JAVA-jdbc-preparestatement接口-预编译sql

package cn.bruce.MySql;

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

public class Prepared {
    public static void main(String[] args) {
        String name, password, url, sql, jdbc;
        Connection con = null;
        name = "root";
        password = "jinqi1986";
        url = "jdbc:mysql://localhost:3306/mytrain?useSSL=false&serverTimezone=CTT";
        jdbc = "com.mysql.cj.jdbc.Driver";
        try
        {
            Class.forName(jdbc);
            System.out.println("驱动加载成功");
        } catch (Exception e)
        {
            e.printStackTrace();
        }
        try
        {
            con = DriverManager.getConnection(url, name, password);
            System.out.println("连接成功");
        } catch (Exception e)
        {
            e.printStackTrace();
        }
        try
        {
            String n = "小金11";
            String p = "12345622";
            sql = "update  users set zusename = ?, zpassword = ? where id = ?;";
            PreparedStatement ps = con.prepareStatement(sql);
            ps.setString(1, n);
            ps.setString(2, p);
            ps.setInt(3, 2);
            System.out.println(ps.executeUpdate() + "行进行修改");
        } catch (Exception e)
        {
            e.printStackTrace();
        }
        try
        {
            String n = "小金22";
            String p = "334455";
            String n1 = "小金33";
            String p1 = "22334455";
            sql = "insert into  users (zusename,zpassword) values (?,?),(?,?);";
            PreparedStatement ps = con.prepareStatement(sql);
            ps.setString(1, n);
            ps.setString(2, p);
            ps.setString(3, n1);
            ps.setString(4, p1);
            System.out.println(ps.executeUpdate() + "行进行修改");
        } catch (Exception e)
        {
            e.printStackTrace();
        }
        try
        {
            sql = "select * from users;";
            PreparedStatement ps = con.prepareStatement(sql);
            ResultSet rs = ps.executeQuery();
            while (rs.next())
            {
                System.out.println(
                        rs.getString("id") + "  " + rs.getString("zusename") + "  " + rs.getString("zpassword"));
            }
            ps.close();
        } catch (Exception e)
        {
            e.printStackTrace();
        } finally
        {
            try
            {
                con.close();

            } catch (Exception e2)
            {
                e2.printStackTrace();
            }
        }
    }
}