Selenium error handler

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from typing import Any
from typing import Dict
from typing import Type

from selenium.common.exceptions import ElementClickInterceptedException
from selenium.common.exceptions import ElementNotInteractableException
from selenium.common.exceptions import ElementNotSelectableException
from selenium.common.exceptions import ElementNotVisibleException
from selenium.common.exceptions import ImeActivationFailedException
from selenium.common.exceptions import ImeNotAvailableException
from selenium.common.exceptions import InsecureCertificateException
from selenium.common.exceptions import InvalidArgumentException
from selenium.common.exceptions import InvalidCookieDomainException
from selenium.common.exceptions import InvalidCoordinatesException
from selenium.common.exceptions import InvalidElementStateException
from selenium.common.exceptions import InvalidSelectorException
from selenium.common.exceptions import InvalidSessionIdException
from selenium.common.exceptions import JavascriptException
from selenium.common.exceptions import MoveTargetOutOfBoundsException
from selenium.common.exceptions import NoAlertPresentException
from selenium.common.exceptions import NoSuchCookieException
from selenium.common.exceptions import NoSuchElementException
from selenium.common.exceptions import NoSuchFrameException
from selenium.common.exceptions import NoSuchShadowRootException
from selenium.common.exceptions import NoSuchWindowException
from selenium.common.exceptions import ScreenshotException
from selenium.common.exceptions import SessionNotCreatedException
from selenium.common.exceptions import StaleElementReferenceException
from selenium.common.exceptions import TimeoutException
from selenium.common.exceptions import UnableToSetCookieException
from selenium.common.exceptions import UnexpectedAlertPresentException
from selenium.common.exceptions import UnknownMethodException
from selenium.common.exceptions import WebDriverException


[docs]class ErrorCode:
    """Error codes defined in the WebDriver wire protocol."""

    # Keep in sync with org.openqa.selenium.remote.ErrorCodes and errorcodes.h
    SUCCESS = 0
    NO_SUCH_ELEMENT = [7, "no such element"]
    NO_SUCH_FRAME = [8, "no such frame"]
    NO_SUCH_SHADOW_ROOT = ["no such shadow root"]
    UNKNOWN_COMMAND = [9, "unknown command"]
    STALE_ELEMENT_REFERENCE = [10, "stale element reference"]
    ELEMENT_NOT_VISIBLE = [11, "element not visible"]
    INVALID_ELEMENT_STATE = [12, "invalid element state"]
    UNKNOWN_ERROR = [13, "unknown error"]
    ELEMENT_IS_NOT_SELECTABLE = [15, "element not selectable"]
    JAVASCRIPT_ERROR = [17, "javascript error"]
    XPATH_LOOKUP_ERROR = [19, "invalid selector"]
    TIMEOUT = [21, "timeout"]
    NO_SUCH_WINDOW = [23, "no such window"]
    INVALID_COOKIE_DOMAIN = [24, "invalid cookie domain"]
    UNABLE_TO_SET_COOKIE = [25, "unable to set cookie"]
    UNEXPECTED_ALERT_OPEN = [26, "unexpected alert open"]
    NO_ALERT_OPEN = [27, "no such alert"]
    SCRIPT_TIMEOUT = [28, "script timeout"]
    INVALID_ELEMENT_COORDINATES = [29, "invalid element coordinates"]
    IME_NOT_AVAILABLE = [30, "ime not available"]
    IME_ENGINE_ACTIVATION_FAILED = [31, "ime engine activation failed"]
    INVALID_SELECTOR = [32, "invalid selector"]
    SESSION_NOT_CREATED = [33, "session not created"]
    MOVE_TARGET_OUT_OF_BOUNDS = [34, "move target out of bounds"]
    INVALID_XPATH_SELECTOR = [51, "invalid selector"]
    INVALID_XPATH_SELECTOR_RETURN_TYPER = [52, "invalid selector"]

    ELEMENT_NOT_INTERACTABLE = [60, "element not interactable"]
    INSECURE_CERTIFICATE = ["insecure certificate"]
    INVALID_ARGUMENT = [61, "invalid argument"]
    INVALID_COORDINATES = ["invalid coordinates"]
    INVALID_SESSION_ID = ["invalid session id"]
    NO_SUCH_COOKIE = [62, "no such cookie"]
    UNABLE_TO_CAPTURE_SCREEN = [63, "unable to capture screen"]
    ELEMENT_CLICK_INTERCEPTED = [64, "element click intercepted"]
    UNKNOWN_METHOD = ["unknown method exception"]

    METHOD_NOT_ALLOWED = [405, "unsupported operation"]


[docs]class ErrorHandler:
    """Handles errors returned by the WebDriver server."""
[docs]    def check_response(self, response: Dict[str, Any]) -> None:
        """Checks that a JSON response from the WebDriver does not have an
        error.

