Getting a job at Amazon is a dream for many programmers. It’s a top IT company that offers high pay and great opportunities for growth. You are expected to work hard during the interview if you want to get your dream job at Amazon. It is always better to prepare answers for Amazon Java programming interview questions by yourself.
To get a job at Amazon, you are required to have a basic understanding of object-oriented programming (OOP). As the name suggests, OOP is all about objects. Objects are data structures that behave as real-life things do. They can be acted upon, and they react in their ways.
While preparing for Amazon Java interview questions, make sure to look for sample code on the Internet or from your friends who work at Amazon already. You never know when a problem would pop up on screen asking you to write some code yourself. You should know how to solve such problems as it will catch the attention of your employer.
15 Most Common Java Questions Ask In Amazon Interview With Answers
Question 1 – What is the interface in java?
Answer: Interface defines a contract with information about required methods, functions.
Question 2 – Difference between an abstract class and an interface in Java?
- Abstract Class – A class that can have only one instance and cannot be instantiated directly.
- Interface – Must have a default implementation of all specified methods, and they are implicitly abstract methods. Can be declared as public or private or protected.
Question 3 – What is jargon used in the Java programming language?
Answer: Constructor, Destructor, static, transient, final variables, etc., are some jargon used in the Java programming language.
Question 4 – Explain how the concepts of abstraction and encapsulation apply to Java classes?
- Abstraction – A notion that represents a concept window.
- Encapsulation – Combines data & functions in such a way that it provides the user of that class with a limited set of operations on its specific attributes via its public interface, i.e., getters & setters for each variable or property accessible by client code.
Question 5 – What is Inheritance?
Answer: Inheritance defines the relationship/usage between two objects when one object acquires all functionality implemented by another object(s); it’s called inheritance.
For example, java Swing implements ActionListener, so every single listener extends Abstract.
Question 6 – What is Abstraction?
Answer: Abstraction defines the usage of an object without knowledge of its implementation. For example, the java print() method can be used w/o knowing how to implement a Printable interface.
Question 7 – What are Interfaces? Give an example.
Answer: Interfaces define a contract between two classes that shows like “I am implementing this interface.” So, any class which implements an interface must obey the rules defined by that interface (the protocol).
If these rules are not followed, then it throws an error as a compilation failure.
Example: Car implements the interface of Runnable; that is why you can pass a Car instance into another class which requires its arguments to be implemented by Runnable interface.
Question 8 – What happens when you try to access a missing field in Java?
Answer: You will get an error if you are not inside a synchronized block, and it’s throwing a NullPointerException if you are inside one. This could be due to 2 reasons: 1) If the variable has been declared as private or protected 2) The compiler cannot find the field during compilation.
Question 9 – Why are Interfaces necessary?
Answer: They are helpful when we want to achieve inheritance but not the actual implementation of methods. They can also be used when we have to write an application that uses multiple sets of Objects that are unrelated.
Question 10 – How do you access a private method or variable from the same class?
Answer: Private members can be accessed through getter and setter methods only, but not directly. In this manner, subclasses can also access protected members, but they cannot modify them directly.
You may create appropriate setter and getter methods for each private member to make it accessible privately as well as publicly within your application or classes.
Question 11- What is Singleton Class?
Answer: A “Singleton” Class is used to ensure that only one particular class object can exist at any given point in time. It’s a mechanism used for storing unique data in Java applications. The Singleton pattern generally involves the use of static methods or variables to store state information that would otherwise be shared among all objects.
Question 12- What is an important feature in Java?
Answer: A class declaration is the first statement in a Java program. Classes can contain fields, method definitions, constructors, and destructors. The class declaration begins with the keyword “class”, followed by the name of the class, followed by a parameter list for that particular type of object (for example String or int), followed by an opening brace, and finally ends with a semicolon.
Question 13 – What is the purpose of a class? And what is the difference between a class and an object in Java?
Answer: Class provides a template for making objects. Since classes provide templates for creating objects, classes are also called blueprints or schema for objects. Each object has variable data associated with it (like name, age) that are created/allocated when an object is created. The contents of the data members are saved in memory used by the OS as required by JVM.
Question 14 – What is a lambda expression?
Answer: Lambda expressions are used in place of anonymous classes. They only contain one line of code that needs to be executed ( in Java 8 ) and hence reduces the amount of code required for Anonymous class implementation. Also, they can be created with a more concise syntax than traditional anonymous inner classes.
Question 15 – What is the difference between static and non-static variables?
Answer: A static variable is a value that remains constant throughout the life of the program. Non-static variables, on the other hand, are instances of mutable data. Non-Static or Instance Variables are bound to an Object, while Static ones make no such restriction.
How To Prepare Well For Cracking Amazon Java Interview?
Prepare well for your interview by taking Amazon Java Interview questions. If you read all the interview questions from our site, you will have a strong idea about them. You need to be confident in what you know and should be able to answer any question confidently. Take help from books too. They are a good source of helping hands during the interview time.
Just study this carefully and keep practicing more problems! I would recommend solving at least 10-15 Amazon interview questions a day in a clockwise manner. This will help you to remember the concepts better.
Also, solve each question at least three times before moving on to another question. Sometimes the same question could be tricky; it can be simple, understanding is most important in terms of practicing.
Solving Questions from various collections about everyday topics like Collections, Data Structures, OOPS Concepts, etc., will help you.
I would recommend practicing as many possible interview-related questions ( not only Amazon but all ) because it will help you in gaining confidence for your interviews.
Amazon Interview Process
Online coding test. You will be given 15 minutes to solve 4 – 6 problems using either C++, Java, or Python (You need not know any of them as long as you can code in it)
Telephonic Round interview consisting of 5- 7 Technical and HR questions. Mostly Behavioral-based questions with some easy technical questions. Most candidates are cleared in this round itself.
