sql怎样连接到数据库服务器配置

<?php
$servername = "localhost";
$username = "root";
$password = "password";
$dbname = "mydatabase";

// 创建连接
$conn = new mysqli($servername, $username, $password, $dbname);

// 检测连接是否成功
if ($conn->connect_error) {
    die("连接失败: " . $conn->connect_error);
}
echo "连接成功";
?>

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

public class Main {
    public static void main(String[] args) {
        String url = "jdbc:oracle:thin:@localhost:1521:xe";
        String username = "username";
        String password = "password";

        try {
            // 加载驱动程序
            Class.forName("oracle.jdbc.driver.OracleDriver");
            // 创建连接
            Connection conn = DriverManager.getConnection(url, username, password);
            System.out.println("连接成功");
        } catch (ClassNotFoundException e) {
            e.printStackTrace();
        } catch (SQLException e) {
            e.printStackTrace();
        }
    }
}