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什么软件做美食视频网站好,无水印logo在线制作免费,王烨娟,网站空间买多大的JavaWeb实现图书管理系统的增删改查与分页 在企业级JavaWeb开发中#xff0c;一个典型的CRUD#xff08;增删改查#xff09;系统不仅是学习技术栈的试金石#xff0c;更是理解MVC分层架构、数据库交互与权限控制的绝佳入口。本文将带你从零构建一个功能完整的图书管理系统…JavaWeb实现图书管理系统的增删改查与分页在企业级JavaWeb开发中一个典型的CRUD增删改查系统不仅是学习技术栈的试金石更是理解MVC分层架构、数据库交互与权限控制的绝佳入口。本文将带你从零构建一个功能完整的图书管理系统涵盖多条件查询、分页展示、登录验证和防重复提交等实用特性。项目采用经典的JSP Servlet JDBC技术组合结合 C3P0 连接池提升数据库性能使用 DBUtils 简化SQL操作并通过 Filter 实现请求拦截完整还原了传统JavaWeb项目的开发流程。整个过程不依赖Spring等高级框架适合初学者掌握底层原理。一、环境准备与依赖配置要运行该项目需确保开发环境中已安装 JDK、Tomcat 和 MySQL。所有第三方库均以 JAR 包形式引入放置于/WEB-INF/lib/目录下即可生效c3p0-0.9.1.2.jar轻量级数据库连接池避免频繁创建连接带来的资源开销。commons-dbutils-1.6.jarApache 提供的 JDBC 工具类极大简化了 ResultSet 到 JavaBean 的映射。jstl.jar与standard.jar支持 JSP 页面中的c:if、c:forEach标签让页面逻辑更清晰。mysql-connector-java-5.1.38-bin.jarMySQL 官方驱动包用于建立数据库连接。这些是经典JavaWeb开发的核心组件在没有ORM框架的时代被广泛使用至今仍具备教学和维护价值。二、数据库设计与初始化系统包含两张核心表books存储图书信息users用于用户登录认证。CREATE DATABASE IF NOT EXISTS library CHARACTER SET utf8 COLLATE utf8_general_ci; USE library; -- 图书表 CREATE TABLE books ( id INT PRIMARY KEY AUTO_INCREMENT, name VARCHAR(100) NOT NULL COMMENT 书名, zuoze VARCHAR(50) NOT NULL COMMENT 作者, price DOUBLE NOT NULL COMMENT 价格, riqi DATE NOT NULL COMMENT 出版日期 ) ENGINEInnoDB DEFAULT CHARSETutf8; -- 用户表 CREATE TABLE users ( yhname VARCHAR(50) PRIMARY KEY COMMENT 用户名, pwd VARCHAR(50) NOT NULL COMMENT 密码 ); -- 插入默认管理员账户 INSERT INTO users VALUES (admin, 123456);⚠️ 注意生产环境中密码应加密存储如MD5或BCrypt此处为演示简化处理。三、Java代码实现实体类定义Book.java表示一本图书的基本属性字段与数据库一一对应。package org.wenyuan.entity; import java.util.Date; public class Book { private int id; private String name; private String zuoze; private double price; private Date riqi; // 构造方法 public Book() {} public Book(String name, String zuoze, double price, Date riqi) { this.name name; this.zuoze zuoze; this.price price; this.riqi riqi; } public Book(int id, String name, String zuoze, double price, Date riqi) { this.id id; this.name name; this.zuoze zuoze; this.price price; this.riqi riqi; } // Getter 和 Setter 方法 public int getId() { return id; } public void setId(int id) { this.id id; } public String getName() { return name; } public void setName(String name) { this.name name; } public String getZuoze() { return zuoze; } public void setZuoze(String zuoze) { this.zuoze zuoze; } public double getPrice() { return price; } public void setPrice(double price) { this.price price; } public Date getRiqi() { return riqi; } public void setRiqi(Date riqi) { this.riqi riqi; } Override public String toString() { return Book [id id , name name , zuoze zuoze , price price , riqi riqi ]; } }User.java用户实体仅包含用户名和密码。package org.wenyuan.entity; public class User { private String yhname; private String pwd; public User() {} public User(String yhname, String pwd) { this.yhname yhname; this.pwd pwd; } public String getYhname() { return yhname; } public void setYhname(String yhname) { this.yhname yhname; } public String getPwd() { return pwd; } public void setPwd(String pwd) { this.pwd pwd; } }BookPage.java封装分页与搜索条件的对象是前后端数据交换的关键载体。