Some people who clear both these rounds will have to attend an offer presentation session, and they are given their salaries after that session before making a final decision if they want to accept the job offer or not.
In this round, you will have to solve an algorithmic programming problem in C++, Java, or Python. The time allocated for this will be around one hour, and the issues themselves are complex enough that even if you know any of these languages, it will take a lot of thinking to crack them.
In this round, the task is to write an algorithm (any) for a problem that you are given. For the technical part, they check if you can analyze algorithms, communication skills, question answering ability, thinking ability, etc.
You will be shown two pictures and asked ten questions about them. It’s not extremely difficult, but some questions require prior knowledge of languages or some kind of common-sense judgment from the candidate.
Finally, there is a written test in which they check your basic knowledge on data structure, operating systems (OS), programming language paradigms like functional programming, object-oriented programming, etc. The syllabus is very general because it covers both Computer Science & Information Technology.
Tips For Cracking Amazon Interviews
- Amazon is very particular about time. They would have a specific schedule, and they want you to finish everything on time without wasting any second. To do that, you need to practice with some sample questions.
- Once again, it’s essential to show your passion for computer science. Don’t go too overboard, like mentioning coding in your daily activities & hobbies section, or the reason why you applied for this position was just that you’re a big fan of Jeff Bezos. 3) Don’t oversell yourself. Be modest and sincere.
- Prepare your answer for the question “Why Amazon?”. It’s not a silly question; just think about it. Why do you want to work at Amazon?
- Why do you want to be a software engineer at Amazon? Why do you want to have this position? What will you improve if you get that position? How can your professional experience help the most in a company like Amazon, which is already doing very well? Don’t just ask yourself these questions – actually prepare an answer for each question. Practice it multiple times!
- If you are applying from outside the US: be sure that your resume is written in English and formatted correctly! Also, having some international experience shows your adaptability & communication skills as well as cultural sensitivity (very important). Employers notice those things.
- Besides having a solid technical background, employers are looking for creative, fun & enthusiastic employees. They want passionate individuals (who enjoy what they do and enjoy helping others).
- Employers also look for cultural fit. The technical skills alone may not overcome social/cultural differences. For example, if you are applying from outside the US, you should be very clear about your communication style in your cover letter and when asked about it in interviews.
- Most of the time, a potential employer assumes that you will be like them. If you are not, this can be a severe issue for your candidacy. Make sure to check the company website before your interview and prepare your answers accordingly.
- Also, look at previous interviews on Glassdoor or Indeed, to see what questions they might ask you. For example, some companies may ask about other potential jobs (in case of relocation); others may ask you if you have any specific requirements for work schedule, etc.
- Last but not least, dress well and stay confident!
How Long is the Amazon Interview Process?
The process to get hired at Amazon is very lengthy but the time taken can differ based on the job role.
For most of the Amazon jobs, it takes about 2 to 3 months, while for technical roles like Software Development Engineer (SDE), System Design Engineer, and Product Manager. It takes longer.
Many of the candidates who have worked in Amazon said that to get hired by this company, you need to be “patient” and should not give up easily because ultimately, it’s worth being hired at Amazon. If it’s your dream job, then give it all you’ve got.
The selection process at Amazon is lengthy. It’s made for identifying the potential candidates and not filtering out people with technical ignorance. So if you are ready to change your location at any given time, travel long distances and settle in distant cities away from your family, and have no problem getting up every day at 3 am, then you should be selected as an employee of Amazon.
What’s After the Amazon Interview?
Once you clear the interview, you will have to undergo a personality test and then a basic IQ test. Once you clear these, your final online aptitude test awaits.
After you clear this aptitude test and are selected, a background check will be conducted to make sure that you do not have any criminal records.
The further rounds of interviews involve multiple interview sessions with different teams like tech, design, and HR for technical jobs. You might also be asked to build something or solve a problem in whiteboard interviews. Finally, if you pass everything, then Amazon would call you for an on-site visit where they take up new employees.
You can see more details on what’s involved in your specific job role at http://www.amazon.jobs/en/work-at-amazon
Who doesn’t want to start their financial life working at Amazon.com? The company gives so many opportunities to its employees. Remember that you should not give up! Just try your best, and everything will work out alright. Keep practicing, and never lose your hope!
Frequently Asked Questions
- Is cracking Amazon Interview tough?
Answer – Yes, it is tough! But not impossible. If you find your Interview challenging and aren’t able to crack the Amazon interview after several attempts, know that everyone goes through this phase. Also, keep in mind that your external environment might be hindering you from performing well in the interview. Hence, make sure your surroundings are conducive to cracking Amazon interviews.
- What if I miss an answer?
Answer – Don’t panic! Amazon recruiters don’t expect perfect answers from you; they are ready to accept any type of response from you as long as it’s logical and conveys what you want to say regarding the question asked.
Hence, if you were not able to answer a question or felt that what you answered was not apt, ask them the same. It is always better to know your shortcomings and make sure you work on them before moving forward in the process.
- Does academic performance matter in Amazon Interview?
Answer- Not really. At times, we have had people with very poor academics cracking the interview. The key is, to be honest about your academic performance and work on improving it before you start the process of picking up a job at Amazon.
- How to dress for an Amazon Interview?
Answer- The dress code for Amazon is Casual- Comfort comes first. You can wear jeans, T-shirts, or anything that makes you feel comfortable during the interview.
- Should I contact HR after a Job Interview at Amazon?
No, you should just wait for their call and never try to chase them for an answer via email or phone calls.