        :Args:
         - response - The JSON response from the WebDriver server as a dictionary
           object.

        :Raises: If the response contains an error message.
        """
        status = response.get("status", None)
        if not status or status == ErrorCode.SUCCESS:
            return
        value = None
        message = response.get("message", "")
        screen: str = response.get("screen", "")
        stacktrace = None
        if isinstance(status, int):
            value_json = response.get("value", None)
            if value_json and isinstance(value_json, str):
                import json

                try:
                    value = json.loads(value_json)
                    if len(value.keys()) == 1:
                        value = value["value"]
                    status = value.get("error", None)
                    if not status:
                        status = value.get("status", ErrorCode.UNKNOWN_ERROR)
                        message = value.get("value") or value.get("message")
                        if not isinstance(message, str):
                            value = message
                            message = message.get("message")
                    else:
                        message = value.get("message", None)
                except ValueError:
                    pass

        exception_class: Type[WebDriverException]
        if status in ErrorCode.NO_SUCH_ELEMENT:
            exception_class = NoSuchElementException
        elif status in ErrorCode.NO_SUCH_FRAME:
            exception_class = NoSuchFrameException
        elif status in ErrorCode.NO_SUCH_SHADOW_ROOT:
            exception_class = NoSuchShadowRootException
        elif status in ErrorCode.NO_SUCH_WINDOW:
            exception_class = NoSuchWindowException
        elif status in ErrorCode.STALE_ELEMENT_REFERENCE:
            exception_class = StaleElementReferenceException
        elif status in ErrorCode.ELEMENT_NOT_VISIBLE:
            exception_class = ElementNotVisibleException
        elif status in ErrorCode.INVALID_ELEMENT_STATE:
            exception_class = InvalidElementStateException
        elif (
            status in ErrorCode.INVALID_SELECTOR
            or status in ErrorCode.INVALID_XPATH_SELECTOR
            or status in ErrorCode.INVALID_XPATH_SELECTOR_RETURN_TYPER
        ):
            exception_class = InvalidSelectorException
        elif status in ErrorCode.ELEMENT_IS_NOT_SELECTABLE:
            exception_class = ElementNotSelectableException
        elif status in ErrorCode.ELEMENT_NOT_INTERACTABLE:
            exception_class = ElementNotInteractableException
        elif status in ErrorCode.INVALID_COOKIE_DOMAIN:
            exception_class = InvalidCookieDomainException
        elif status in ErrorCode.UNABLE_TO_SET_COOKIE:
            exception_class = UnableToSetCookieException
        elif status in ErrorCode.TIMEOUT:
            exception_class = TimeoutException
        elif status in ErrorCode.SCRIPT_TIMEOUT:
            exception_class = TimeoutException
        elif status in ErrorCode.UNKNOWN_ERROR:
            exception_class = WebDriverException
        elif status in ErrorCode.UNEXPECTED_ALERT_OPEN:
            exception_class = UnexpectedAlertPresentException
        elif status in ErrorCode.NO_ALERT_OPEN:
            exception_class = NoAlertPresentException
        elif status in ErrorCode.IME_NOT_AVAILABLE:
            exception_class = ImeNotAvailableException
        elif status in ErrorCode.IME_ENGINE_ACTIVATION_FAILED:
            exception_class = ImeActivationFailedException
        elif status in ErrorCode.MOVE_TARGET_OUT_OF_BOUNDS:
            exception_class = MoveTargetOutOfBoundsException
        elif status in ErrorCode.JAVASCRIPT_ERROR:
            exception_class = JavascriptException
        elif status in ErrorCode.SESSION_NOT_CREATED:
            exception_class = SessionNotCreatedException
        elif status in ErrorCode.INVALID_ARGUMENT:
            exception_class = InvalidArgumentException
        elif status in ErrorCode.NO_SUCH_COOKIE:
            exception_class = NoSuchCookieException
        elif status in ErrorCode.UNABLE_TO_CAPTURE_SCREEN:
            exception_class = ScreenshotException
        elif status in ErrorCode.ELEMENT_CLICK_INTERCEPTED:
            exception_class = ElementClickInterceptedException
        elif status in ErrorCode.INSECURE_CERTIFICATE:
            exception_class = InsecureCertificateException
        elif status in ErrorCode.INVALID_COORDINATES:
            exception_class = InvalidCoordinatesException
        elif status in ErrorCode.INVALID_SESSION_ID:
            exception_class = InvalidSessionIdException
        elif status in ErrorCode.UNKNOWN_METHOD:
            exception_class = UnknownMethodException
        else:
            exception_class = WebDriverException
        if not value:
            value = response["value"]
        if isinstance(value, str):
            raise exception_class(value)
        if message == "" and "message" in value:
            message = value["message"]

