Grokking The Object Oriented Design Interview

Grokking Object Oriented Design

grokking the object oriented design interview Object-oriented design has always been a critical part of the software engineering interview process. Most of the engineers struggle with the object-oriented design interviews , partly because of their lack of experience in laying down the design of a complex system, and partly because of the unstructured nature of OODI.

Course: Grokking the Object Oriented Design Interview Object-oriented design has always been a critical part of the software engineering interview process. Most of the engineers struggle with the object-oriented design interviews , partly because of their lack of experience in laying down the design of a complex system, and partly because of the unstructured nature of OODI.

Educative – Grokking the Object Oriented Design Interview Available now at Coursecui.com, Just pay 64, Design an Airline Management System.

Design Gurus â Grokking The Object Oriented Design Interview Object-oriented design has always been a critical part of the software engineering interview process. Most of the engineers struggle with the object-oriented design interviews , partly because of their lack of experience in laying down the design of a complex system, and partly because of the unstructured nature of OODI.

Oo Analysis And Design

OO Analysis and Design is a structured method for analyzing and designing a system by applying object-oriented concepts. This design process consists of an investigation into the objects constituting the system. It starts by first identifying the objects of the system and then figuring out the interactions between various objects.

The process of OO analysis and design can be described as:

We need a standard method/tool to document all this information for this purpose we use UML. UML can be considered as the successor of object-oriented analysis and design. UML is powerful enough to represent all the concepts that exist in object-oriented analysis and design. UML diagrams are a representation of object-oriented concepts only. Thus, before learning UML, it is essential to understand OO concepts.

Letâs find out how we can model using UML.

Dont Miss: How To Interview A Technical Writer

Even Seasoned Developers Grapple With Object Oriented Design Interview Questions

Due to the unstructured nature of object oriented design interviews, theres no standard answer. As a result, many developers find them tough.

And thats where FAANG interview prep materials come in.

This post contains affiliate links. I may receive compensation if you buy something. Read my disclosure for more details.

Today were reviewing the Grokking the Object Oriented Design Interview course on Educative.

This object oriented design course was designed by hiring managers of Google, Facebook, Amazon and Microsoft. It contains handpicked case studies that are regularly asked at FAANG interviews.

In addition, the course enables engineers to handle various object oriented design scenarios with confidence.

An excellent set of problems, I have been asked Parking Lot and Flight Reservation system in two interviews. This course helped me brush up object oriented analysis techniques that I had almost forgotten. Thanks guys for this content.

Billy Hu, Software Engineer at Microsoft

Lets take a closer look at what this course has to offer.

Looking for some more FAANG interview courses? Check out our review of Grokking the System Design Interview.

This FAANG interview prep course is separated into two sections:

You May Like: What Are Questions You Get Asked At A Job Interview

Don’t Miss: How To Dress For A Job Interview

How Do You Design A Url Shortening Service Like Googl Or Bitly

This one is another common System design questions. You have given a long URL, how would you design service that would generate a shorter and unique alias for it? If you are not familiar with URL shortener service have a look at some of the popular ones like goo.gl from Google and bit.ly which is used by Twitter.

Make sure to provide database schema and rationale behind some design decisions like how long you keep the data, how to get stats and analytics etc. If you get stuck, you can follow the solution given on Grokking the System Design Interview course on Educative.

How To Approach Ood Interview Questions

When it comes to Object Oriented Design interview questions, interviewers are trying to assess your nuanced understanding of complex problems and how you transform requirements into comprehensible classes and subclasses.

OOD questions generally follow similar patterns. During the job interview, you will be given a vague design problem and a set of constraints. Then, you need to leverage your design skills to figure out the level of solution that the interviewer is looking for.

You need to think about what functionality is needed and come up with a workable using design principles and a programming language of your choice.

Note: For OOD interviews, top tech companies prefer mainstream object-oriented programming languages like Java, Python, C+, JavaScript, Ruby, and more.

Interviewers care most about the right balance between a solution that works immediately that is adaptable and flexible to change in the future. To simplify things, you can take the following approach for any OOD question you encounter:

Don’t Miss: What To Wear To A Tech Interview

Design Amazon / Flipkart: Build An Online Shopping Platform

An interviewer will be looking for the basic functionality of necessary features like signup and logic. They will also be assessing the following:

• Discoverability: How will a buyer be able to discover a product? How will their search display results?
• Cart & Checkout: Users expect a checkout process and virtual to behave a certain way. How will the frontend design adhere to these best practices while also implementing new or innovative checkout semantics?
• Payment Methods: Users should be able to pay with credit cards, gift cards, etc. How will the payment method work? What new functionalities can be added to improve payment processes?
• Product Reviews & Ratings: Ratings improve online shopping experiences. When and how can a user post a review or a rating? How will you track useful reviews and de-prioritize less useful reviews?

