Java 从web服务器（.txt文件）读取重定向文件并验证来自页面的响应（“MalformedURLException:无协议”）

第一次发帖，但是我使用这个网站的次数已经超过了我的记忆！我对编程非常陌生，我的任务是用SeleniumWebDriver编写自动化测试脚本，这最终使我学会了一些Java的基本知识

我试图做的是读取一个文本文件，一个驻留在web服务器上的大型重定向文件，遍历每一行，最后检查我还没有真正编码的页面的响应。我已经创建了一个脚本，加载每个页面并断言它不是404，但我正在寻找一个解决方案，希望通过测试http响应可以更快

文本文件中的行可能以以下格式显示：

myredirect//主机外部的url

anotherredirect/apage.html//重定向和目标路径之间只有一个空格，没有协议/主机

andanotherredirect/apage.html//重定向和目标路径之间有两个空格，同样没有协议/主机

我遇到了以下失败：

java.net.MalformedURLException:无协议：

我感谢任何帮助

public class RedirectTestFireFox {
WebDriver driver;
StringBuffer verificationErrors = new StringBuffer();


@Before
public void setUp() throws Exception {

    driver = new FirefoxDriver();
    driver.manage().timeouts().implicitlyWait(30, TimeUnit.SECONDS);
}

@Test
public void testRedirectTestFireFox() throws InterruptedException, IOException {

    //read redirects from file on web server
    URL test = new URL("https://www.example.com/redirects.txt");

    //get the protocol (http or https)
    String protocol = test.getProtocol();

    //get the host of the supplied url
    String host = test.getHost();

    //create baseURL variable that appends protocol "://" and the host
    String baseURL= protocol + "://" + host;

    //do something to each URL in text file
    try (Scanner scan = new Scanner(test.openStream())){
        //while there is still another line in the redirects file...
        while(scan.hasNextLine()) {

            //assign value to "line" variable
            String line = scan.nextLine();

            if(line != null){

                String redirect = line.substring(0, line.indexOf(" "));

                //find the last instance of a space and then take what is to the right of that and assign it back to line variable
                line = line.substring(line.lastIndexOf(" ")+1, line.length());

                //trim off any blank spaces from either end
                line.trim();

                //test to see if the first character starts with "/"
                boolean firstChar = line.startsWith("/");

                //if firstChar is "/" append the baseURL variable to the redirect
                if(firstChar) {
                    line = baseURL + line;
                }

                URL u = new URL(line); //this is the where it fails!!!
                HttpURLConnection urlConnection =(HttpURLConnection) u.openConnection (); 
                urlConnection.setRequestMethod("GET");
                urlConnection.connect();
                try {
                    int code = urlConnection.getResponseCode();
                    assertEquals(200, code);
                } catch (AssertionError e) {
                    System.err.println("Error found! " + redirect);
                }

            }

        }
    }

    }

@After
    public void tearDown() throws Exception {
    driver.close();
}

}

Selenium在这方面绝对是错误的工具。尝试curl、wget、httpbuilder等。