Async script execution in Selenium Java - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to execute an asynchronous JavaScript script using Selenium WebDriver.

Selenium Java

JavascriptExecutor js = (JavascriptExecutor) driver;
js.[1]("window.setTimeout(arguments[arguments.length - 1], 500);", new Object[] {});

Drag options to blanks, or click blank then click option'

AexecuteJavaScript

BexecuteAsyncScript

CexecuteScript

DrunAsyncScript

Attempts:

3 left

💡 Hint

Common Mistakes

Using executeScript instead of executeAsyncScript causes the script to run synchronously.

The executeAsyncScript method runs JavaScript asynchronously in Selenium WebDriver. It waits for the callback to be called before continuing.

2fill in blank

medium

Complete the code to pass a callback function to the asynchronous JavaScript executed by Selenium.

Selenium Java

Object result = js.executeAsyncScript("var callback = arguments[[1]]; window.setTimeout(function() { callback('done'); }, 300);");

Drag options to blanks, or click blank then click option'

A0

B1

Carguments.length - 1

Darguments.length

Attempts:

3 left

💡 Hint

Common Mistakes

Using 0 or 1 as the index causes the callback to be undefined.

The callback function is always the last argument in the arguments array, so its index is arguments.length - 1.

3fill in blank

hard

Fix the error in the asynchronous script execution code by choosing the correct method call.

Selenium Java

js.[1]("window.setTimeout(arguments[arguments.length - 1], 1000);");

Drag options to blanks, or click blank then click option'

AexecuteAsyncScript

BexecuteScript

CrunScript

DrunAsync

Attempts:

3 left

💡 Hint

Common Mistakes

Using executeScript causes the script to run synchronously and not wait for the callback.

Only executeAsyncScript supports asynchronous JavaScript execution with a callback in Selenium.

4fill in blank

hard

Fill both blanks to correctly execute an async script that returns a value after delay.

Selenium Java

Object result = js.[1]("var callback = arguments[[2]]; setTimeout(function() { callback('success'); }, 200);");

Drag options to blanks, or click blank then click option'

AexecuteAsyncScript

BexecuteScript

Carguments.length - 1

D0

Attempts:

3 left

💡 Hint

Common Mistakes

Using executeScript instead of executeAsyncScript.

Using 0 instead of arguments.length - 1 for callback index.

The method executeAsyncScript runs async scripts, and the callback is at arguments.length - 1.

5fill in blank

hard

Fill all three blanks to create a map of word lengths (keys) to lengths plus one (values), filtering only words longer than 4 characters.

Selenium Java

Map<Integer, Integer> lengths = words.stream()
    .filter(word -> word.length() [1] 4)
    .collect(Collectors.toMap(word -> word.[2], word -> word.length() [3] 1));

Drag options to blanks, or click blank then click option'

A>

Blength()

C+

D<

Attempts:

3 left

💡 Hint

Common Mistakes

Using '<' instead of '>' in filter.

Using word instead of word.length() for the key.

Using '-' instead of '+' for increment.

The filter keeps words with length greater than 4. The key is the word's length(), and the value adds 1 to the length.