),?)"); statement.setObject(1,image.getOriginalFileName()); statement.setObject(2,image.getRelativePaths()); statement.setObject(3,image.getUserId()); int i = statement.executeUpdate(); statement.close(); connection.close(); return i!=0; }public List list() throws ClassNotFoundException, SQLException { Class.forName("com.mysql.jdbc.Driver"); Connection connection = DriverManager.getConnection("jdbc:mysql:///picture?useSSL=false", "root", "123456"); PreparedStatement statement = connection.prepareStatement("select * from image"); ResultSet resultSet = statement.executeQuery(); List list=new ArrayList<>(); while (resultSet.next()) { Image image = new Image(); image.setUserId(resultSet.getInt("user_id")); image.setRelativePaths(resultSet.getString("relative_paths")); image.setOriginalFileName(resultSet.getString("original_file_name")); image.setId(resultSet.getInt("id")); image.setCreateTime(resultSet.getTime("create_time")); list.add(image); } resultSet.close(); statement.close(); connection.close(); return list; } }

②entity层相关代码
1.Image

package com.allen.entity; import java.util.Date; public class Image {private Integer id; private String originalFileName; private String relativePaths; private Date createTime; private Integer userId; public Integer getId() { return id; }public void setId(Integer id) { this.id = id; }public String getOriginalFileName() { return originalFileName; }public void setOriginalFileName(String originalFileName) { this.originalFileName = originalFileName; }public String getRelativePaths() { return relativePaths; }public void setRelativePaths(String relativePaths) { this.relativePaths = relativePaths; }public Date getCreateTime() { return createTime; }public void setCreateTime(Date createTime) { this.createTime = createTime; }public Integer getUserId() { return userId; }public void setUserId(Integer userId) { this.userId = userId; } }

2.User

package com.allen.entity; public class User { private Integer id; private String trueName; private String loginName; private String loginPassword; private String telephone; private String email; public Integer getId() { return id; }public void setId(Integer id) { this.id = id; }public String getTrueName() { return trueName; }public void setTrueName(String trueName) { this.trueName = trueName; }public String getLoginName() { return loginName; }public void setLoginName(String loginName) { this.loginName = loginName; }public String getLoginPassword() { return loginPassword; }public void setLoginPassword(String loginPassword) { this.loginPassword = loginPassword; }public String getTelephone() { return telephone; }public void setTelephone(String telephone) { this.telephone = telephone; }public String getEmail() { return email; } public void setEmail(String email) { this.email = email; } }

③filter层相关代码
1.LoginFilter

package com.allen.filter; import javax.servlet.*; import javax.servlet.annotation.WebFilter; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import java.io.IOException; @WebFilter("/*") public class LoginFilter implements Filter { @Override public void init(FilterConfig filterConfig) throws ServletException {}@Override public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException { HttpServletRequest request= (HttpServletRequest) servletRequest; HttpServletResponse response= (HttpServletResponse) servletResponse; if (request.getRequestURI().endsWith("login")) { filterChain.doFilter(request,response); return; }if (request.getSession().getAttribute("UserInfo")!=null) { filterChain.doFilter(request,response); return; } response.sendRedirect(request.getContextPath()+"/login"); } @Override public void destroy() {} }

④servlet层相关代码
1.IndexServlet

package com.allen.servlet; import com.allen.dao.ImageDao; import com.allen.entity.Image; import com.allen.entity.User; import javax.servlet.ServletException; import javax.servlet.annotation.MultipartConfig; import javax.servlet.annotation.WebServlet; import javax.servlet.http.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import javax.servlet.http.Part; import java.io.IOException; import java.sql.SQLException; import java.util.List; import java.util.UUID; @WebServlet("/index") @MultipartConfig public class IndexServlet extends HttpServlet { ImageDao imageDao = new ImageDao(); @Override protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { try { List list = imageDao.list(); request.setAttribute("imageLsit",list); request.getRequestDispatcher("/WEB-INF/jsp/index.jsp").forward(request,response); }catch (Exception e){ e.printStackTrace(); } } @Override protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { request.setCharacterEncoding("UTF-8"); response.setCharacterEncoding("UTF-8"); Part file = request.getPart("file"); String uuid = UUID.randomUUID().toString().replaceAll("-", ""); String fileName = file.getSubmittedFileName(); String type = fileName.substring(fileName.lastIndexOf(".")); file.write("H:\\demotest\\picture-system\\images\\"+uuid+type); Image image = new Image(); image.setOriginalFileName(fileName); image.setRelativePaths("/images/"+uuid+type); User userInfo = (User) request.getSession().getAttribute("UserInfo"); image.setUserId(userInfo.getId()); try { imageDao.add(image); response.sendRedirect(request.getContextPath()+"/index"); } catch (ClassNotFoundException e) { e.printStackTrace(); } catch (SQLException throwables) { throwables.printStackTrace(); } } }

