Java优学网URL类入门解析：从基础创建到实战预加载，轻松掌握网络编程核心技巧

URL courseUrl = new URL("https://www.uxuewang.com/courses");

URL url = new URL("https://www.uxuewang.com/courses"); String protocol = url.getProtocol(); // 返回 "https"

public void preloadThumbnails(List videoIds) {

for (String videoId : videoIds) {
    try {
        URL thumbUrl = new URL(CDN_BASE + "/thumbs/" + videoId + ".jpg");
        URLConnection conn = thumbUrl.openConnection();
        conn.setConnectTimeout(2000);
        conn.connect(); // 建立连接但不读取数据
    } catch (IOException e) {
        // 静默处理，预加载失败不影响主流程
    }
}

}