图书管理

这是一个简单的图书管理系统，对部分功能的进行了实现，主要就是练习对数据库的增删改查和逻辑的运用！

1、使用的Oracle数据库，先建数据库，并插入几条简单的数据

2、在MyEclipse中建立Web Project，命名为bookManager，建包结构如下

3、首先写dao包中的IBaseDao,然后用OracleBaseDao实现方法连接数据库（getConnection）和关闭连接（closeCon）,代码如下 

package cn.dao.utils.impl;

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;

import cn.dao.utils.interfaces.IBaseDao;

/**
 * 使用Oracle数据库
 *
 * @author CCQ
 *
 */
public class oracleBaseDao implements IBaseDao {

    static String DRIVER_CLASS = "oracle.jdbc.driver.OracleDriver";
    static String URL = "jdbc:oracle:thin:@localhost:1521:orcl";
    static String USER = "hope";
    static String PWD = "123456";

    @Override
    public Connection getConn() throws Exception {
        // TODO Auto-generated method stub
        Connection conn = null;
        try {
            Class.forName(DRIVER_CLASS);
            conn = DriverManager.getConnection(URL, USER, PWD);
        } catch (Exception e) {
            throw new Exception(e.getMessage());
        }
        return conn;
    }

    @Override
    public void closeConn(ResultSet rs, PreparedStatement ps, Connection conn)
            throws Exception {
        // TODO Auto-generated method stub
        try {
            if (rs != null) {
                rs.close();
            }
            if (ps != null) {
                ps.close();
            }
            if (conn != null) {
                conn.close();
            }
        } catch (Exception e) {
            throw new Exception(e.getMessage());
        }
    }
}

4、书写dao包中的UserDaoImpl，实现用户登录，再写bookDaoImpl，实现对图书的操作，代码如下

package cn.dao.impl;

import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;

import cn.dao.interfaces.IUserDao;
import cn.dao.utils.impl.oracleBaseDao;
import cn.dao.utils.interfaces.IBaseDao;
import cn.po.User;
/**
 * 用户操作实现类
 * @author CCQ
 *
 */
public class UserDaoImpl implements IUserDao {
    IBaseDao baseDao = new oracleBaseDao();

    @Override
    public User login(User user) throws Exception {
        // TODO Auto-generated method stub
        User users = null;
        try {
            Connection conn = baseDao.getConn();
            String sql = "select * from users where username = ? and userpwd = ?";
            PreparedStatement ps = conn.prepareStatement(sql);
            ps.setObject(1, user.getUserName());
            ps.setObject(2, user.getUserPwd());
            ResultSet rs = ps.executeQuery();
            if(rs.next()){
                users = new User();
                users.setUserId(rs.getInt("userId"));
                users.setUserName(rs.getString("userName"));
                users.setUserPwd(rs.getString("userPwd"));
            }
            baseDao.closeConn(rs, ps, conn);
        } catch (Exception e) {
            throw new Exception(e);
        }
        return users;
    }

}

package cn.dao.impl;

import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.util.ArrayList;
import java.util.List;

import cn.dao.interfaces.IBookDao;
import cn.dao.utils.impl.oracleBaseDao;
import cn.dao.utils.interfaces.IBaseDao;
import cn.po.Book;

/**
 * 对图书操作的实现类
 *
 * @author CCQ
 *
 */
public class BookDaoImpl implements IBookDao {
    IBaseDao baseDao = new oracleBaseDao();
    private Connection conn = null;
    private PreparedStatement ps = null;
    private ResultSet rs = null;
    int r = 0;

    @Override
    public List<Book> findBooks() throws Exception {
        // TODO Auto-generated method stub
        List<Book> books = new ArrayList<Book>();
        try {
            conn = baseDao.getConn();
            String sql = "select * from books order by bookid";
            ps = conn.prepareStatement(sql);
            rs = ps.executeQuery();
            while (rs.next()) {
                Book book = new Book();
                book.setBookId(rs.getInt("bookId"));
                book.setBookName(rs.getString("bookName"));
                book.setBookAutor(rs.getString("bookAutor"));
                book.setBookType(rs.getString("bookType"));
                book.setBookPrice(rs.getDouble("bookPrice"));
                books.add(book);
            }
            baseDao.closeConn(rs, ps, conn);
        } catch (Exception e) {
            throw new Exception(e);
        }
        return books;
    }

