六、使用JDBC访问MySQL

6.1、下载驱动

6.2、JDBC访问MySQL

示例一：

package jdbctest;

import java.math.BigDecimal;
import java.sql.*;
import java.util.Scanner;

public class GoodsDao {

    static {
        try {
            /*加载驱动*/
            Class.forName("com.mysql.jdbc.Driver");
        } catch (ClassNotFoundException e) {
            e.printStackTrace();
        }
    }

    public static void main(String[] args) {
        /**添加*/
        insert();
        /**查询*/
        select();
    }

    /**查询*/
    private static void select() {
        try {
            /**获得连接对象*/
            Connection conn = DriverManager.getConnection("jdbc:mysql://localhost:3306/nfmall?useUnicode=true&characterEncoding=UTF-8", "root", "123");

            /**创建sql命令对象*/
            PreparedStatement statement=conn.prepareStatement("SELECT goods.id, goods.title, goods.category_id, goods.add_date, goods.picture, goods.state, goods.details, goods.price, category.`name`, category.parentId FROM goods INNER JOIN category ON goods.category_id = category.id where price>=?");
            //设置参数
            statement.setInt(1,1000);
            //执行并获得结果集
            ResultSet result=statement.executeQuery();
            //遍历结果集
            while (result.next()){
                //在当前行根据列名获得数据
                String title=result .getString("title");
                BigDecimal price=result.getBigDecimal("price");
                System.out.println(title+"\t"+price);
            }

            //关闭
            result.close();
            statement.close();
            conn.close();
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

    /**添加*/
    private static void insert() {
        try {
            //输入用的扫描器
            Scanner input=new Scanner(System.in);

            /**获得连接对象*/
            Connection conn = DriverManager.getConnection("jdbc:mysql://localhost:3306/nfmall?useUnicode=true&characterEncoding=UTF-8", "root", "123");

            /**创建sql命令对象*/
            PreparedStatement statement=conn.prepareStatement("insert into goods(title,category_id,picture,price,details,state) VALUES(?,?,?,?,?,default);");

            System.out.print("名称：");
            String title=input.next();
            System.out.print("类型：");
            int cateId=input.nextInt();
            System.out.print("图片：");
            String picture=input.next();
            System.out.print("价格：");
            BigDecimal price=input.nextBigDecimal();
            System.out.print("详细：");
            String details=input.next();

            //设置参数
            statement.setString(1,title);
            statement.setInt(2,cateId);
            statement.setString(3,picture);
            statement.setBigDecimal(4,price);
            statement.setString(5,details);

            //执行并获得影响行数
            int rows=statement.executeUpdate();

            System.out.println("执行："+(rows>0?"成功":"失败"));

            //关闭
            statement.close();
            conn.close();
        } catch (Exception e) {
            e.printStackTrace();
        }
    }


}

结果：