package org.wenyuan.entity; import java.util.ArrayList; import java.util.List; public class BookPage { private String key; private String zuoze; private double minprice; private double maxprice; private int pageNo; private int pageSize; private int maxPagNo; private ListBook books new ArrayList(); // getter/setter... public String getKey() { return key; } public void setKey(String key) { this.key key; } public String getZuoze() { return zuoze; } public void setZuoze(String zuoze) { this.zuoze zuoze; } public double getMinprice() { return minprice; } public void setMinprice(double minprice) { this.minprice minprice; } public double getMaxprice() { return maxprice; } public void setMaxprice(double maxprice) { this.maxprice maxprice; } public int getPageNo() { return pageNo; } public void setPageNo(int pageNo) { this.pageNo pageNo; } public int getPageSize() { return pageSize; } public void setPageSize(int pageSize) { this.pageSize pageSize; } public int getMaxPagNo() { return maxPagNo; } public void setMaxPagNo(int maxPagNo) { this.maxPagNo maxPagNo; } public ListBook getBooks() { return books; } public void setBooks(ListBook books) { this.books books; } public BookPage() {} }数据访问层DAOBookDao.java基于 DBUtils 封装对books表的操作。其中getPage()方法实现了带条件的分页查询。package org.wenyuan.dao; import java.sql.ResultSet; import java.sql.SQLException; import java.util.ArrayList; import java.util.List; import java.util.Map; import org.apache.commons.dbutils.QueryRunner; import org.apache.commons.dbutils.handlers.BeanHandler; import org.apache.commons.dbutils.handlers.MapListHandler; import org.apache.commons.dbutils.handlers.ScalarHandler; import org.wenyuan.entity.Book; import org.wenyuan.entity.BookPage; import org.wenyuan.util.JdbcUtil; public class BookDao { QueryRunner qr JdbcUtil.qr; public void insert(Book book) throws SQLException { String sql INSERT INTO books VALUES(NULL, ?, ?, ?, ?); qr.update(sql, book.getName(), book.getZuoze(), book.getPrice(), book.getRiqi()); } public void delete(int id) throws SQLException { String sql DELETE FROM books WHERE id?; qr.update(sql, id); } public void update(Book book) throws SQLException { String sql UPDATE books SET name?, zuoze?, price?, riqi? WHERE id?; qr.update(sql, book.getName(), book.getZuoze(), book.getPrice(), book.getRiqi(), book.getId()); } public Book get(int id) throws SQLException { String sql SELECT * FROM books WHERE id?; BeanHandlerBook rsh new BeanHandler(Book.class); return qr.query(sql, rsh, id); } public ListBook getAll() throws SQLException { MapListHandler rsh new MapListHandler(); String sql SELECT * FROM books; ListMapString, Object list qr.query(sql, rsh); ListBook books new ArrayList(); for (MapString, Object map : list) { books.add(mapToBook(map)); } return books; } private Book mapToBook(MapString, Object map) { if (map.isEmpty()) return null; Book book new Book(); try { Class? c Book.class; for (Map.EntryString, Object entry : map.entrySet()) { String fieldName entry.getKey(); Object fieldValue entry.getValue(); java.lang.reflect.Field field c.getDeclaredField(fieldName); field.setAccessible(true); field.set(book, fieldValue); } } catch (Exception e) { e.printStackTrace(); } return book; } public void getPage(BookPage bp) throws SQLException { String key bp.getKey(); String zuoze bp.getZuoze(); double minPrice bp.getMinprice(); double maxPrice bp.getMaxprice(); int pageNo bp.getPageNo(); int pageSize bp.getPageSize(); String sql1 SELECT * FROM books WHERE (name LIKE ? OR zuoze LIKE ?) AND zuoze LIKE ? AND price ? AND price ? LIMIT ?, ?; MapListHandler rsh new MapListHandler(); ListMapString, Object list qr.query(sql1, rsh, % key %, % key %, % zuoze %, minPrice, maxPrice, (pageNo - 1) * pageSize, pageSize); ListBook books new ArrayList(); for (MapString, Object map : list) { books.add(mapToBook(map)); } bp.setBooks(books); String sql2 SELECT COUNT(*) FROM books WHERE (name LIKE ? OR zuoze LIKE ?) AND zuoze LIKE ? AND price ? AND price ?; ScalarHandlerLong rsh2 new ScalarHandler(); Long count qr.query(sql2, rsh2, % key %, % key %, % zuoze %, minPrice, maxPrice); int maxPageNo (int)(count % pageSize 0 ? count / pageSize : count / pageSize 1); bp.setMaxPagNo(maxPageNo); } }UserDao.java负责用户登录验证。