    @Override
    public int addBook(Book book) throws Exception {
        // TODO Auto-generated method stub
        try {
            conn = baseDao.getConn();
            String sql = "insert into books values(?,?,?,?,?)";
            ps = conn.prepareStatement(sql);
            ps.setObject(1, book.getBookId());
            ps.setObject(2, book.getBookName());
            ps.setObject(3, book.getBookAutor());
            ps.setObject(4, book.getBookType());
            ps.setObject(5, book.getBookPrice());
            r = ps.executeUpdate();
            baseDao.closeConn(rs, ps, conn);
        } catch (Exception e) {
            throw new Exception(e);
        }
        return r;
    }

    @Override
    public Book findBookByBookName(String bookName) throws Exception {
        // TODO Auto-generated method stub
        Book book = null;
        try {
            conn = baseDao.getConn();
            String sql = "select * from books where bookname = ?";
            ps = conn.prepareStatement(sql);
            ps.setObject(1, bookName);
            rs = ps.executeQuery();
            if (rs.next()) {
                book = new Book();
                book.setBookId(rs.getInt("bookId"));
                book.setBookName(rs.getString("bookName"));
                book.setBookAutor(rs.getString("bookAutor"));
                book.setBookType(rs.getString("bookType"));
                book.setBookPrice(rs.getDouble("bookPrice"));
            }
            baseDao.closeConn(rs, ps, conn);
        } catch (Exception e) {
            throw new Exception(e);
        }
        return book;
    }

    @Override
    public int deleteBook(String bookName) throws Exception {
        // TODO Auto-generated method stub
        try {
            conn = baseDao.getConn();
            String sql = "delete books where bookname = ?";
            ps = conn.prepareStatement(sql);
            ps.setObject(1, bookName);
            r = ps.executeUpdate();
            baseDao.closeConn(rs, ps, conn);
        } catch (Exception e) {
            throw new Exception(e);
        }
        return r;
    }

    @Override
    public int modifyBook(Book book) throws Exception {
        // TODO Auto-generated method stub
        try {
            conn = baseDao.getConn();
            String sql = "update books set bookname = ?,bookautor = ?,booktype = ?,bookprice = ? where bookid = ?";
            ps = conn.prepareStatement(sql);
            ps.setObject(1, book.getBookName());
            ps.setObject(2, book.getBookAutor());
            ps.setObject(3, book.getBookType());
            ps.setObject(4, book.getBookPrice());
            ps.setObject(5, book.getBookId());
            r = ps.executeUpdate();
            baseDao.closeConn(rs, ps, conn);
        } catch (Exception e) {
            throw new Exception(e);
        }
        return r;
    }
}

5、书写services包，中的接口类，和实现类，也就是调用相应的dao包的中方法(简单)。

6、书写一个BookManagerSys类来通过控制台输入验证功能是否正确，代码如下：

package cn.test;

import java.util.ArrayList;
import java.util.List;
import java.util.Scanner;

import cn.po.Book;
import cn.po.User;
import cn.services.impl.BookServiceImpl;
import cn.services.impl.UserServiceImpl;
import cn.services.interfaces.IBookService;
import cn.services.interfaces.IUserService;

