Cognizant Interview Questions and Answers

Custom hooks in React are reusable functions that allow you to extract component logic into separate functions for better code organization and reusability.

• Custom hooks are created using the 'use' prefix and can be used to share logic between components.

• Use cases for custom hooks include fetching data from an API, handling form state, managing local storage, and more.

• Example of a custom hook for API call: const useFetc...read more

useMemo is used to memoize a value, while useCallback is used to memoize a function.

• useMemo is used to memoize a value and recompute it only when its dependencies change.

• useCallback is used to memoize a callback function and prevent unnecessary re-renders.

• Example: useMemo can be used to memoize the result of a complex computation, while useCallback can be used to memoize an event handler function.

Class-based components use ES6 classes and have lifecycle methods, while functional components are simpler and use functions.

• Class-based components use ES6 classes to create components, while functional components are created using functions.

• Class-based components have lifecycle methods like componentDidMount and componentDidUpdate, while functional components do not.

• Functional components are simpler and more lightweig...read more

Implementing the lifecycle of a React component in a functional component

• Use the useEffect hook to replicate lifecycle methods like componentDidMount, componentDidUpdate, and componentWillUnmount

• Pass an empty array as the second argument to useEffect to mimic componentDidMount

• Pass a variable or state as the second argument to useEffect to mimic componentDidUpdate

• Return a cleanup function inside useEffect to mimic compo...read more

Various state management techniques in React include Context API, Redux, and local state.

• Context API: React's built-in solution for passing data through the component tree without having to pass props down manually at every level.

• Redux: A popular state management library for React applications, allowing for a centralized store to manage application state.

• Local state: Managing state within individual components using us...read more

Redux is a predictable state container for JavaScript apps. Middlewares are functions that intercept actions before they reach the reducer.

• Redux follows a unidirectional data flow architecture.

• Middlewares in Redux are functions that can intercept, modify, or dispatch actions.

• Common use cases for middlewares include logging, asynchronous API calls, and handling side effects.

• Examples of popular Redux middlewares are Redu...read more

Hoisting in JavaScript is the behavior where variable and function declarations are moved to the top of their containing scope during the compilation phase.

• Variable declarations are hoisted to the top of their scope, but not their initializations.

• Function declarations are fully hoisted, meaning they can be called before they are declared.

• Hoisting can lead to unexpected behavior if not understood properly.

Event bubbling is the propagation of events from the target element up through its ancestors in the DOM tree.

• Events triggered on a child element will 'bubble up' and trigger on parent elements.

• Event listeners can be attached to parent elements to handle events from multiple child elements.

• Stopping event propagation can be done using event.stopPropagation() or event.stopImmediatePropagation().

Block scope and function scope are two types of scopes in JavaScript that determine the visibility and accessibility of variables.

• Block scope refers to the visibility of variables within a block of code enclosed by curly braces. Variables declared with 'let' and 'const' have block scope.

• Function scope refers to the visibility of variables within a function. Variables declared with 'var' have function scope.

• Variables de...read more

Yes, I have experience working with semantic tags in HTML.

• Used semantic tags like <header>, <nav>, <main>, <section>, <article>, <aside>, <footer> for better structure and SEO.

• Understand the importance of using semantic tags for accessibility and search engine optimization.

• Semantic tags help in organizing content and making it more readable for developers and browsers.

Various methods for creating an object in JavaScript include object literals, constructor functions, ES6 classes, and Object.create() method.

• Object literals: var obj = { key: value };

• Constructor functions: function ObjectName() { this.key = value; } var obj = new ObjectName();

• ES6 classes: class ClassName { constructor() { this.key = value; } } var obj = new ClassName();

• Object.create() method: var obj = Object.create(pr...read more

Shallow copy only copies the references of nested objects, while deep copy creates new copies of nested objects.

• Shallow copy creates a new object but does not create copies of nested objects, only copies their references.

• Deep copy creates a new object and also creates new copies of all nested objects.

• Shallow copy can be achieved using Object.assign() or spread operator, while deep copy can be achieved using JSON.parse(...read more

The code will throw an error because 'a' is declared but not initialized.

• The code will result in a ReferenceError because 'a' is declared but not assigned a value.

• Variables declared with 'const' must be initialized at the time of declaration.

• Initializing 'a' with a value before calling test() will prevent the error.

CSS can be used to arrange elements in a row and column layout using flexbox or grid layout properties.

• Use display: flex; for a row layout and display: flex; flex-direction: column; for a column layout

• Use justify-content and align-items properties to align items in the main axis and cross axis respectively

• For grid layout, use display: grid; and grid-template-columns or grid-template-rows to define the layout

Yes, I have utilized CSS preprocessors such as SASS and LESS.

• I have experience using SASS to streamline my CSS workflow by utilizing variables, mixins, and nesting.

• I have also worked with LESS to improve code organization and maintainability through features like variables and functions.

The color applied will be based on the specificity of the selector, with ID having higher specificity than class.

