Connection
Statement
DriverManager

public class Demo02 {
    // JDBC执行删除
    public static void main(String[] args) {
        Connection conn = null;
        Statement stmt = null;
        try {
            // 注册驱动
            DriverManager.registerDriver(new com.mysql.jdbc.Driver());
            // 获取连接
            conn = DriverManager.getConnection("jdbc:mysql://localhost:3306/lianxi", "root", "******");
            stmt = conn.createStatement();
            // 执行SQL语句
            String sql = "delete from demo1 where age = 18";
            // 处理查询结果集
            int c = stmt.executeUpdate(sql);
            System.out.println(c == 1 ? "删除成功" : "删除失败");
        } catch (SQLException e) {
            e.printStackTrace();
        } finally {
            // 释放资源
            if (stmt != null) {
                try {
                    stmt.close();
                } catch (SQLException e) {
                    e.printStackTrace();
                }
            }
            if (conn != null) {
                try {
                    stmt.close();
                } catch (SQLException e) {
                    e.printStackTrace();
                }
            }
        }
    }
}