/**
 * 图书管理系统界面
 *
 * @author CCQ
 *
 */
public class BookManagerSys {

    IUserService userService = new UserServiceImpl();
    IBookService bookService = new BookServiceImpl();
    Scanner input = new Scanner(System.in);

    public void menu() throws Exception {
        User user = new User();
        System.out.println("
	图书管理系统登录界面");
        System.out.print("用户名：");
        user.setUserName(input.next());
        System.out.print("密    码：");
        user.setUserPwd(input.next());
        user = userService.login(user);
        if (user != null) {
            bmenu();
        } else {
            System.out.println("用户名或密码错误，请重新输入！");
            menu();
        }
    }

    public void bmenu() throws Exception {
        System.out.println("
	图书管理系统主界面");
        System.out.println("1.添加图书");
        System.out.println("2.查看所有图书信息");
        System.out.println("3.删除图书");
        System.out.println("4.修改图书信息");
        System.out.println("5.退出系统");
        System.out.print("请选择(1-5)：");
        int op = input.nextInt();
        switch (op) {
        case 1:
            addBook();
            break;
        case 2:
            findBooks();
            break;
        case 3:
            deleteBook();
            break;
        case 4:
            modifyBook();
            break;
        case 5:
            System.out.println("谢谢使用图书管理系统！");
            System.exit(0);
        default:
            System.out.println("输入错误，请输入1-5数字");
        }

    }

    public void addBook() throws Exception {
        Book book = new Book();
        System.out.println("
	图书信息添加界面");
        System.out.print("图书编号：");
        book.setBookId(input.nextInt());
        System.out.print("图书名称：");
        book.setBookName(input.next());
        if (bookService.findBookByBookName(book.getBookName()) == null) {
            System.out.print("图书作者：");
            book.setBookAutor(input.next());
            System.out.print("图书类别：");
            book.setBookType(input.next());
            System.out.print("图书价格：");
            book.setBookPrice(input.nextDouble());
            int r = bookService.addBook(book);
            if (r != 0) {
                System.out.println(book.getBookName() + "添加成功！");
                bmenu();
            }
        } else {
            System.out.println(book.getBookName() + "已经存在，不可重复添加！");
            addBook();
        }

    }

    public void findBooks() throws Exception {
        System.out.println("
		查看所有图书信息界面");
        System.out.println("图书编号	图书名称	作者	类别	图书价格");
        List<Book> books = new ArrayList<Book>();
        books = bookService.findBooks();
        for (Book book : books) {
            System.out.println(book.getBookId() + "	" + book.getBookName()
                    + "	" + book.getBookAutor() + "	" + book.getBookType()
                    + "	" + book.getBookPrice());
        }
        bmenu();
    }

    public void deleteBook() throws Exception {
        System.out.println("
		删除图书信息界面");
        System.out.print("请输入删除图书名称：");
        String bookName = input.next();
        if (bookService.findBookByBookName(bookName) != null) {
            int r = bookService.deleteBook(bookName);
            if(r != 0){
                System.out.println("删除"+bookName+"成功！");
                bmenu();
            }
        } else {
            System.out.println("您输入的"+bookName+"不存在！");
            bmenu();
        }
    }

    public void modifyBook() throws Exception {
        Book book = new Book();
        System.out.println("
		修改图书信息界面");
        System.out.print("请输入修改的图书名称：");
        book.setBookName(input.next());
        if (bookService.findBookByBookName(book.getBookName()) != null) {
            book.setBookId(bookService.findBookByBookName(book.getBookName()).getBookId());
            System.out.print("请输入修改的图书作者：");
            book.setBookAutor(input.next());
            System.out.print("请输入修改的图书类别：");
            book.setBookType(input.next());
            System.out.print("请输入修改的图书价格：");
            book.setBookPrice(input.nextDouble());
            int r = bookService.modifyBook(book);
            if(r != 0){
                System.out.println("修改"+book.getBookName()+"成功！");
                bmenu();
            }else{
                System.out.println("修改失败！");
            }

        } else {
            System.out.println("您输入的"+book.getBookName()+"不存在！");
            bmenu();
        }
    }

}

7、结果展示：

8、总结：

经过这一个星期的学习，具体把Java中的面对对象的思想进行了深刻的掌握，然后学习Oracle中的简单建表和一些简单地SQL的增删改查！感觉掌握的还是不错的，Oracle数据库用着还是比较的顺手，感觉很好用，下阶段我要继续加油哦！加油！加油！加油！重要的事情说三遍！