How can I validate required input fields using Selenium
<p>I'm new in automation testing and have a task to implement the automation to Register Student using a given Registration Form. </p>

<p>The scenario is letting me a little bit confused on how to validate the input field in the registration form. </p>

<p>I mean, if I don't fill a required field, the browser will indicate that I must fill that field. </p>

<p>Another thing is that I'm using a <code>for loop</code> for 2 students, where I want the first time to leave the input fields empty. After submit I have to see it was validated and then fill the empty input fields to submit it again (now with data inserted in the fields).</p>

<p>I'm sharing my code and would appreciate any help.</p>

<pre><code>public class Cartus {

    public static  void fill() throws InterruptedException {

        System.setProperty("webdriver.chrome.driver", "E:\\workspace\\chromeDriver\\chromeDriver.exe");

        ChromeDriver driver = new ChromeDriver();

        for(int i=0; i&lt;2; i++) {

            driver.get("http://qa-5.ls.vu/v2/landing-page/cartus/en");
            driver.findElement(By.xpath("/html/body/div[4]/div/form/div[1]/div")).click();
            driver.findElement(By.xpath("/html/body/div[4]/div/form/div[1]/div/select/option[2]")).click();
            driver.findElement(By.xpath("/html/body/div[4]/div/form/div[2]/div[1]/input")).sendKeys(/*"sami"*/);
            driver.findElement(By.xpath("/html/body/div[4]/div/form/div[2]/div[2]/input")).sendKeys(/*"Mohaname"*/);

            WebElement ele=driver.findElement(By.xpath("/html/body/div[4]/div/form/div[3]/div[1]/input"));/*.sendKeys("0221-1234567");*/

            String date = FastDateFormat.getInstance("yyyyMMddHHmmss").format(System.currentTimeMillis());
            Thread.sleep(1000);
            driver.findElement(By.xpath("/html/body/div[4]/div/form/div[3]/div[2]/input"))
                    .sendKeys(/*"aali_"+date+"@outlook.com"*/);
            driver.findElement(By.id("submitButton")).click();

            if(ele.getAttribute("value").isEmpty()){
                driver.findElement(By.xpath("/html/body/div[4]/div/form/div[2]/div[1]/input")).sendKeys("abcds");
            }
            if(ele.getAttribute("value").isEmpty()){
                driver.findElement(By.xpath("/html/body/div[4]/div/form/div[2]/div[2]/input")).sendKeys("abcds");
            }
            if(ele.getAttribute("value").isEmpty()){
                driver.findElement(By.xpath("/html/body/div[4]/div/form/div[3]/div[1]/input")).sendKeys("abcds");
            }
            if(ele.getAttribute("value").isEmpty()){
                driver.findElement(By.xpath("/html/body/div[4]/div/form/div[3]/div[2]/input")).sendKeys("aali_"+date+"@outlook.com");
            }       
            System.out.println("Test case succesfully run");
        }
    }
}
</code></pre>

<p>Thank you.</p>