Tuesday, 04 July 2017

Whether you are running a large enterprise and trying to find the right Java or Open Source professional, or you have upcoming interviews for a new job, knowing which questions to ask and the right answer to them is a real task.

Here are the 20 most commonly asked interview questions, along with some helpful guidance, straight from our experienced consultants.

1. Tell me about yourself.

This one seems like an easy interview question as it is open-ended. However, what the hiring manager is looking for is a snapshot of who you are, why you are the right person, and why they should vote to have you around the office.

2. What skills make you perfect for this specific project/role?

Roles in the Java and open source area very often tend to be recruited for on a contractual basis. Therefore, it is always helpful to get to grips on the size, scope and industries that the company’s projects are working within. You should relate this to any relevant experience or skills that you may have and back this up with certifications or examples. Simply, there is a shortage in resources within that team and you need to fill it.

3. What are your biggest weaknesses?

In the Java and open source landscape, it Is not only technical skills that will win you the job- attention to detail and soft skills are essential. After all, every developer knows the impact of a misplaced semi solon. By telling your interviewer about examples of when you may have stayed late to ensure a task was finished properly, or other moments of sheer perfectionism, you will stand out in their mind. The key is to minimise your weaknesses by giving examples of how you overcame them and turned them into qualities.

4. Where do you see yourself in five years’ time?

The interview wants to see how ambitious you are and ensure that this isn’t a short term position. If you’re going for a relatively junior position, explain how you would like to see your career progress e.g. ‘I would like to manage a team of people and progress to Senior Java Developer’. If you are applying for a senior position, explain how you would like to move the company forward. You can gather ideas on this by looking at their strategy and objectives.

5. What is an immutable object? Can you write one?

Immutable classes are Java classes whose objects cannot be modified once created. Any modification in an immutable object results in a new object. For example, ‘is String immutable in Java?’

6. What are the important features of the Java 8 release?

Java versions are always a frequent topic of discussion in interviews so it if important to keep up-to-date with what is happening and what the benefits of implementing the new version are. Here are some of the important features:

  • Interface changes with default and static methods
  • Functional interfaces and Lambda Expressions
  • Java Stream API for collection classes
  • Java Date Time API

We strongly recommend going through the above list and understanding each point.

7. Describe a typical week in your current role?

Relating your previous experiences to the role that you are applying for is vital. It not only highlights skills that you already have, but also tells the interviewer about your workload and your ability to stay organised and in control.

8. What makes you a great fit with our team?

Although there is a high degree of remote working in many jobs within the industry, naturally leading to little contact with colleagues, consultation often requires emotional intelligence and soft skills. You need to have the ability to understand the client’s requirements and convey ideas and solutions clearly.

9. Why are you looking to leave you current employer?

Unless you have been lucky enough to be headhunted, employers will want to know why you are looking to move on because they are sceptical about a number of reasons why you were unhappy or not right for your previous role. This subject should be approached with caution as you do not want the interviewer to feel that you will encounter similar issues with them in the coming years. Possible reasons could be to say you are looking for better opportunities, for you to grow professionally, or you were looking for the chance to work abroad.

10. What is JVM and is it platform independent?

Java Virtual Machine (JVM) is the heart of java programming language. JVM is responsible for converting byte code into machine readable code and not platform independent. That is why there is different JVM for different operating systems. JVM is customisable with Java Options such as allocating maximum and minimum memory to JVM.

11. What is the difference between processes and threads?

A process is an execution of a programme, while Thread is a single execution sequence within a process. A process can contain multiple threads. A Thread is sometimes called a lightweight process.

12.   What can we expect to see from you in your first 90 days here?

Employers will have expectations for you. If you are asked, follow this general response:

  • You’ll work to determine how your job creates value. You won’t stay busy doing anything, but will figure out what are the most helpful things to be doing.
  • You will learn how to be helpful to your team, your peers, customers, suppliers, vendors and, most importantly, your boss, all while bringing enthusiasm and a sense of teamwork to the workplace.
  • You will play to your strengths- if you are hired, it is because you have certain skills, and you will apply these skills to make things happen.
  • Finally, apply specific details that are applicable to the role and what you can provide
13. What is your biggest achievement in your previous projects?

Ideally, this answer should combine both technical and soft skills e.g. you may have guided a team to implement your proposed solution and, as a result, solved the issue.

14. What are some of the best practices relating to the Java Collection framework?

  • Based on the application’s needs, choosing the right type of the collection to use, is very crucial for its performance. For example, if the size of the elements is fixed and know a priori, you should use an Array, instead of an ArrayList.
  • Some collection classes allow us to specify their initial capacity. Thus, we can use it to avoid resizing or rehashing, if we have an estimation on the number of elements that will be stored.
  • By using Generics, you avoid the ClassCastException during runtime. Always use Generics for type-safety, robustness, and readability.
  • In order to avoid the implementation of the hashCode and equals methods for our custom class, use immutable classes provided by the Java Development Kit (JDK) as a key in a map.
  • Programme in terms of interface, not implementation
  • As opposed to returning a null, return zero-length collections or arrays, in case the underlying collection is empty.
15. What are your salary expectations?

This question is raised in almost every interview, regardless of the industry, so when you are making your preparations, have this question in mind.

The best approach is to look at the average salary for someone in the industry, geographical area, and those with the same skills as you. This should give a basic idea of reasonable figures. Don’t be tempted to sell yourself short so, if you are not sure; take a look at average salary checkers.

The right answer is broad, but realistic e.g. “I’m looking for a starting salary somewhere between £25,000 and £30,000.” While the wrong answer would be to say, “I’m not sure. How much are you on?”

16. When is garbage collection used, and what is the purpose of it in Java?

The purpose is to identify and discard the objects that are no longer needed by the application, so that the resources can be reclaimed and reused.

17. Why do you want to work for us?

The interviewer will hope that know about the company culture, and whether you can relate to the business’ values and vision. Every organisation has its strong points, and you should highlight these in your answer. For example, if they emphasise a fun environment, mention that you would like to be in the team because you are fun-loving and bubbly yourself.

18. How will you motivate your team?

Regardless of your position in the company, many have flat hierarchies which involve managing from above and below. Having examples of when you have motivated and led a team will help you to excel in the interview room.

19. What challenges are you looking for in this position?

The best way to answer questions like this is to discuss how you would like to utilise your skills and experience more than you have done previously. You can mention that you are motivated by challenges, can effectively meet them, and have the flexibility and skills to handle the job.

20. Do you have any questions?

Around 75% of job seekers will say “No, I think that’s everything” to this question, which is a terrible response in ensuring that you stay in the mind of the hiring manager. This question gives you an opportunity to clarify any areas of doubt that the interviewer may have about you, ensure that you have understood everything clearly. Here are a few examples of questions to ask

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