• ID has higher specificity than class in CSS

• Color applied will be based on the selector with higher specificity

• Example: If ID selector has color red and class selector has color blue, the color applied will be red

I am a UiPath Developer with experience in automating various business processes.

• Developed automation solutions using UiPath for data entry tasks

• Integrated UiPath robots with APIs to automate data retrieval and processing

• Worked on projects to automate invoice processing and report generation

• Implemented error handling mechanisms and logging in UiPath workflows

ReFramework is a template in UiPath for building robust, scalable, and reusable automation projects.

• ReFramework is a template that includes Dispatcher and Performer components for handling transactions.

• Dispatcher is responsible for reading input data and adding it to a queue.

• Performer processes items from the queue, performs the necessary actions, and updates the status of each transaction.

• DataTable transaction approac...read more

Execute query is used to retrieve data from a database, while execute non-query is used to perform operations that do not return data.

• Execute query is used for SELECT statements to retrieve data from a database.

• Execute non-query is used for INSERT, UPDATE, DELETE statements that do not return data.

• Execute query returns a result set, while execute non-query returns the number of rows affected.

• Examples: Execute query - S...read more

Switch statement is used for multiple conditions, while if-else statement is used for binary conditions.

• Switch statement is more efficient when there are multiple conditions to check.

• If-else statement is more flexible as it can handle complex conditions.

• Switch statement uses 'case' and 'break' keywords, while if-else statement uses 'if', 'else if', and 'else'.

Datatable is used to store and manipulate data in UiPath. Connection string is used to establish a connection to a database.

• Datatable is a structured data type used to store information in rows and columns.

• You can use activities like 'Build Data Table' to create a new datatable or 'Read Range' to read data from an Excel file into a datatable.

• Connection string is a string that contains information about how to connect t...read more

Project roles and responsibilities define tasks and expectations for team members to ensure project success.

• Project Manager: Oversees project planning, execution, and closure. Example: Coordinating team meetings and tracking progress.

• Team Members: Execute specific tasks assigned to them. Example: Developers coding features based on requirements.

• Stakeholders: Provide input and feedback throughout the project. Example: C...read more

There are multiple ways to call server side code from client side, including AJAX, WebSockets, and REST API calls.

• AJAX

• WebSockets

• REST API calls

To create a new request type in ITSM, follow these steps.

• Navigate to the Service Catalog in the ITSM module.

• Click on 'Create New' to start creating a new request type.

• Fill in the necessary details such as name, description, and category.

• Define the workflow for the request type, including approval processes and assignment rules.

• Test the new request type to ensure it functions correctly.

• Publish the request type for users...read more

Restrict characters for 'Investment' field in incident table to 500 characters using UI policy.

• Create a UI policy on the incident table

• Add a condition to check the length of the 'Investment' field

• Set the UI policy action to display an error message if the character limit is exceeded

GFST submit is used to submit a GlideFormState object in ServiceNow.

• GFST submit is used to save the current state of a form in ServiceNow.

• It is commonly used in client-side scripts to save form data without refreshing the page.

• GFST submit can be used to trigger business rules and workflows upon form submission.

Yes, 'IT Service Manager' role description and short description should be visible.

• Role description should clearly outline the responsibilities and requirements of the IT Service Manager position

• Short description should provide a brief overview of the role to attract potential candidates

• Both descriptions should be easily accessible on the job posting or company website

Client scripts in ServiceNow are used to automate processes on the client side.

• onChange

• onLoad

• onSubmit

Client script runs before UI Policy due to the order of execution in ServiceNow.

• Client script runs before UI Policy because it is executed on the client side before the form is submitted.

• UI Policy runs after Client script as it is applied after the form is submitted.

• Client script is used for field-level validation and manipulation, while UI Policy is used for controlling field visibility and mandatory fields.

Business rules in ServiceNow can be categorized as before, after, async, and synchronous. After business rules run after a record is inserted or updated, while async business rules run in the background.

• Types of business rules in ServiceNow: before, after, async, synchronous

• After business rules run after a record is inserted or updated

• Async business rules run in the background without blocking the user interface

• Differe...read more

Yes, the order of Business rules can be changed.

• Yes, the order of Business rules can be changed by adjusting the order in which they are executed in the Business rule list.

• This can be done by changing the 'Order' field value in the Business rule record.

• Business rules with lower 'Order' values will be executed before those with higher 'Order' values.

• Changing the order of Business rules can impact the overall behavior an...read more

Email notifications in ServiceNow can be customized using scripts for dynamic content and conditions.

• Use 'Email Notification' module to create notifications based on specific conditions.

• Scripts can be added to the 'Condition' field to determine when to send an email.

• Example: Use 'current.state.changes()' to trigger an email when the state changes.

• Utilize 'Email Template' for consistent formatting and dynamic content in...read more

The isolate checkbox is used to prevent a script from running in the global scope.

