jdbc实现图书馆借阅系统

/** *  * 对数据库的操作进行单独处理，更多的逻辑更改在更高的逻辑层编写。降低耦合 * */public class LibararyDao {  /**   * 注册图书   * @param user 注册图书信息   * @return   */  public boolean addBook(Bookinfo bookinfo){    try {      Connection con =JDBCutil.creatConnection();      String sql = "insert into bookinfo (bookname,zuozhe,shuliang,shengyushuliang,date)"          + " values (?,?,?,?,?) ";      PreparedStatement pre =con.prepareStatement(sql);      pre.setString(1, bookinfo.getBookname());      pre.setString(2, bookinfo.getZuozhe());      pre.setInt(3, bookinfo.getShuliang());      pre.setInt(4, bookinfo.getShuliang());      pre.setDate(5, new java.sql.Date(bookinfo.getData().getTime()));      pre.execute();    } catch (SQLException e) {      System.out.println("图书注册失败");      e.printStackTrace();      return false;    }    return true;  }  /**   * 注册账号   * @param user 注册信息   * @return   */  public boolean addUser(User user){    try {      Connection con =JDBCutil.creatConnection();      String sql = "insert into userinfo (username,password,books) values (?,?,0) ";      PreparedStatement pre =con.prepareStatement(sql);      pre.setString(1, user.getUsername());      pre.setString(2, user.getPassword());      pre.execute();    } catch (SQLException e) {      System.out.println("注册失败");      e.printStackTrace();      return false;    }    return true;  }  /**   * 查询用户   * @param user 信息   * @return   */  public ResultSet queryUser(User user){    try {      Connection con =JDBCutil.creatConnection();      String sql = "select * from userinfo where username = ? ";      PreparedStatement pre;      pre = con.prepareStatement(sql);      pre.setString(1, user.getUsername());      ResultSet r =pre.executeQuery();      return r;    } catch (SQLException e) {      System.out.println("查询失败");      e.printStackTrace();      return null;    }  }  /**   * 更新持有书   * @param user 信息   * @return   */  public boolean updateUserbooks(User user){    try {      Connection con =JDBCutil.creatConnection();      String sql = "update userinfo set books = ? where username = ? ";      PreparedStatement pre;      pre = con.prepareStatement(sql);      pre.setInt(1, user.getBooks());      pre.setString(2, user.getUsername());      int r =pre.executeUpdate();      if(r>0){        return true;      }else{        return false;      }    } catch (SQLException e) {      System.out.println("查询失败");      e.printStackTrace();      return false;    }  }  /**   * 借书表中插入   * @param username 借书人   * @param bookname 书名   * @return   */  public boolean addborrowinfo(String username,String bookname){    try {      Connection con =JDBCutil.creatConnection();      String sql = "insert into borrowinfo (username,bookname,borrowdate,returndate)"          + " values (?,?,?,?) ";      PreparedStatement pre;      pre = con.prepareStatement(sql);      pre.setString(1, username);      pre.setString(2, bookname);      pre.setDate(3, new java.sql.Date(new Date().getTime()));      pre.setDate(4, new java.sql.Date(DateUtil.addMonth(new Date()).getTime()));      pre.execute();    } catch (SQLException e) {      System.out.println("借书失败");      e.printStackTrace();      return false;    }    return true;  }  /**   * 查书   * @param bookname 书名   * @return   */  public ResultSet queryBook(String bookname){    try {      Connection con =JDBCutil.creatConnection();      String sql = "select * from bookinfo where bookname ='"+bookname+"'";      PreparedStatement pre;      pre = con.prepareStatement(sql);      ResultSet r =pre.executeQuery();      return r;    }    catch (SQLException e) {      System.out.println("借书失败");      e.printStackTrace();      return null;    }}  /**   * 查询所有的书籍   * @return   */  public ResultSet queryAllBook(){    try {      Connection con =JDBCutil.creatConnection();      String sql = "select * from bookinfo ";      PreparedStatement pre;      pre = con.prepareStatement(sql);      ResultSet r =pre.executeQuery();      return r;    }    catch (SQLException e) {      System.out.println("借书失败");      e.printStackTrace();      return null;    }  }  /**   * 分页    * @param page   * @return   */    public ResultSet querySubBookInfo(int page){      try {        Connection con =JDBCutil.creatConnection();        PreparedStatement pre;        String sql = "select * from bookinfo limit ?,5 ";        pre = con.prepareStatement(sql);        pre.setInt(1, page);        ResultSet r =pre.executeQuery();        return r;      }      catch (SQLException e) {        System.out.println("借书失败");        e.printStackTrace();        return null;      }  }  /**   * 数据页数 五条数据为一组   * @return   */  public int queryPageInfo(){    try {      int zongshu = 0;      Connection con =JDBCutil.creatConnection();      String sql1 = "select count(id) as cou from bookinfo ";      Statement sta =con.createStatement();      ResultSet res =sta.executeQuery(sql1);      if(res.next())      {        zongshu = res.getInt("cou");        if(zongshu == 0)return 0;      }      int a =0;      if(zongshu%5==0){        a = zongshu/5;      }else{        a = zongshu/5+1;      }      return a;    }    catch (SQLException e) {      System.out.println("借书失败");      e.printStackTrace();      return -1;    }  }  /**   * 更新剩余数量   * @param bookname 书名   * @param sysl 数量   * @return   */  public boolean updateBookinfo(String bookname,int sysl){    try {      Connection con =JDBCutil.creatConnection();      String sql = "update bookinfo set shengyushuliang = ? where bookname = ?";      PreparedStatement pre;      pre = con.prepareStatement(sql);      pre.setInt(1,sysl);      pre.setString(2, bookname);      int r =pre.executeUpdate();      if(r>0){        return true;      }else{        return false;      }    } catch (SQLException e) {      System.out.println("借书失败");      e.printStackTrace();      return false;    }    }    /*public boolean queryBook(String...strings){      try {        Connection con =JDBCutil.creatConnection();        String sql = "select bookname from bookinfo where 1=1 ";        PreparedStatement pre;        pre = con.prepareStatement(sql);        ResultSet r =pre.executeQuery();        if(r.next()){          return true;        }else{          return false;        }      } catch (SQLException e) {        System.out.println("借书失败");        e.printStackTrace();        return false;      }*/    /**     * 查询用户的所有的借阅信息      * @param username     * @return     */  public ResultSet queryBorrowinfo(String username){    try {      Connection con =JDBCutil.creatConnection();      String sql = "select * from borrowinfo where username = '"+username+"'";      PreparedStatement pre = con.prepareStatement(sql);      ResultSet r =pre.executeQuery();      return r;    } catch (SQLException e) {      System.out.println("查询失败");      e.printStackTrace();      return null;    }  }  /**   * 查询借阅信息   * @param username   * @return   */  public ResultSet queryBorrowinfo(String username,String bookname){    try {      Connection con =JDBCutil.creatConnection();      String sql = "select * from borrowinfo where username = ? and bookname = ?";      PreparedStatement pre = con.prepareStatement(sql);      pre.setString(1, username);      pre.setString(2, bookname);      ResultSet r =pre.executeQuery();      return r;    } catch (SQLException e) {      System.out.println("查询失败");      e.printStackTrace();      return null;    }  }  /**   * 删除借书   * @param username 人名   * @param bookname 书名   * @return   */  public boolean deleteBorrowInfo(String username,String bookname){    try {      Connection con =JDBCutil.creatConnection();      String sql = "delete from borrowinfo where username = ? and bookname = ? ";      PreparedStatement pre = con.prepareStatement(sql);      pre.setString(1, username);      pre.setString(2, bookname);      pre.execute();      return true;    } catch (SQLException e) {      System.out.println("查询失败");      e.printStackTrace();      return false;    }  }}