How To Design A Limit Order Book

A limit order book is used in stock exchanges to match a buy order with a sell order based on price and time priority. How would you go about that? Which data structure you will use? Remember, the speed of matching is key and also the reliability. If you need a refresher on Data Structure then you can check out Data Structure and Algorithm in Java course and If you feel stuck you can check out my solution here.

Recommended Reading: Exit Interview Questions For Voluntary Termination

Section : Object Oriented Design Case Studies

There are 16 design case studies:

This section sets the parameters of the project such as:

floors entrances & exits parking tickets payment types

vehicle capacity parking spots with vehicle size variance

vehicle types hourly pricing structure

And much more.

This section addresses main Actors in the system such as:

Admin responsible for modifying parking lot specs

Customer receive and pay for parking ticket

Parking Attendant assist customers with their tasks

System display messages on info panels, assign and remove vehicles

And from there, youll examine the top use cases for parking lot object oriented design:

• parking floor add, remove, edit
• parking spot add, remove, edit
• take & scan ticket

Activity Diagrams offer a series of potential activities and results based on those activities.

For example, this diagram observes the activity of the ticket being paid:

As you can see, many activities are straightforward.

For example, if the customer inserts the credit card into the card reader, the next step is for the system to read the credit card details.

But there are other activities that have multiple potential outcomes. For example, Payment successful? can either be successful or produce an error. This will alter the processes moving forward.

v. Code

You May Like: How To Rate Interview Candidates

Review Of Grokking The Object Oriented Design Interview

Update: The course has been taken off from Educative, and can be purchased on DesignGurus platform for lifetime access.

Please consider supporting us by signing up for a paid Medium account.

Today, well review another very popular course listed at Educative.io platform: Grokking the Object Oriented Design Interview. Writing object oriented

Also Check: Who Was Interviewed On Npr This Morning

Design A Hotel Management System

Youll want to make sure you cover:

• Room Complexity: How will the system support different room types within the same hotel?
• Alerts: How will the system remind users that their check-in date is approaching? What other alerts might be useful to factor in?
• Customization: How would users make special requests on their room? What kind of special requests would be supported?
• Cancellation / Modification: How would the system treat booking cancellation ? What about other changes? What types of modifications would be covered?

How To Design Facebook’s Newsfeed What Kind Of Algorithm Will You Use

The newsfeed is an important part of Facebook which allows a user to see what’s happening around his world which includes friends and families, the pages he has liked, the group he has followed, and of-course the Facebook Ads.

The job of the Newsfeed algorithm is to show messages which are most important for the user and which can generate high engagement. Obviously, messages from friends and family should take priority. If you feel not going anywhere and stuck, you can follow the solution on System Design Interviews: Grokking the System Design Interview.

Also Check: How To Practice For Interview Questions

Requirements And Goals Of The System

The user can have two types of accounts: 1) Checking, and 2) Savings, and should be able to perform the following five transactions on the ATM:

Design Facebooka Social Network

A social network like Facebook requires many relationships and interconnected networks. It should allow for a lot of variance, personalization, and recommendation systems using ML components. Your answer should ideally discuss:

• Discoverability: How will users search for other users profiles? Will there be ML components in place for this?
• Following: How will users follow or unfollow other users without becoming a direct connection?
• Groups / Pages: How can members create groups, pages, and profiles?
• Privacy: How does the system handle privacy lists with certain content to be displayed only to specified connections?
• Alerts: How will users be notified for pre-selected events?

Also Check: Java Basic Concepts For Interview

How Would You Create Your Own Instagram

Instagram is a photo-sharing application that provides some custom filters to enhance your photo quality. Your application should have photo upload functionality, tagging photos for search, and some basic filters. If you could add share or social network that could be great. Btw, if you stuck, you can see the free solution provided on the Educative’s Grokking System design course as well.