• Prevents variables and functions from being accessed globally

• Helps in avoiding conflicts with other scripts

• Useful when developing complex applications with multiple scripts

xml() and xml() wait are both used in ServiceNow to parse XML data, but xml() wait is used for asynchronous parsing.

• xml() is used for synchronous parsing of XML data in ServiceNow

• xml.wait() is used for asynchronous parsing of XML data in ServiceNow

• xml() is blocking, while xml.wait() allows other operations to continue while parsing XML data

To achieve UI actions in ServiceNow, use client scripts for client-side and business rules for server-side execution.

• Use Client Scripts for UI actions that need to run on the user's browser.

• Use Business Rules for server-side logic that should execute on record changes.

• Example: A Client Script can validate a form before submission, while a Business Rule can update a field based on that submission.

• You can call server-sid...read more

Update 'Investment' field in incident table from Standard to SMA for all records

• Create a script to update the 'Investment' field in incident table for all records

• Use a loop to iterate through each record and update the 'Investment' field value from Standard to SMA

Yes, we can use 'previous' in Business rule to access the previous value of a field.

• Use 'previous' keyword in a Business rule to access the previous value of a field

• Can be helpful in comparing current and previous values for triggering actions

• Example: gs.info('Previous value: ' + current.previous.value)

get reference is used to retrieve a reference to a record in another table

• Used to establish relationships between records in different tables

• Allows for easy access to related information

• Can be used in scripts to retrieve data from related records

I am a Senior Automation Test Engineer with 5+ years of experience in designing and implementing automated testing frameworks.

• 5+ years of experience in automation testing

• Proficient in designing and implementing automated testing frameworks

• Strong knowledge of testing tools like Selenium, Appium, and JUnit

• Experience in creating test scripts and executing test cases

• Ability to analyze test results and identify defects

The syntax for using driver.findElement in Selenium is driver.findElement(By locator)

• Use driver.findElement(By locator) to locate a single element on the web page

• Specify the locator strategy (e.g. By.id, By.name, By.xpath) to identify the element

• Example: WebElement element = driver.findElement(By.id("username"));

Different types of assertions and syntax for hard assertion in TestNG

• Types of assertions: Hard assertions and Soft assertions

• Syntax for hard assertion in TestNG: Assert.assertEquals(expected, actual)

Types of wait mechanisms include implicit wait, explicit wait, fluent wait, and thread.sleep.

• Implicit wait: Waits for a certain amount of time before throwing a NoSuchElementException.

• Explicit wait: Waits for a certain condition to occur before proceeding further.

• Fluent wait: Waits for a condition to be true with a specified polling frequency.

• Thread.sleep: Pauses the execution for a specified amount of time.

Frames in Selenium can be managed using switchTo() method to navigate between frames.

• Use driver.switchTo().frame() method to switch to a frame by index, name or WebElement

• Use driver.switchTo().defaultContent() method to switch back to the main content

• Use driver.switchTo().parentFrame() method to switch to the parent frame

Use a Set data structure to remove duplicates from an array of strings.

• Create a Set from the array to automatically remove duplicates

• Convert the Set back to an array to get the unique values

List, Set, and Map are different types of collections in Java used to store and manipulate groups of objects.

• List is an ordered collection that allows duplicate elements. Example: ArrayList, LinkedList

• Set is a collection that does not allow duplicate elements. Example: HashSet, TreeSet

• Map is a collection of key-value pairs where each key is unique. Example: HashMap, TreeMap

I would analyze the user stories and application functionality to identify the root cause of the mismatch and work towards resolving it.

• Review the user stories and application functionality to understand the discrepancies

• Communicate with stakeholders to clarify requirements and expectations

• Update test cases and automation scripts to align with the corrected user stories

• Collaborate with developers to address any underly...read more

I have over 5 years of experience in automation testing, with a focus on creating and executing test scripts for web applications.

• Developing automation test scripts using tools like Selenium and TestNG

• Creating test plans and test cases based on requirements

• Executing test cases and reporting defects

• Collaborating with developers and QA team to ensure quality of the product

• Participating in Agile ceremonies such as sprint ...read more

Demonstrating feature file step definitions with different sets of data in a previous project scenario

• Create a feature file with a scenario outline that includes placeholders for different sets of data

• Write step definitions that use the placeholders to run the scenario with different data sets

• Use data tables or examples in the feature file to provide the different sets of data

• Run the scenario with different data sets t...read more

To count URLs in an HTML page using Selenium and open the URL containing your name, you can use a combination of Selenium WebDriver methods and regular expressions.

• Use Selenium WebDriver to navigate to the HTML page and retrieve its source code

• Use regular expressions to identify and count the URLs in the source code

• Iterate through the list of URLs to find the one containing your name

• Use Selenium WebDriver to open the U...read more

Use regular expressions to separate letters and digits from a string in Java.

• Use the String class's split() method with a regular expression to separate letters and digits.

• Create a regular expression pattern that matches either letters or digits.

• Store the separated letters and digits in separate arrays.