/** * asdfasd 发斯蒂芬 *  */package library.controller;import java.sql.ResultSet;import java.sql.SQLException;import java.util.ArrayList;import java.util.List;import java.util.Scanner;import library.dao.LibararyDao;import library.po.Bookinfo;import library.po.BorrowInfo;import library.po.User;public class BookController {  private static LibararyDao bookdao;  private BorrowInfo b;  public BookController() {    if(bookdao == null) bookdao = new LibararyDao();  }  public static void main(String[] args) {  //System.out.println(new BookController().addUser(new User("123", "dvdf")));      //System.out.println(new BookController().borrowBook("123", new User("123", "dvdf")));  // new BookController().fenyeInfo(2);  }  /**   * 用户登录   * @param user 传过来的账号密码   * @return 返回1为登陆成功 2为不存在 3异常   */  public int loginUser(User user){    ResultSet rs =bookdao.queryUser(user);//验证用户是否存在    try {      if(rs!=null&&rs.next()){        boolean b =rs.getString("password").equals(user.getPassword());        if(b){          return 1;        }      }      return 2;    } catch (SQLException e) {      e.printStackTrace();      return 3;    }    }  /**   * 管理员登陆   * @param user 传过来的账号密码   * @return 返回1为登陆成功 2为不存在 3异常   */  public int loginGuanli(User user){    ResultSet rs =bookdao.queryUser(user);//验证管理员是否存在    try {      if(rs!=null&&rs.next()){        boolean b =rs.getString("password").equals(user.getPassword());        int b1 = rs.getInt("isguanli");//管理员标志位1        if(b&&b1==1){          return 1;        }      }return 2;    } catch (SQLException e) {      // TODO Auto-generated catch block      e.printStackTrace();      return 3;    }    }  /**   * 查询书籍列表   * @return 返回1为查询成功并已经输出 2为失败或其他   */  public int queryBookinfo(){    try {      ResultSet r =bookdao.queryAllBook();      while(r!=null&&r.next()){        System.out.println("书名"+r.getString("bookname")+"作者"+            r.getString("zuozhe")+"总数"+r.getInt("shuliang")+"剩余数量"+r.getInt("shengyushuliang"));      }      if(r==null)return 2;      return 1;    } catch (SQLException e) {      // TODO Auto-generated catch block      e.printStackTrace();      return 2;    }  }  /**   * 查询书籍数量和剩余数量   * @return 返回1为查询成功并已经输出 2为失败或其他   */  public ResultSet queryBookK(String bookname){      ResultSet r =bookdao.queryBook(bookname);      return r;  }  /**   * 查询书籍   * @return 返回1为查询成功并已经输出 2为失败或其他   */  public int queryBook(String bookname){    try {      ResultSet r =bookdao.queryBook(bookname);      while(r!=null&&r.next()){        System.out.println("书名"+r.getString("bookname")+"作者"+            r.getString("zuozhe")+"总数"+r.getInt("shuliang")+"剩余数量"+r.getInt("shengyushuliang"));      }      if(r==null)return 2;      return 1;    } catch (SQLException e) {      // TODO Auto-generated catch block      e.printStackTrace();      return 2;    }  }  /**   * 加入新的图书信息   * @param bookinfo 书籍的详细信息   * @return 1成功 2失败   */  public int addBookinfo(Bookinfo bookinfo){    boolean b = bookdao.addBook(bookinfo);    if(b)return 1;    return 2;  }  /**   * 注册用户   * @param user   * @return   */  public int addUser(User user){    ResultSet rs =bookdao.queryUser(user);    try {      if(rs!