package org.wenyuan.dao; import java.sql.Connection; import java.sql.PreparedStatement; import java.sql.ResultSet; import java.sql.SQLException; import org.wenyuan.entity.User; import org.wenyuan.util.JdbcUtil; public class UserDao { public User login(String userName, String userPwd) throws SQLException { Connection conn JdbcUtil.getConnection(); String sql SELECT yhname, pwd FROM users WHERE yhname? AND pwd?; PreparedStatement ps conn.prepareStatement(sql); ps.setString(1, userName); ps.setString(2, userPwd); ResultSet rs ps.executeQuery(); User u null; if (rs.next()) { u new User(rs.getString(1), rs.getString(2)); } rs.close(); ps.close(); conn.close(); return u; } }业务逻辑层ServiceBookService.java调用 DAO 层完成具体业务异常统一捕获并打印日志。package org.wenyuan.service; import java.sql.SQLException; import java.util.List; import org.wenyuan.dao.BookDao; import org.wenyuan.entity.Book; import org.wenyuan.entity.BookPage; public class BookService { private BookDao dao new BookDao(); public void insertOrUpdate(Book book) { try { if (book.getId() ! 0) { dao.update(book); } else { dao.insert(book); } } catch (SQLException e) { e.printStackTrace(); } } public void delete(int id) { try { dao.delete(id); } catch (SQLException e) { e.printStackTrace(); } } public Book get(int id) { try { return dao.get(id); } catch (SQLException e) { e.printStackTrace(); } return null; } public ListBook getAll() { try { return dao.getAll(); } catch (SQLException e) { e.printStackTrace(); } return null; } public void getPage(BookPage bp) { try { dao.getPage(bp); } catch (SQLException e) { e.printStackTrace(); } } }UserService.java封装用户登录逻辑。package org.wenyuan.service; import java.sql.SQLException; import org.wenyuan.dao.UserDao; import org.wenyuan.entity.User; public class UserService { public User user(String username, String pwd) { try { return new UserDao().login(username, pwd); } catch (SQLException e) { e.printStackTrace(); } return null; } }控制器层ServletBookServlet.java采用反射机制动态调用方法减少冗余代码。package org.wenyuan.serlvet; import java.io.IOException; import java.lang.reflect.InvocationTargetException; import java.lang.reflect.Method; import java.text.SimpleDateFormat; import java.util.Date; 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 org.wenyuan.entity.Book; import org.wenyuan.entity.BookPage; import org.wenyuan.entity.User; import org.wenyuan.service.BookService; import org.wenyuan.util.DataUtil; WebServlet(/BookServlet/*) public class BookServlet extends HttpServlet { private static final long serialVersionUID 1L; protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { String uri request.getRequestURI(); String methodName uri.substring(uri.lastIndexOf(/) 1); try { Method method getClass().getDeclaredMethod(methodName, HttpServletRequest.class, HttpServletResponse.class); method.invoke(this, request, response); } catch (Exception e) { e.printStackTrace(); } } protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { doGet(request, response); } public void submit(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { HttpSession session request.getSession(); String token (String) session.getAttribute(code); String vCode request.getParameter(vCode); if (!vCode.equalsIgnoreCase(token)) { response.sendRedirect(request.getContextPath() /info.jsp); return; } if (token ! null) { session.removeAttribute(code); String id