Eclipse连接Mysql成功，然后进行增删改查操作

package Sqldata;

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.SQLException;

import com.mysql.jdbc.PreparedStatement;

public class SqlMain {

    public static void main(String[] args) throws ClassNotFoundException, SQLException {
        // TODO Auto-generated method stub
//       连接Mysql
//        加载驱动
        Class.forName("com.mysql.jdbc.Driver");
//        填写url 用户 密码获得连接
        Connection  connection=DriverManager.getConnection("jdbc:mysql://127.0.0.1:3306/book?useUnicode=true&characterEncoding=utf-8","root","root123");
        System.out.println(connection);
        
//        插入
//        构造sql语句
        String  sql="insert into user_table values(?,?,?,?,?,?)";
//        获得执行sql的对象（根据connection获得）
        PreparedStatement statement=(PreparedStatement) connection.prepareStatement(sql);
//        往sql里赋值
        statement.setInt(1, 4);
        statement.setString(2, "美羊羊");
        statement.setInt(3, 21);
        statement.setString(4, "女");
        statement.setString(5, "123412341234");
        statement.setString(6, "110110");
        int a=statement.executeUpdate();
        System.out.println(a);
//        删除
      String sql1="delete from user_table where user_id=?";
      PreparedStatement statement1 =(PreparedStatement) connection.prepareStatement(sql1);
        statement.setInt(1, 4);
        statement.executeUpdate();
//        修改
        String sql2="update user_table set user_name=? ,user_age=? where user_id=?";
        PreparedStatement statement2 =(PreparedStatement) connection.prepareStatement(sql2);
        statement.setString(1, "懒洋洋");
        
        statement.setInt(2, 12);
        statement.setInt(3, 2);
        statement.executeUpdate();
        
        
    }

}