Design Amazon / Flipkart

Beyond the basic functionality , interviewers will be looking for the following:

• Discoverability: How will the buyer discover a product? How will the search surface results?
• Cart & Checkout: Users expect the cart and checkout to behave in a certain way. How will the design adhere to such known best practices while also introducing innovative checkout semantics like One-Click-Purchase?
• Payment Methods: Users can pay using credit cards, gift cards, etc. How will the payment method work with the checkout process?
• Product Reviews & Ratings: When can a user post a review and a rating? How are useful reviews tracked and less useful reviews de-prioritized?

You May Like: What Should You Bring To An Interview

Design A Car Rental System

Candidates should be able to discuss the following:

• Identification: How will each vehicle be uniquely identified and located within the parking garage?
• Fees: How would the system collect a late fee for late returns?
• Logs: How would the system maintain a log for each vehicle and for each member?
• Customization: How would the system handle members requests for additional services like roadside assistance, full insurance, and GPS?

Resources That Help Me Land A Job At Fang

In about the same time last year, I started to prepare for interviews of big tech like FAANG. In one of my posts, I talked about Leetcodes role in landing the job. I think it will help more to list all resources I had used to make this come true.

• System design: Grokking the System Design Interview and Designing Data-Intensive Applications

System design is increasingly important in FANG interview because the employers not only want a programmer, but an engineer who know how to build scalable systems. A candidate is expected to know different perspectives of a system, resources like storage, memory, network etc. The candidate should also talk about trade off when a particular decision is made. Grokking the System Design Interview is the best system design materials so far. It covers quite a lot of common design topics and examples to which it applies theories. The course is quite useful for beginners.

• Cracking the Coding Interview and CTCI github

This book literally opened the door to the interviews in big tech. I bought this book a couple years ago when I got my first phone interview from FANG. It helped me understand what the interview processes look like, from HR screening to online assessment to phone interview to onsite interview. The process varies from company to company. Reading the first chapter gave me good expectation because of the great details.

• Algorithms course and Algorithms

• Patience and Determination

Previous posts:

Recommended Reading: How To Do A Successful Interview

Design An Online Stock Brokerage System

A good answer would cover these points:

• Watchlists: How would the system handle watchlists created by the user to save/monitor specific stocks?
• Transaction Types: How would the system handle different transaction types, e.g. stop loss and stop limit order? What types would be supported?
• Stock Lots: How will the system differentiate between different lots of the same stock for reporting purposes if a user has bought the same stock multiple times?
• Reporting: How will the system generate reports for monthly, quarterly, and annual updates?

Design A Movie Ticket Booking System

Interviewers would be keen on seeing the following points in your answer:

• Duplication: How are you handling instances, such as the same cinema having multiple cinema halls showing different movies simultaneously? Or the same movie being shown at different times in the same cinema/hall?
• Payment Handling: What would be the process for a user to purchase a ticket?
• Selection: How would user a pick a seat, ensuring its not already booked by someone else?
• Price Variances: How would discounted pricing be considered? For example, for students or children.

Don’t Miss: What Questions To Ask A Product Manager In An Interview

More Kinda Related Python Answers

For the best overall, we recommend Cracking the Coding Interview. For newbies, we recommend Programming Interviews Exposed. And for the best value, we think Elements of Programming Interviews in Java is the way to go.

This book introduced the concept of Design Pattern in Software development. They are testified and well-proved since they have been built upon the knowledge and experience of expert software developers.

Lets you provide a substitute or placeholder for another object. A proxy controls access to the original object, allowing you to perform something either before or after the request gets through to the original object. The pattern allows you to produce different types and representations of an object using the same construction code. Lets you produce families of related objects without specifying their concrete classes.

• Command design pattern is useful to abstract the business logic into discrete actions which we call commands.
• And for the best value, we think Elements of Programming Interviews in Java is the way to go.
• We cant say by looking at an object whether it connects with a database or not when it obtains connections from a locator.
• Factory Pattern allows the sub-classes to choose the type of objects to create.
• Python Program to count the number of lowercase letters and uppercase letters in a string.
• In addition, youll learn about how to speak to interviewers to advance to the next level.

How Do You Design An Elevator Of The Lift System

We All know about Elevators and Lift as most of us use it. You might have seen them in pairs and in some big office buildings you can see 3 to 4 lifts. You need to design software for that so that it can reach use quickly on different levels. You can assume you have two lifts and a 10-floor building.

If you need some guidance then I suggest you check out Preparing for the System Design Interview Course on Udemy, where Rajat Mehta has a whole case study to solve this problem. You will also learn about high-level design, low-level design, and Database design in this masterpiece.

Don’t Miss: How To Interview A Ux Designer