        screen = None  # type: ignore[assignment]
        if "screen" in value:
            screen = value["screen"]

        stacktrace = None
        st_value = value.get("stackTrace") or value.get("stacktrace")
        if st_value:
            if isinstance(st_value, str):
                stacktrace = st_value.split("n")
            else:
                stacktrace = []
                try:
                    for frame in st_value:
                        line = frame.get("lineNumber", "")
                        file = frame.get("fileName", "<anonymous>")
                        if line:
                            file = f"{file}:{line}"
                        meth = frame.get("methodName", "<anonymous>")
                        if "className" in frame:
                            meth = f"{frame['className']}.{meth}"
                        msg = "    at %s (%s)"
                        msg = msg % (meth, file)
                        stacktrace.append(msg)
                except TypeError:
                    pass
        if exception_class == UnexpectedAlertPresentException:
            alert_text = None
            if "data" in value:
                alert_text = value["data"].get("text")
            elif "alert" in value:
                alert_text = value["alert"].get("text")
            raise exception_class(message, screen, stacktrace, alert_text)  # type: ignore[call-arg]  # mypy is not smart enough here
        raise exception_class(message, screen, stacktrace)

Classes

class selenium.webdriver.remote.errorhandler.ErrorCode[source]¶

Error codes defined in the WebDriver wire protocol.

ELEMENT_CLICK_INTERCEPTED = [64, ‘element click intercepted’]¶

ELEMENT_IS_NOT_SELECTABLE = [15, ‘element not selectable’]¶

ELEMENT_NOT_INTERACTABLE = [60, ‘element not interactable’]¶

ELEMENT_NOT_VISIBLE = [11, ‘element not visible’]¶

IME_ENGINE_ACTIVATION_FAILED = [31, ‘ime engine activation failed’]¶

IME_NOT_AVAILABLE = [30, ‘ime not available’]¶

INSECURE_CERTIFICATE = [‘insecure certificate’]¶

INVALID_ARGUMENT = [61, ‘invalid argument’]¶

INVALID_COOKIE_DOMAIN = [24, ‘invalid cookie domain’]¶

INVALID_COORDINATES = [‘invalid coordinates’]¶

INVALID_ELEMENT_COORDINATES = [29, ‘invalid element coordinates’]¶

INVALID_ELEMENT_STATE = [12, ‘invalid element state’]¶

INVALID_SELECTOR = [32, ‘invalid selector’]¶

INVALID_SESSION_ID = [‘invalid session id’]¶

INVALID_XPATH_SELECTOR = [51, ‘invalid selector’]¶

INVALID_XPATH_SELECTOR_RETURN_TYPER = [52, ‘invalid selector’]¶

JAVASCRIPT_ERROR = [17, ‘javascript error’]¶

METHOD_NOT_ALLOWED = [405, ‘unsupported operation’]¶

MOVE_TARGET_OUT_OF_BOUNDS = [34, ‘move target out of bounds’]¶

NO_ALERT_OPEN = [27, ‘no such alert’]¶

NO_SUCH_COOKIE = [62, ‘no such cookie’]¶

NO_SUCH_ELEMENT = [7, ‘no such element’]¶

NO_SUCH_FRAME = [8, ‘no such frame’]¶

NO_SUCH_SHADOW_ROOT = [‘no such shadow root’]¶

NO_SUCH_WINDOW = [23, ‘no such window’]¶

SCRIPT_TIMEOUT = [28, ‘script timeout’]¶

SESSION_NOT_CREATED = [33, ‘session not created’]¶

STALE_ELEMENT_REFERENCE = [10, ‘stale element reference’]¶

SUCCESS = 0¶

TIMEOUT = [21, ‘timeout’]¶

UNABLE_TO_CAPTURE_SCREEN = [63, ‘unable to capture screen’]¶

UNABLE_TO_SET_COOKIE = [25, ‘unable to set cookie’]¶

UNEXPECTED_ALERT_OPEN = [26, ‘unexpected alert open’]¶

UNKNOWN_COMMAND = [9, ‘unknown command’]¶

UNKNOWN_ERROR = [13, ‘unknown error’]¶

UNKNOWN_METHOD = [‘unknown method exception’]¶

XPATH_LOOKUP_ERROR = [19, ‘invalid selector’]¶

class selenium.webdriver.remote.errorhandler.ErrorHandler[source]¶

Handles errors returned by the WebDriver server.

check_response(response: Dict[str, Any]) → None[source]¶

Checks that a JSON response from the WebDriver does not have an
error.