=null&&!rs.next()){        boolean b =bookdao.addUser(user);        if(b)return 1;       }    } catch (SQLException e) {      // TODO Auto-generated catch block      e.printStackTrace();      return 3;    }      return 2;  }  /**   * 查询用户所有信息   * @param user   * @return   */  public int queryUser(User user){    ResultSet r = bookdao.queryUser(user);    try {      if(r.next()){        user.setBooks(r.getInt("books"));        System.out.println(user);        return 1;      }        return 2;    } catch (SQLException e) {      // TODO Auto-generated catch block      e.printStackTrace();      return 2;    }  }  /**   * 借书 先检查书是否存在，再检查书籍是否有库存，然后检查是否已结借此书   * 最后以上检查没有错误，就可以借书。 用户持有数量增加，借书信息详解录入，库存更新   *    * 注意事项    * 1 resultset 默认指向数据前一个位置 必须 用 next    * 2 需要加入事务 防止出现错误造成数据表更新不一致   * @param bookname 书名   * @return   */  public String borrowBook(String bookname,User user){    try {      if(!bookdao.queryBook(bookname).next()){        return "借书失败-书籍不存在";}      ResultSet querybookrs = bookdao.queryBook(bookname);      while(querybookrs.next()){        int t = querybookrs.getInt("shengyushuliang");        if(t<1){return "库存不足";}        ResultSet rs =bookdao.queryBorrowinfo(user.getUsername());        if(rs!=null&&!rs.next()){          //加入借阅详细信息          boolean b1 =bookdao.addborrowinfo(user.getUsername(), bookname);          //更新借书数量          ResultSet rs1 = bookdao.queryUser(user);          rs1.next();          user.setBooks(rs1.getInt("books")+1);          bookdao.updateUserbooks(user);          //更新库存          boolean b2 =bookdao.updateBookinfo(bookname, t-1);          //System.out.println(b1+" "+b2);          return b1?(b2?"借书成功":"借书失败"):("借书失败");        }       }      return null;    } catch (SQLException e) {      // TODO Auto-generated catch block      e.printStackTrace();      return "借书失败-其他错误";    }  }  /**还书   * 更新用户持有数，归还书的库存，删除借书信息表中信息   * @param user 更新数据数    * @param bookinfo 更新库存后的数   * @return   */  public int returnBook(User user,String bookname){    boolean b1 = bookdao.deleteBorrowInfo(user.getUsername(),bookname);    boolean b2 = false;    boolean b3 = false;    try {      //更新库存      ResultSet r = bookdao.queryBook(bookname);      if(r.next()){        int i = r.getInt("shengyushuliang");        b2 = bookdao.updateBookinfo(bookname,i+1);      }      //更新持有书数      r = bookdao.queryUser(user);      if(r.next()){        int i = r.getInt("books");        user.setBooks(i-1);        b3 =bookdao.updateUserbooks(user);      }      if(!b1||!b2||!b3){        return 2;      }      return 1;    } catch (SQLException e) {      // TODO Auto-generated catch block      e.printStackTrace();      return 2;    }  }  /**   * 查询用户的借书情况   * @param user 用户   * @return 返回借阅信息   */  public List<BorrowInfo> queryborrowinfo(User user){    ResultSet r =  bookdao.queryBorrowinfo(user.getUsername());    List<BorrowInfo> l = new ArrayList<BorrowInfo>();    try {      while(r!=null&&r.next()){        b = new BorrowInfo();        b.setUsername(r.getString("username"));        b.setBookname(r.getString("bookname"));        b.setBorrowdate(r.getDate("borrowdate"));        b.setReturndate(r.getDate("returndate"));        l.add(b);      }      return l;    } catch (SQLException e) {      e.printStackTrace();      return null;    }  }  /**   * 指定页码   * @param age   */  public void fenyeInfo(int age){    int i =bookdao.queryPageInfo();    System.out.println("总页数："+i);    try {      if(i>0){        ResultSet r = bookdao.querySubBookInfo((age-1)*5);        while(r!