request.getParameter(id); String name request.getParameter(name); String zuoze request.getParameter(zuoze); String price request.getParameter(price); String dateStr request.getParameter(date); Date birth DataUtil.testStringToDate(dateStr); Book book new Book(name, zuoze, Double.parseDouble(price), birth); if (id ! null !id.trim().isEmpty()) { book.setId(Integer.parseInt(id)); } new BookService().insertOrUpdate(book); response.sendRedirect(request.getContextPath() /index.jsp); } } public void delete(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { String id request.getParameter(id); new BookService().delete(Integer.parseInt(id)); response.sendRedirect(request.getContextPath() /index.jsp); } public void update(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { String strId request.getParameter(id); Book book new BookService().get(Integer.parseInt(strId)); request.setAttribute(book, book); request.getRequestDispatcher(/m.jsp).forward(request, response); } public void getAll(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { String key request.getParameter(key) null ? : request.getParameter(key); String zuoze request.getParameter(zuoze) null ? : request.getParameter(zuoze); String minPrice request.getParameter(minPrice); String maxPrice request.getParameter(maxPrice); if (minPrice null || minPrice.trim().isEmpty()) minPrice 0; if (maxPrice null || maxPrice.trim().isEmpty()) maxPrice Double.MAX_VALUE ; int pageNo Integer.parseInt(request.getParameter(pageNo)); int pageSize Integer.parseInt(request.getParameter(pageSize)); BookPage bp new BookPage(key, zuoze, Double.parseDouble(minPrice), Double.parseDouble(maxPrice), pageNo, pageSize); new BookService().getPage(bp); request.setAttribute(books, bp); request.getRequestDispatcher(/all.jsp).forward(request, response); } }Deng.java登录处理package org.wenyuan.serlvet; import java.io.IOException; import javax.servlet.ServletException; import javax.servlet.annotation.WebServlet; import javax.servlet.http.Cookie; import javax.servlet.http.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import javax.servlet.http.HttpSession; import org.wenyuan.entity.User; import org.wenyuan.service.UserService; WebServlet(/Deng) public class Deng extends HttpServlet { private static final long serialVersionUID 1L; protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { String username request.getParameter(yhname); String pwd request.getParameter(pwd); User u new UserService().user(username, pwd); if (u ! null) { HttpSession session request.getSession(); session.setAttribute(user, u); session.setMaxInactiveInterval(1800); Cookie cookie new Cookie(JSESSIONID, session.getId()); cookie.setPath(/); cookie.setMaxAge(1800); response.addCookie(cookie); response.sendRedirect(request.getContextPath() /index.jsp); } else { response.sendRedirect(sb.jsp); } } protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { doGet(request, response); } }ValidateCodeServlet.java验证码生成防止机器人暴力提交。package org.wenyuan.serlvet; 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; import org.wenyuan.util.ValidateCode; WebServlet(/vCode) public class ValidateCodeServlet extends HttpServlet { private static final long serialVersionUID 1L; Override protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { response.setContentType(image/jpeg); response.setHeader(Pragma, no-cache); response.setHeader(Cache-Control, no-cache); response.setDateHeader(Expires, 0); HttpSession session request.getSession(); ValidateCode vCode new ValidateCode(120, 40, 5, 150); session.setAttribute(code, vCode.getCode()); vCode.write(response.getOutputStream()); } }工具类JdbcUtil.javaC3P0 配置与全局 QueryRunner 实例。