2.LoginServlet

package com.allen.servlet; import com.allen.dao.UserDao; import com.allen.entity.User; 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; @WebServlet("/login") public class LoginServlet extends HttpServlet { UserDao userDao = new UserDao(); @Override protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { request.getRequestDispatcher("/WEB-INF/jsp/login.jsp").forward(request,response); }@Override protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { request.setCharacterEncoding("UTF-8"); response.setCharacterEncoding("UTF-8"); String username = request.getParameter("username"); String password = request.getParameter("password"); try { User user = userDao.login(username, password); if (user!=null) { request.getSession().setAttribute("UserInfo",user); response.sendRedirect(request.getContextPath()+"/index"); return; } request.setAttribute("username",username); request.setAttribute("password",password); request.setAttribute("msg","账号或密码错误！！！请重新输入"); request.getRequestDispatcher("/WEB-INF/jsp/login.jsp").forward(request,response); }catch(Exception e){ e.printStackTrace(); } } }

3.LogoutServlet

package com.allen.servlet; 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; @WebServlet("/logout") public class LogoutServlet extends HttpServlet { @Override protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { request.getSession().invalidate(); request.getRequestDispatcher("/WEB-INF/jsp/login.jsp").forward(request,response); } }

⑤WEB-INF下面的jsp目录文件
1.login.jsp

> h4{ text-align: center; }

登录页面

记住我

登录 ${msg}

2.index.jsp

="http://apps.bdimg.com/libs/jquery/2.1.4/jquery.min.js"> > $(document).ready(function () { //首先将#back-to-top隐藏 $("#back-to-top").hide(); //当滚动条的位置处于距顶部600像素以下时，跳转链接出现，否则消失 $(function () { $(window).scroll(function () { if ($(window).scrollTop() > 300) { $("#back-to-top").fadeIn(500); } else { $("#back-to-top").fadeOut(500); } }); //当点击跳转链接后，回到页面顶部位置 $("#back-to-top").click(function () { $('body,html').animate({ scrollTop: 0 }, 500); return false; }); }); }); > p#back-to-top { position: fixed; bottom: 30px; right: 12px; }p#back-to-top a { text-align: center; text-decoration: none; color: #000; display: block; width: 60px; /*使用CSS3中的transition属性给跳转链接中的文字添加渐变效果*/ -moz-transition: color1s; -webkit-transition: color1s; -o-transition: color1s; }p#back-to-top a:hover { color: #000011; }p#back-to-top a span { background-color: #d4bbbb; z-index: -100; border: 1px solid #cccccc; border-radius: 6px; display: block; height: 30px; width: 30px; margin-bottom: 5px; /*使用CSS3中的transition属性给标签背景颜色添加渐变效果*/ -moz-transition: background1s; -webkit-transition: background1s; -o-transition: background1s; }#back-to-top a:hover span { background-color: #f0f0f0; }

文件

上传 ="position: fixed; right: 140px"> 退出登录

文章图片
${z.originalFileName}${z.createTime}

class="fa fa-chevron-up" aria-hidden="true" style="width: 80px; height: 30px; ">返回顶部

⑥WEB-INF下面的lib目录文件
jstl-1.2.jar
mysql-connector-java-5.1.48.jar
⑦web.xml

login

四、系统测试结果展示如下： 测试视频

简单的上传图片系统

【Jsp与Servlet|使用安全 jsp 与 servlet 完成用户登录（登录错误时账号密码回填）。登录成功后才能上传图片的图片管理系统。】视频地址：

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