=null&&r.next()){          System.out.println("书名"+r.getString("bookname")+"作者"+          r.getString("zuozhe")+"总数"+r.getInt("shuliang")+"剩余数量"+r.getInt("shengyushuliang"));            }      }      } catch (SQLException e) {      e.printStackTrace();    }  }  /**   * 指定上下页   * @param age   */  public void fenyeInfo(String age){  }  /**   * 更新图书信息   * 更新作者，库存，剩余数量，不更新日期，书名（不就是添加了新的书籍了吗）   * 可更新任务可以多选   *    * 书名进行判断是否存在   * 库存和剩余数量进行逻辑上的验证   */  public void updateBookinfo(String bookname){    Scanner scan = new Scanner(System.in);    System.out.println("更新作者输入:1，跳过11");    int i =scan.nextInt();    List<List<String>> list = new ArrayList<List<String>>();    List<String> list1 = null;    if(i==1){      String newbookname = scan.next();      list1 = new ArrayList<String>();      list1.add("zuozhe");      list1.add("'"+newbookname+"'");      list.add(list1);    }    //如果更新了库存，剩余数量也会跟着更新 需要判断库存逻辑的正确性    System.out.println("更新数量输入2，跳过22");    int ii = scan.nextInt();    if(ii==2){      System.out.println("请更新库存数量");      int newsum = scan.nextInt();      //判断数量逻辑的正确性      ResultSet r = queryBookK(bookname);      int oldsum=0;int sykc=0;//旧库存和剩余数量      try {        while(r.next()){          oldsum = r.getInt("shuliang");          sykc = r.getInt("shengyushuliang");        }        if(newsum>oldsum){          sykc+=newsum-oldsum;//记录更新后的剩余数量          //System.out.println("根据已有库存，库存总量为---"+newsum);        }        else if(newsum<oldsum&&newsum>=sykc){//如何新的库存少于就库存。判断新库存与剩余数量的关系          sykc-=newsum;        }else{          System.out.println("输入错误");          return ;        }      } catch (SQLException e) {        // TODO Auto-generated catch block        e.printStackTrace();      }      list1 = new ArrayList<String>();      list1.add("shuliang");      list1.add(String.valueOf(newsum));      list.add(list1);      list1 = new ArrayList<String>();      list1.add("shengyushuliang");      list1.add(String.valueOf(sykc));      list.add(list1);    }    bookdao.updateBookinfo(list, bookname);  }}

package library.view;import java.sql.ResultSet;import java.sql.SQLException;import java.util.ArrayList;import java.util.Date;import java.util.InputMismatchException;import java.util.List;import java.util.Scanner;import library.controller.BookController;import library.po.Bookinfo;import library.po.BorrowInfo;import library.po.User;/** * 视图类，也是界面的显示层。程序运行的入口 * 想说的话： * 如果使用web作为v层，只需要把bookrun方法拆开就可以了。对应会话跟踪，把 private static User user 存入session对象就可以了 * 框架的话用springmvc 。对于dao加入orm框架（hibernate ，mybatis）。整合起来也就是常见的ssm体系或ssh体系 * 数据库的选择更是随你心情。mysql SQLserver 等等。 * 项目bug仔细看的话很多。本意想给入门的同学一个思路方向。对于一些变量的命名请不要学我（偷懒），养成一个良好的 * 习惯。祝你在编程的道路上越走越远！！ */public class View {  //controller 业务控制类  private static BookController bookc = new BookController();  //登陆后的用户跟踪类似session  private static User user;  //控制主界面的循环  private static boolean flag = true;  //接受控制台输入  private static Scanner scan = new Scanner(System.in);  public static void main(String[] args) {   bookRun();  }  //主界面  应该考虑其他输入的限定 （当输入字符时，系统停止运行）  public static void bookRun(){      try{        do{          System.out.println("欢迎来到图书借阅系统/n登陆输入: 1/n注册输入: 2/n管理员管理:3");          int i1 = scan.nextInt();          switch (i1) {          case 1://登陆逻辑            System.out.println("输入账号");            String username = scan.next();            System.out.println("密码");            String password = scan.next();            int i =bookc.loginUser(new User(username, password));            if(i==1){              System.out.println("登陆成功");              user = new User(username, password);              loginSuccess(user);            }else if(i!