JDBC连接数据库实现——手把手教你打造一款简单的图书管理系统

public class Book {
    //定义图书的编号、名称、出版社、价格
    private String id,name,press;
    private double price;
    //构造方法
    public Book(String id, String name, String press, double price) {
        this.id = id;
        this.name = name;
        this.press = press;
        this.price = price;
}
    public String getId() {
        return id;
}
    public void setId(String id) {
        this.id = id;
}
    public String getName() {
        return name;
}
    public void setName(String name) {
        this.name = name;
}
    public String getPress() {
        return press;
}
    public void setPress(String press) {
        this.press = press;
}
    public double getPrice() {
        return price;
}
    public void setPrice(double price) {
        this.price = price;
  }
}

import java.sql.*;
import java.util.Scanner;
public class BookManager {
    //定义com.mysql.jdbc的Driver类路径、数据库的地址、用户名、密码
    static String driver ="com.mysql.jdbc.Driver";
    static String url="jdbc:mysql://localhost:3306/book?useUnicode=true&characterEncoding=utf-8";
    static String user="root";
    static String pwd="168168";
    //创建Connection、Statement、ResultSet对象
    static Connection con;
    static Statement stmt;
    static ResultSet rs;
    public static void main(String[] args) {
        BookManager bm=new BookManager();
        try {
            Class.forName(driver);//加载驱动程序
            System.out.println("加载驱动成功！");
            con=DriverManager.getConnection(url,user,pwd);
            stmt=con.createStatement();
        } catch (ClassNotFoundException e) {
            e.printStackTrace();
        } catch (SQLException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
        //模块化
        System.out.println("1---插入图书");
        System.out.println("2---删除图书");
        System.out.println("3---更新图书信息");
        System.out.println("4---查询图书信息");
        System.out.println("请输入你的选择1~4：");
        Scanner sc=new Scanner(System.in);
        int i=sc.nextInt();
        switch(i){
        case 1:
            insertBook();break;
        case 2:
            deleteBook();break;
        case 3:
            updateBook();break;
        case 4:
            queryBook();break;
        default:
            System.out.println("您的输入有误！");
        }
}
    private static void queryBook(){//查询
        String sql="select * from book";
        try {
            rs=stmt.executeQuery(sql);
            while(rs.next()){
                System.out.println(rs.getString("id"));
                System.out.println(rs.getString("name"));
                System.out.println(rs.getString("press"));
                System.out.println(rs.getDouble("price"));
            }
        } catch (SQLException e) {
            e.printStackTrace();
        }
}
    private static void updateBook(){//修改
        System.out.println("请输入图书Id：");
        Scanner sc=new Scanner(System.in);
        String oldid=sc.next();
        System.out.println("请输入您要更新图书Id：");
        String newid=sc.next();
        String sql="update book set id='"+newid+"' where id='"+oldid+"'";
        try {
            stmt.executeUpdate(sql);
        } catch (SQLException e) {
            e.printStackTrace();
        }
        System.out.println(sql);
}
    private static void deleteBook(){//删除
        System.out.println("请输入您要删除的图书Id：");
        Scanner sc=new Scanner(System.in);
        String id=sc.next();
        String sql="delete from book where id='"+id+"'";
        System.out.println(sql);
        try {
            stmt.executeUpdate(sql);
        } catch (SQLException e) {
            e.printStackTrace();
        }
}
    private static void insertBook(){//插入
        Scanner sc=new Scanner(System.in);
        System.out.println("请输入您要添加的图书id：");
        String id=sc.next();
        System.out.println("请输入您要添加的图书name：");
        String name=sc.next();
        System.out.println("请输入您要添加的图书press：");
        String press=sc.next();
        System.out.println("请输入您要添加的图书price：");
        String price=sc.next();
        try {
            Book b=new Book(id,name,press,Integer.valueOf(price));
            String sql="insert into book values('"+b.getId()+"','"+b.getName()+"','"+b.getPress()+"',"+b.getPrice()+")";
            System.out.println(sql);
            stmt.executeUpdate(sql);
        } catch (SQLException e) {
            e.printStackTrace();
        }
    }
}