Table Of ContentThe Complete
Coding Interview
Guide in Java
An effective guide for aspiring Java developers to ace
their programming interviews
Anghel Leonard
BIRMINGHAM—MUMBAI
The Complete Coding Interview Guide in Java
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Contributors
About the author
Anghel Leonard is a chief technology strategist with more than 20 years’ experience
in the Java ecosystem. In his daily work, he is focused on architecting and developing
Java-distributed applications that empower robust architectures, clean code, and high
performance. He is also passionate about coaching, mentoring, and technical leadership.
I would like to thank the Packt team for making this book possible.
About the reviewer
Tejaswini Mandar Jog is a passionate and enthusiastic Java trainer. She has more than 12
years’ experience in the IT training field, specializing in Java, J2EE, Spring, Spring Cloud,
microservices, and relevant technologies.
She has worked with many renowned corporate companies on training and skill
enhancement programs. She is also involved in the development of projects using
Java, Spring, and Hibernate and is the author of three books related to Spring, reactive
programming, and modular programming.
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Table of Contents
Preface
Section 1: The Non-Technical Part of
an Interview
1
Where to Start and How to Prepare for the Interview
The novice interview roadmap 4 I got an interview! Now what? 23
Know yourself 4 The phone screening stage 23
Know the market 8 Going to in-person interviews 24
Avoiding common mistakes 24
It’s all about getting the right
experience 11 Summary 25
Start something 11
It’s time to shine online 12
Time to write your resume 18
What resume screeners are looking for 18
How long the resume should be 18
How to list your employment history 19
List the most relevant projects (top five) 19
Nominate your technical skills 20
LinkedIn resume 21
The job application process 22
Finding companies that are hiring 22
Submitting the resume 23
ii Table of Contents
2
What Interviews at Big Companies
Look Like
Interviews at Google 28 Interviews at Facebook 29
Interviews at Amazon 28 Interviews at Crossover 30
Interviews at Microsoft 29 Summary 31
3
Common
Non-Technical Questions and How To Answer Them
What is the purpose of non- Why are you looking to change
technical questions? 34 jobs? 37
What is your experience? 35 What is your salary history? 38
What is your favorite Why should we hire you? 38
programming language? 35 How much money do you want
What do you want to do? 36 to make? 38
What are your career goals? 36 Do you have a question for me? 40
What's your working style? 36 Summary 40
4
How to Handle Failures
Accepting or rejecting an offer 42 Don’t lose confidence in
Failure is an option 42 yourself – sometimes, they
don’t deserve you! 44
A company can reject you for a
lot Summary 45
of reasons 43
Getting feedback after the interview 43
Objectively identifying and
eliminating
the mismatches 44
Don’t form an obsession for a
company 44
Table of Contents iii
5
How to Approach a Coding Challenge
Technical quiz 48 challenges are meant to be difficult 50
Coding challenge 50 Tackling a coding challenge problem 52
The problems specific to coding Summary 59
Section 2: Concepts
6
Object-Oriented Programming
Technical requirements 64 What is covariant method overriding in
Java? 107
Understanding OOP concepts 64
What are the main restrictions in
What is an object? 65
terms of working with exceptions in
What is a class? 66
overriding and overloading methods? 109
What is abstraction? 67
How can the superclass overridden
What is encapsulation? 70 method be called from the subclass
What is inheritance? 73 overriding method? 110
What is polymorphism? 75 Can we override or overload the main()
What is association? 79 method? 110
What is aggregation? 81 Can we override a non-static method
What is composition? 83 as static in Java? 110
What are the main differences
Getting to know the SOLID
between interfaces with default
principles 86 methods and abstract classes? 114
What is S? 86 What is the main difference between
What is L? 93 abstract classes and interfaces? 115
What is I? 98 Can we have an abstract class without
What is D? 102 an abstract method? 115
Can we have a class that is both
Popular questions pertaining abstract and final at the same time? 115
to OOP, SOLID, and GOF design
patterns 105
What is method overriding in OOP
(Java)? 105
What is method overloading in OOP
(Java)? 106