=1){              System.out.println("登陆失败，检查密码或者账号");              }            break;          case 2:            //注册逻辑 可以添加验证密码 进行密码的确定  java api有把明文进行处理的方法，请自行搜索            //还可以加入正则表达式进行账号的限定（对于特殊字符输入的处理等）            System.out.println("输入申请账号");            String username1 = scan.next();            System.out.println("密码");            String password1 = scan.next();            //此处可以再次确认密码的逻辑            System.out.println(addUser(new User(username1, password1)));            System.out.println("返回上一层");            break;          case 3://管理员逻辑            System.out.println("输入管理员账号");            String username2 = scan.next();            System.out.println("密码");            String password2 = scan.next();            user = new User(username2, password2);            int i2 =bookc.loginGuanli(user);            if(i2==1){              loginGuanliSuccess();            }else{              System.out.println("登陆失败，检查密码或者账号");            }            break;          default :            System.out.println("输入序号不正确");            break;          }        }while(flag);      }catch(InputMismatchException e){        System.out.println("输入异常，请重启系统");      }  }  //此处可以添加新的功能而不影响已有功能 （可以改为switch语句）  private static void loginGuanliSuccess() {    while(true){      System.out.println("添加图书：1/n更改图书信息：2/n返回：3");      int i = scan.nextInt();      if(i==1){        addBook();      }else if(i==2){        updateBookinfo();      }else if(i==3){        return;      }    }  }//更新图书/** * 更新图书 只有管理员权限可以操作 */  private static void updateBookinfo() {    //应该判断书名是否存在 contro层设计    System.out.println("请输入书名");    String bookname = scan.next();    int a = bookc.queryBook(bookname);    if(a!=1){      System.out.println("不存在，已返回上一层");      return;    }/*   System.out.println("更新作者输入1，跳过11");    int i =scan.nextInt();    List<List<String>> list = new ArrayList<List<String>>();    List<String> list1 = null;    if(i==1){      String newbookname = scan.next();      list1 = new ArrayList<String>();      list1.add("zuozhe");      list1.add("'"+newbookname+"'");      list.add(list1);    }    //如果更新了库存，剩余数量也会跟着更新 需要判断库存逻辑的正确性    System.out.println("更新数量输入2，跳过22");    int ii = scan.nextInt();    if(ii==2){      //判断数量逻辑的正确性      ResultSet r =bookc.queryBookK(bookname);      try {        int i1=0;int i2=0;        while(r.next()){          i1 = r.getInt("shuliang");          i2 = r.getInt("shengyushuliang");        }        if(ii>i1){          i2+=ii-i1;        }        if(ii<i1&&ii>=i2){        }        System.out.println("更新后的数量错误");        return;      } catch (SQLException e) {        // TODO Auto-generated catch block        e.printStackTrace();      }      String newkucun= scan.next();      list1 = new ArrayList<String>();      list1.add("shuliang");      list1.add(newkucun);      list.add(list1);    }*/    bookc.updateBookinfo(bookname);  }//添加图书 需要保证名字唯一性  private static void addBook() {    System.out.println("图名");    String bookname = scan.next();    System.out.println("作者");    String zuozhe = scan.next();    System.out.println("数量");    int  shuliang = scan.nextInt();    Bookinfo bookinfo = new Bookinfo(bookname, zuozhe, shuliang, shuliang,new Date());    int i =bookc.addBookinfo(bookinfo);    if(i==1){      System.out.println("添加成功");    }else{      System.out.println("错误");    }  }  //注册界面的实现  private static String addUser(User user){    switch (bookc.addUser(user)) {    case 1:      return "注册成功";    case 2:      return "用户已注册";    case 3:      return "其他错误，重试";    }    return "其他错误，重试";  }  //登陆功能实现  private static void loginSuccess(User user ){    while (true){      System.out.println("查看借阅信息请输入：1，借书：2，还书：3，账号信息：4,退出：5"          + "查询图书：6修改密码：7/n");      int i = scan.nextInt();      switch (i) {      case 1:        borrowInfo(user);        break;      case 2:        borrowBook(user);        break;      case 3:        returnBook(user);        break;      case 4:        