Java and Android Technical Questionnaire

Java and Android Technical Questionnaire

These are the theoretical questions that will most likely be asked during the project defenses and during the technical part of your job interviews. As you can see, they are separated into two groups.

1. The first group are questions that we expect you know the answer of in great details and could answer and explain additional questions regarding them. These questions are related to the material we have covered during our onsite classes.

2. The second set consists of questions that we expect you to know about and can give a basic answer, without diving deep into the subject. These questions are usually based on additional resources we provide inside the Learning Management System. You should research those topics in your spare time.

The idea of these questions is for them to act like a learning guide and provide the student with an accurate way of measuring their understanding of the key concepts behind each course and module.

Java Language

Questions that you must be able to answer in detail:

* What is Java?

* What is JDK, JRE and JVM?

* What is “import” in Java?

* What is the difference between Array, ArrayList and LinkedList in Java?

* What is the difference between HashMap and TreeMap?

* What is Generic type in Java?

* What is the difference between == and equals()?

* What is the difference between “static” and “final” variables in java?

Questions you should have general knowledge of and should answer in a few words:

* Is Java code managed or unmanaged code?

* What is the role of the JVM?

* What is Ahead-of-time (AOT) compilation and bytecode in Java?

Java Object Orientated Programming

Questions that you must be able to answer in detail:

* What is a class?

* What is an object?

* What are the access modifiers in Java?

* Explain static initializers in Java?

* Explain overloading in Java?

* What is data encapsulation?

* Explain inheritance in Java?

* What is polymorphism in Java?

* Explain overriding in Java?

* What is abstract class and interface and what is the difference between them?

* What is composition?

* What are final classes in Java?

Questions you should have general knowledge of and should answer in a few words:

* What are annotations in Java?

Data Structures and Algorithms

Questions that you must be able to answer in detail:

* What are data structures?

* What is a linear data structure?

* What operations can we perform on data structures?

* Explain what is a linked-list?

* Explain what is a stack?

* Explain what are queues?

* What is algorithm?

* What is algorithm analysis?

* Why do we need to do algorithm analysis?

* What are asymptotic notations?

* What is a recursive function?

* What is linear searching?

* What is binary searching?

* Describe how heaps work. Write some pseudo code

* What is a tree?

* What is post-order, pre-order, in-order traversal?

* What is a binary tree?

* What is a binary search tree?

* What is a graph? Provide practical examples of graphs.

* How does depth-first traversal work?

* Provide a practical example of DFS. Explain it.

* How does breadth-first traversal work?

* Provide a practical example of BFS. Explain it.

* What is hashing?

* Describe how hash tables work. Provide some pseudo code.

Questions you should have general knowledge of and should answer in a few words:

* What is interpolation search?

* Explain divide and conquer algorithms?

* What is dynamic programming?

High-Quality Code

Questions that you must be able to answer in detail:

* What is the purpose of unit tests?

* What other types of testing do you know?

* What makes a unit test high-quality?

* What is SOLID?

* Give a real-life example of Open for extension / closed for modification?

* Give a real-life example of Dependency Injection?

Questions you should have general knowledge of and should answer in a few words:

* How do dependency injection containers work under the hood?

Android and mobile

Questions that you must be able to answer in detail:

* What is Context?

* What is the difference between Activity, Fragment and View?

* What is the lifecycle of Activity?

* What is the difference between .onCreate() and .onStart()?

* What is Intent and when do we use it?

* What is Adapter and why do we need it?

* What is async operation and why do we need it?

* Explain the MVP design pattern?

Spring and web

Questions that you must be able to answer in detail:

* What is Spring?

* What are some of the core modules in Spring?

* What is Java bean?

* What is JDBC and Hibernate and what is the difference?

* What is transaction and why do we use it?

* What is HTTP?

* Which are the main HTTP methods?

* Which are the HTTP response codes?

* What is the format of a HTTP request and response?

* What is REST service?