Args:	response — The JSON response from the WebDriver server as a dictionary object.
Raises:	If the response contains an error message.

14 Oct 2018

Selenium is a very versatile web scraping tool that is accessible via multiple programming languages.

It’s distinguished from text-parsing scrapers like BeautifulSoup as it actually simulates a web navigation experience, enabling you to scrape website running on a lot of Javascript and iframes.

That makes Selenium especially powerful when you are in need of scraping large websites, like e-commerce sites.

However, as with large websites, the pages you scrape won’t be totally identical with one another.

Hence, error or exception handling is very, very important.

Without proper exception handling, you may face errors after errors and waste time, as any error will simply halt your scraping work.

This is especially bad when you have set up your scraping task to take place over lunch or overnight.

Missing Element

Sometimes, certain pages do not have a certain element, which is very common.

For example, you might be scraping Amazon for products’ reviews. Some products that do not have any reviews simply do not have any review element to show you.

This can be easily solved by appending a «» or None to the list that you’re populating your scrape result.

from selenium.common.exceptions import NoSuchElementException

reviews = []

for page in pages_to_scrape:
  try:
    # Insert your scraping action here
    reviews.append(driver.find_element_by_css_selector('div.review').text)
  except NoSuchElementException:
    # Just append a None or ""
    reviews.append(None)
    

Timeout Exception

Some websites are simply slow or too small that your scraping has caused their server to overload.

The latter is always bad and you shouldn’t crash other people’s websites when scraping.

In any case, timeouts (i.e. page failed to load) are common on large websites.

However, I won’t recommend catching this error unless you know from experience that the website is prone to timeouts. It can be a huge waste of resource if the website has a 0.01% chance of timeout.

from selenium.webdriver.common.by import By
from selenium.webdriver.support.ui import WebDriverWait
from selenium.webdriver.support import expected_conditions as EC
from selenium.common.exceptions import TimeoutException

driver.get("your url")
# Remove the while loop and break if you don't want to try again when it took too long
while True:
  try:
    # Define an element that you can start scraping when it appears
    # If the element appears after 5 seconds, break the loop and continue
    WebDriverWait(driver, 5).until(EC.presence_of_element_located((By.CSS_SELECTOR, "your selector")))
    break
  except TimeoutException:
    # If the loading took too long, print message and try again
    print("Loading took too much time!")

Element Click Intercepted Exception

This error happens when the element you try to click (e.g. the «next page» button) gets blocked by another element and becomes unclickable.

The common cause of this is a pop-up being triggered, or there is a chat box that appears at the bottom-right of the page.

There are a few ways to solve this. The first way is to close the pop-up.

from selenium.common.exceptions import ElementClickInterceptedException

try:
  # Tries to click an element
  driver.find_element_by_css_selector("button selector").click()
except ElementClickInterceptedException:
  # If pop-up overlay appears, click the X button to close
  time.sleep(2) # Sometimes the pop-up takes time to load
  driver.find_element_by_css_selector("close button selector").click()

You may also use Javascript to hide that element (credit to Louis’ StackOverflow answer):

from selenium.common.exceptions import ElementClickInterceptedException

try:
  # Tries to click an element
  driver.find_element_by_css_selector("button selector").click()
except ElementClickInterceptedException:
  element = driver.find_element_by_class_name("blocking element's class")
  driver.execute_script("""
            var element = arguments[0];
            element.parentNode.removeChild(element);
            """, element)

If it’s not a pop-up, the problem could be solved by scrolling away, hoping that the blocking element moves with you and away from the button/link to be clicked.

from selenium.common.exceptions import ElementClickInterceptedException

try:
  # Tries to click an element
  driver.find_element_by_css_selector("button selector").click()
except ElementClickInterceptedException:
  # Use Javascript to scroll down to bottom of page
  driver.execute_script("window.scrollTo(0, document.body.scrollHeight);")

Stale Element

Stale element happens when the element is was deleted or no longer attached to the DOM. 