queryUser(user);        break;      case 5:        return ;      case 6:        System.out.println("请输入书名");        queryBook(scan.next());        break;      case 7: break;      default:        System.out.println("输入错误");        break;      }    }  }  //查询借阅信息  private static void borrowInfo(User user ){    List<BorrowInfo> l=bookc.queryborrowinfo(user);    if(l==null||l.isEmpty()){      System.out.println("没有借阅信息");      return;    }    for (BorrowInfo borrowInfo : l) {      System.out.println(borrowInfo);    }  }  //借书  private static void borrowBook(User user){    System.out.println("请输入借阅的书籍名称");    String bookname =scan.next();    String flog = bookc.borrowBook(bookname, user);    System.out.println(flog);    System.out.println("是否继续借书：y|n");    String flog1 = scan.next();    if(flog1.equalsIgnoreCase("y")){      borrowBook(user);    }  }  //还书  private static void returnBook(User user1 ){    List<BorrowInfo> l=bookc.queryborrowinfo(user1);    if(l==null||l.isEmpty()){      System.out.println("没有借阅信息");      return;    }    for (BorrowInfo borrowInfo : l) {      System.out.println(borrowInfo);    }    System.out.println("请输入要还书籍的名字");    String bookname = scan.next();    int flog =bookc.returnBook(user1, bookname);    if(flog==1){      System.out.println("还书成功");    }else{      System.out.println("失败");    }    System.out.println("是否继续还书：y|n");    String flog1 = scan.next();    if(flog1.equalsIgnoreCase("y")){      returnBook(user1);    }    }  //用户信息  private static void queryUser(User user){    int i =bookc.queryUser(user);    if( i!=1){      System.out.println("失败");    }  }  private static void queryBook(String bookname){    int i = bookc.queryBook(bookname);    if(i!=1)System.out.println("书籍不存在");  }  private static void GuanliFace(){    while(true){      System.out.println("查询书籍列表请输入 ：1；添加图书：2；使用分页查看书籍列表");      int i =scan.nextInt();      switch (i) {      case 1:        int i1= bookc.queryBookinfo();        if(i1==2)System.out.println("错误");        break;      case 2:        System.out.println("书名");        String booknname1 = scan.next();        System.out.println("作者");        String zuozhe1 = scan.next();        System.out.println("数量");        int shuliang1 = scan.nextInt();        Date date = new Date();        int i3 = bookc.addBookinfo(new Bookinfo(booknname1, zuozhe1, shuliang1, shuliang1, date));        if(i3==2)System.out.println("错误");        break;      case 3:      default:        System.out.println("错");        break;      }    }  }  private static void fenyeInfo(){  }}

/用户表CREATE TABLE `userinfo` ( `id` int(10) NOT NULL AUTO_INCREMENT, `username` varchar(20) COLLATE utf8_bin DEFAULT NULL, `password` varchar(20) COLLATE utf8_bin DEFAULT NULL, `books` int(10) DEFAULT NULL, `isguanli` int(10) NOT NULL DEFAULT '0', PRIMARY KEY (`id`)) ENGINE=InnoDB AUTO_INCREMENT=21 DEFAULT CHARSET=utf8 COLLATE=utf8_bin;/借书信息CREATE TABLE `borrowinfo` ( `id` int(10) NOT NULL AUTO_INCREMENT, `username` varchar(20) COLLATE utf8_unicode_ci DEFAULT NULL, `bookname` varchar(20) COLLATE utf8_unicode_ci DEFAULT NULL, `borrowdate` date DEFAULT NULL, `returndate` date DEFAULT NULL, PRIMARY KEY (`id`)) ENGINE=InnoDB AUTO_INCREMENT=9 DEFAULT CHARSET=utf8 COLLATE=utf8_unicode_ci;/书籍信息 字段用的拼音:-DCREATE TABLE `bookinfo` ( `id` int(10) NOT NULL AUTO_INCREMENT, `bookname` varchar(20) COLLATE utf8_unicode_ci NOT NULL, `zuozhe` varchar(20) COLLATE utf8_unicode_ci DEFAULT NULL, `shuliang` varchar(20) COLLATE utf8_unicode_ci DEFAULT NULL, `shengyushuliang` varchar(20) COLLATE utf8_unicode_ci DEFAULT NULL, `date` date DEFAULT NULL, PRIMARY KEY (`id`)) ENGINE=InnoDB AUTO_INCREMENT=13 DEFAULT CHARSET=utf8 COLLATE=utf8_unicode_ci;