Scala Interview Questions

Scala Interview Questions

1. What is Scala?
Scala is a Java-based, hybrid, an object functional programming and scripting language for the general software applications which is designed to express solutions in a concise manner.

2. What tuples are used in scala?
The tuples in Scala combine a fixed number of items together so that they can be passed around as a whole. A tuple is immutable which can hold objects with different types, unlike an array or list.

3. What are Streams in Scala.
Stream is a Lazy list which evaluates the elements only when it needs to. This type of lazy computation enhances the Performance of the program.

4. What are Higher-order functions?
A Higher-order function is a function which takes one or more Functions as Arguments or returns a Function as its result.

5. What are scala maps?
Scala maps are a group of unique value (Key) pairs. Maps are also referred as hash tables and they are categorized as mutable and immutable. The difference between mutable and immutable is that an immutable object cannot be changed by itself.

6. Explain what are option, some and none in scala?
‘Option’ is a Scala generic type which can either be ‘some’ generic value or none. ‘Queue’ often uses it to represent primitives that may be null.

7. What are scala variables?
Variables are the reserved memory location used to store values. When you create a variable, based on the data type of the variable, the compiler allocates memory for it. reserved.

8. What is the difference between Class and an Object?
Class combines the data and its methods whereas the Object is one particular Instance in a class.

9. What is the advantage of Scala?
The advantages of Scala are :
Scala is less error prone functional style
It has high scalability
It needs high maintainability and give high productivity
It has high testability
It provides features of concurrent programming

10. What is the importance of App in Scala?
A helper class, named App, is provided by Scala which provides the main method and its members together. App trait allows the Objects to be turned into executable programs faster. The App class in Scala can be extended instead of writing your own main method. This makes you produce concise and scalable applications.