Though a not very common error, some websites are prone to having this error.

When encountered with this error, you can just try again for a number of times.

from selenium.common.exceptions import StaleElementReferenceException

while True:    
  try:
    item_list.append(driver.find_element_by_id("item id").text)
  except StaleElementReferenceException:
    continue # If StaleElement appears, try again
  break # once try is successful, stop while loop

Best Practice — Error Handling & Exceptions

Only use necessary error exceptions

Catching errors and using these exceptions slows your code down significantly. It can cause a regular 1-hour scraping task to double in time especially if you wrap all your scraping actions with error exceptions.

Sometimes it’s totally inescapable, and that’s when a full coverage of error exceptions is necessary so that you can run it overnight without any worries.

However, I recommend to do a trial and error on your code and implement error exceptions only when you encounter them.

Start with a small, representative sample of your web pages to find out the type of errors that can happen.

Use placeholder element before appending to a list

If you’re scraping a few elements in a row, it’s best to assign the result of the scrape to a temporary, placeholder variable before appending to a list.

This is because if you’re appending all to their respective lists, an error in the later stages will cause your prior appended lists having more elements.

# ====================
# Use this way
# ====================
try:
  item_one_temp = driver.find_element_by_id("item one id").text
  item_two_temp = driver.find_element_by_id("item two id").text
  item_one.append(item_one_temp)
  item_two.append(item_two_temp)
except NoSuchElementException:
  item_one.append(None)
  item_two.append(None)

# ====================
# Instead of this
# ====================
try:
  item_one.append(driver.find_element_by_id("item one id").text)
  # if the next element does not exist, item_one list is already appended
  # i.e. one of your list is longer than another
  item_two.append(driver.find_element_by_id("item two id").text)
except NoSuchElementException:
  item_one.append(None)
  item_two.append(None)

Specify specific errors, unless your action plan for any error is the same

It’s useful to specify specific errors that you expect as different errors require different treatments.

Only use a broad «except» statements if you’re planning to do the same if any error arises.

I wish that I know all this before I started scraping as I had to waste a lot of time on StackOverflow. Hope this guide has been useful

With the world evolving towards software development, testing plays a vital role in making the process defect free. Selenium is one such tool that helps in finding bugs and resolve them. The Selenium Certification can help you learn all about exceptions. Exceptions in Selenium is an important concept that helps us in handling errors and avoid software failures. Through this article on Exceptions in Selenium, I will give you a complete insight into the fundamentals and various methods of handling exceptions.

In this article, I will be covering the following topics.

• Introduction to Exception Handling
• Checked vs Unchecked Exception
• Basic Example of Exception
• Types of Exceptions
• Methods of Handling Exceptions

You may also go through this recording of Exceptions in Selenium by our Experts where you can understand the topics in a detailed manner with examples.

Introduction to Exceptions

An exception is an event or a problem that arises during the execution of a program. When an exception occurs, the normal flow of program halts and an exception object is created. The program then tries to find someone that can handle the raised exception. The exception object contains a lot of debugging information, such as method hierarchy, the line number where the exception occurred, the type of exception, etc.

When you start working with Selenium webdriver, you will come across different exceptions based on the code you write. The same code some times work properly and sometimes it simply doesn’t. Whenever you develop any script, you try to give the best quality code that works fine. But Unfortunately, sometimes exceptions come as side effects to the scripts that we develop and tends to fail. That’s why handling an exception is very important.

Exception Handling mechanism follows a flow which is depicted in the above figure. But if an exception is not handled, it may lead to a system failure. That is why handling an exception is very important. Now let’s move further and understand what are the various categories of exceptions. 

Checked vs Unchecked Exception

Basically, there are 2 types of exceptions in Selenium and they are as follows:

• Checked Exception
• Unchecked Exception

Let’s understand these two exceptions in depth.

class Exception{
public static void main(String args[]){
try{
//code that may raise an exception</span>
}
catch(Exception e){
// rest of the program
}
}
}

Above code represent an exception wherein inside try block we are going to write a code that may raise an exception and then, that exception will be handled in the catch block. Having understood this, let’s move further and see different types of exceptions that cause disruption to the normal flow of execution of the program.

Types of Exceptions

• WebDriverException

WebDriver Exception comes when we try to perform any action on the non-existing driver.

