In my current job I am responsible to interview new candidates for the developer team. Since this is the first time that I am sitting at this side of the table I had to develop my own system of questions that would lead to the informations I need to decide whether someone is suitable for the team or not.

I want to share those questions:

1. Methodology

• What is agile software development? Do you know or have any experiences with the agile principles? What is your opinion about agile team and organizations.
• What is code refactoring? What is it used for? Do you have some best practices how you refactor your code?
• The topic is debugging: How do you handle bugs?
• What is Test-Driven-Development? What is your opinion about TDD? What would you say if I tell you that I do not like TDD at all.
• Do you know design patterns? Did you use them already? What is your favorite one? How do you learn design patterns?
• What is AJAX? How does AJAX work? What is the difference between AJAX and Web2.0?
• Can you handle the words cohesion and seperation of concern?

2. Thinking

• I tell you to learn a new programming language, say Ruby. How do you organize the learning? What will you do first?
• What would you do if I give you 5 million Euro to launch a start up?
• What is the most important thing you want to do within the next two years?
• What is my company, the company you want to work for, doing? How do you figure the underlying technology we’re uisng to do exactly this?
• Which 5 books did you read last?

3. Common chat questions

• Do you like google? What do you like about it?
• What are current innovations in the java ecosystem?
• It is your task to design a database which holds personal data about some million people. What is the significance of data privacy protection?
• How did the internet change techologically during the last 5 years? How does the future look like?

4. Java Questions

• What stands transient for?
• What are annotations? What are they used for? What is your opinion about using annotations?
• What are the principles of programming servlets?
• What is the session scope? Are there other scopes? What are they used to?
• Tell me about the life cycle of a standard java application and a servlet.
• Is it possible to use Multithreading in Servlets? Should you?
• What is the differnce between a stack and a queue?
• What are the technical principles o a hash map?
• What are Generics? How do you use them? What is your opionion about generics?
• Describe the deployment of a Java Application.
• What is JDBC? What is Hibernate? When do you use them?
• Why is the main method static?
• Which impacts does the final modifier have on object references?
• How do you let the JVM execute some code right before the main method is invoked?
• What is reflection, what is introspection?
• What is the basic idea of a java bean?
• How do you optimize the performance of a loop?
• What is the difference of a servlet and an applett? What does they have in common?
• How do you forward a http request from a servlet to a JSP? Which pattern can you realize by doing this?
• What are the priciple of RMI?
• How do you integrate some native C-code to a Java Class?
• What is JUnit and how do you use it?
• Is it possible to realize a Callback mechanism in JAVA?

5. PHP questions

• Tell me about arrays in PHP? What are the principles? What do you not like about arrays in php?
• Can you name some array sorting functions in PHP?
• How do you write multiple variables using echo? What is the fastest way doing that?
• What dou think, is PHP object oriented? Why?
• What is the difference between “1″ and “True”?
• How do you write to the end of a file?
• How do you define constants in PHP classes?
• Is it possible to overload methods in PHP?
• How do you use callback functions in PHP?
• What additional features do you think should a future version of PHP provide?
• What is Zend?
• What is Pear?
• What about type safety in PHP? Any opinions?

6. Logic

• Connect all dots using just 4 lines:
  
• There is a town with two hospitals. One is very big, the other is quite small. On one day the newspaper says: 3 boys and 9 girls were born yesterday. What do you think: Which hospital is more likely to have such rates?

7. Opbject Oriented Principles

• What is the difference between an abstract class and an interface? When do you use the one or the other? What impacts does each have?
• What do you understand by encapsulation?
• What is polymorphism? Can you give me an example?
• What are alternatives to object oriented languages? When do you use them?
• What happens when you instantiate an object?