package org.wenyuan.util; import com.mchange.v2.c3p0.ComboPooledDataSource; import org.apache.commons.dbutils.QueryRunner; import java.sql.Connection; import java.sql.SQLException; public class JdbcUtil { private static ComboPooledDataSource ds new ComboPooledDataSource(); public static final QueryRunner qr new QueryRunner(ds); static { try { ds.setDriverClass(com.mysql.jdbc.Driver); ds.setJdbcUrl(jdbc:mysql://localhost:3306/library?useSSLfalsecharacterEncodingutf8); ds.setUser(root); ds.setPassword(your_password); // 修改为你的密码 } catch (Exception e) { throw new ExceptionInInitializerError(e); } } public static Connection getConnection() throws SQLException { return ds.getConnection(); } }DataUtil.java字符串转日期工具。package org.wenyuan.util; import java.text.SimpleDateFormat; import java.util.Date; public class DataUtil { public static Date testStringToDate(String src) { SimpleDateFormat format new SimpleDateFormat(yyyy-MM-dd); try { return format.parse(src); } catch (Exception e) { e.printStackTrace(); return null; } } }四、前端页面实现JSPindex.jsp首页自动跳转至图书列表。jsp:forward pageBookServlet/getAll?keyzuozeminPricemaxPricepageNo1pageSize5/denglu.jsp登录页form actionDeng table trtd用户名/tdtdinput typetext nameyhname/td/tr trtd密 码/tdtdinput typepassword namepwd/td/tr trtdinput typesubmit value登录/td/tr /table /formall.jsp主列表页集成搜索框、分页控件与数据表格。c:if test${user.yhnamenull} a hrefdenglu.jsp登录/a /c:if c:otherwise span欢迎你${user.yhname}/span a hrefm.jsp添加/a /c:otherwise input typetext idkey value${books.key} input typetext idzuoze value${books.zuoze} input typetext idminPrice value${books.minprice eq 0 ? : books.minprice} input typetext idmaxPrice value${books.maxprice eq 9.17578e307 ? : books.maxprice} a href# idsearch查询/a a href# idfirstPage首页/a a href# idprePage上一页/a a href# idnextPage下一页/a a href# idlastPage末页/a 共 ${books.pageNo}/${books.maxPagNo} 页 table border1 tr thID/thth书名/thth作者/thth价格/thth日期/thth操作/th /tr c:forEach items${books.books} varb tr td${b.id}/td td${b.name}/td td${b.zuoze}/td td${b.price}/td td${b.riqi}/td td a hrefBookServlet/delete?id${b.id}删除/a a hrefBookServlet/update?id${b.id}修改/a a hrefCheck?id${b.id}查看/a /td /tr /c:forEach /tablem.jsp新增/修改页根据是否存在book对象判断当前是新增还是编辑状态。h1${empty book ? 新增 : 修改} 图书/h1 form actionBookServlet/submit c:if test${not empty book} input typehidden nameid value${book.id} /c:if 书名input typetext namename value${book.name}br 作者input typetext namezuoze value${book.zuoze}br 价格input typetext nameprice value${book.price}br 日期input typedate namedate value${book.riqi}br 验证码input typetext namevCodeimg srcvCode onclickthis.srcvCode?new Date() alt验证码br input typesubmit value提交 /form五、安全控制 —— 权限过滤器通过Filter拦截所有对图书操作的请求未登录用户将被重定向到登录页。WebFilter(/BookServlet/*) public class AllFilter implements javax.servlet.Filter { public void doFilter(ServletRequest req, ServletResponse resp, FilterChain chain) throws IOException, ServletException { HttpServletRequest request (HttpServletRequest) req; User u (User) request.getSession().getAttribute(user); if (u null) { ((HttpServletResponse) resp).sendRedirect(request.getContextPath() /denglu.jsp); return; } chain.doFilter(req, resp); } }只需在类上添加注解即可启用无需在 web.xml 中额外配置Servlet 3.0 支持。这套图书管理系统虽然基于传统技术栈但其分层清晰、结构规范非常适合作为学习案例。它展示了如何在没有现代框架的情况下手动组织代码实现模块化与可维护性。对于理解 Web 请求生命周期、会话管理、数据库连接优化等核心概念具有重要价值。随着技术演进我们可以在此基础上逐步引入 Spring MVC 替代原生 Servlet用 MyBatis 或 JPA 替换 DBUtils前端也可升级为 Ajax 异步加载甚至整合 Vue/React 构建前后端分离应用。这种渐进式重构思维正是工程师成长的真实路径。