WebDriver driver = new InternetExplorerDriver();
driver.get("http://google.com");
driver.close();
driver.quit();

• NoAlertPresentException

When we try to perform an action i.e., either accept() or dismiss() which is not required at a required place; gives us this exception.

try{
driver.switchTo().alert().accept();
}
catch (NoAlertPresentException E){
E.printStackTrace();
}

• NoSuchWindowException

When we try to switch to a window which is not present gives us this exception:

WebDriver driver = new InternetExplorerDriver();
driver.get("http://google.com");
driver.switchTo().window("Yup_Fail");
driver.close();

In the above snippet, line 3 throws us an exception, as we are trying to switch to a window that is not present.

• NoSuchFrameException

Similar to Window exception, Frame exception mainly comes during switching between the frames.

WebDriver driver = new InternetExplorerDriver();
driver.get("http://google.com");
driver.switchTo().frame("F_fail");
driver.close();

In the above snippet, line 3 throws us an exception, as we are trying to switch to a frame that is not present.

• NoSuchElementException

This exception is thrown when we WebDriver doesn’t find the web-element in the DOM.

WebDriver driver = new InternetExplorerDriver();
driver.get("http://google.com");
driver.findElement(By.name("fake")).click();

Now see move ahead in this exceptions in Selenium article and see various methods used to handle Exceptions.

Methods of Handling Exceptions

1. Try: try block is used to enclose the code that might throw an exception.
2. Catch: catch block is used to handle the Exception. It must be used after the try block only
3. Finally: finally block is a block that is used to execute important code such as closing connection, stream etc. It is always executed whether an exception is handled or not.
4. Throw: throw” keyword is used to throw an exception.

Throws: The “throws” keyword is used to declare exceptions. It doesn’t throw an exception. It specifies that there may occur an exception in the method. It is always used with method signature.

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Let’s see a small example to understand how a thrown exception can be handled using exception methods. Let’s have a look at the code.

package Edureka;
import java.util.concurrent.TimeUnit;
import java.util.concurrent.TimeoutException;
import org.openqa.selenium.By;
import org.openqa.selenium.NoAlertPresentException;
import org.openqa.selenium.NoSuchElementException;
import org.openqa.selenium.WebDriver;
import org.openqa.selenium.chrome.ChromeDriver;
import org.openqa.selenium.firefox.FirefoxDriver;
import org.openqa.selenium.support.ui.ExpectedConditions;
import org.openqa.selenium.support.ui.Wait;
import org.openqa.selenium.support.ui.WebDriverWait;
public class Exceptionhandling {
public static void main(String[] args) throws InterruptedException, TimeoutException{
System.setProperty("webdriver.firefox.driver", "C:Selenium-java-edurekachromedriver_win32chromedriver.exe");
WebDriver driver = new FirefoxDriver();
WebDriverWait wait = new WebDriverWait(driver, 10);
driver.get("https://www.google.com");
try{
driver.findElement(By.xpath("//*[@id='register']")).click();
}catch (Exception e) {
System.out.println("Register element is not found.");
throw(e);
}
System.out.println("Hello");
}
}

Let’s understand the functionalities of each method in depth.

Try Method

In the above code, I have used a try block to enter the statement that throws the exception. Here, this statement driver.findElement(By.xpath(“//*[@id=’register’]”)).click(); throws exception because in the Google Search page Selenium cannot locate the particular element. So, once the exception is thrown, the normal execution of the program will be interrupted. Now, let’s see how it is handled in the catch block.

Catch Method

The task here is to handle this exception and continue the execution of the program. For that, I have written a catch block which will handle the thrown exception. It should always be written after the try block. So when you execute the program, it will print the rest of the statements.

Throw Method

As you all know throw is a keyword which is used to pass an exception. But, the interesting thing is that irrespective of the fact that catch block has handled the exception or not, throw()will still raise an exception. This results in disrupting the normal flow of execution of the program. In the above code, after the catch block has handled the exception,  I have written a statement throw(e); to throw an exception.

Throws Method

Throws declaration is used to declare an exception. For example, It can declare Interrupted exception, timeout exception, etc. This is how various methods can be used to handle the raised exception in the program.

With this, we come to an end of this article on Exceptions in Selenium. I hope you understood the concepts and helped in adding value to your knowledge.

If you wish to learn Selenium and build a career in the testing domain, then check out our interactive, live-online Selenium Certification, that comes with 24*7 support to guide you throughout your learning period.

Got a question for us? Please mention it in the comments section of Exceptions in Selenium article and we will get back to you.