如何将凭据传递给我的数据库连接类？

db.host=数据库主机名
db.port=数据库端口
db.username=数据库用户名
db.password=数据库密码

import java.io.FileInputStream;
import java.io.IOException;
import java.util.Properties;

public class DatabaseConnection {
    private String host;
    private int port;
    private String username;
    private String password;

    public DatabaseConnection() {
        Properties properties = new Properties();
        try {
            properties.load(new FileInputStream("config.properties"));
            host = properties.getProperty("db.host");
            port = Integer.parseInt(properties.getProperty("db.port"));
            username = properties.getProperty("db.username");
            password = properties.getProperty("db.password");
        } catch (IOException e) {
            e.printStackTrace();
        }
    }

    public void connect() {
        // 使用获取到的凭据建立数据库连接
        // 示例中使用MySQL的JDBC驱动程序
        String url = "jdbc:mysql://" + host + ":" + port + "/database_name";
        try {
            Connection connection = DriverManager.getConnection(url, username, password);
            // 进行数据库操作
        } catch (SQLException e) {
            e.printStackTrace();
        }
    }
}