Here’s a curated list of top 100 Kotlin interview questions for a senior developer role:
Basics of Kotlin
1. What is Kotlin?
2. Explain Kotlin’s origin and purpose.
3. How is Kotlin interoperable with Java?
4. Mention some key features of Kotlin.
5. What are the advantages of using Kotlin over Java?
6. What are Kotlin’s target platforms?
7. Describe the basic syntax differences between Kotlin and Java.
8. Explain the concept of null safety in Kotlin.
9. How does Kotlin handle nullability?
10. What are the different types of null checks available in Kotlin?
Language Fundamentals
11. Define variables and constants in Kotlin.
12. Explain type inference in Kotlin.
13. How does Kotlin support immutability?
14. Discuss the visibility modifiers in Kotlin.
15. Differentiate between val and var in Kotlin.
16. Explain string interpolation in Kotlin.
17. What are the range expressions in Kotlin?
18. Discuss the significance of the when expression in Kotlin.
19. Explain the usage of Kotlin’s if expression.
20. Describe how Kotlin handles control flow statements.
Functions and Lambdas
21. Define functions in Kotlin.
22. What are default arguments in Kotlin functions?
23. Explain named arguments in Kotlin functions.
24. Discuss the concept of higher-order functions in Kotlin.
25. How are lambdas represented in Kotlin?
26. What is a function literal in Kotlin?
27. Explain function references in Kotlin.
28. Discuss Kotlin’s support for inline functions.
29. How does Kotlin handle recursion?
30. Explain the tailrec keyword in Kotlin.
Object-Oriented Programming
31. Discuss classes and objects in Kotlin.
32. What is a primary constructor in Kotlin?
33. Explain secondary constructors in Kotlin.
34. Discuss the visibility modifiers applicable to classes and members in Kotlin.
35. How does Kotlin support inheritance?
36. Explain Kotlin’s approach to method overriding.
37. What is a data class in Kotlin?
38. Discuss sealed classes in Kotlin.
39. How does Kotlin support delegation?
40. Explain the concept of companion objects in Kotlin.
Collections and Data Manipulation
41. What are the different types of collections available in Kotlin?
42. Explain the usage of immutable collections in Kotlin.
43. Discuss Kotlin’s approach to mutable collections.
44. How does Kotlin support filtering and mapping operations on collections?
45. Explain the concept of sequences in Kotlin.
46. What are the standard library functions available for collections manipulation in Kotlin?
47. How does Kotlin handle transformations and aggregations on collections?
48. Discuss the significance of the groupBy function in Kotlin.
49. Explain the usage of the partition function in Kotlin.
50. Discuss Kotlin’s approach to sorting collections.
Coroutines and Asynchronous Programming
51. What are coroutines in Kotlin?
52. Explain the benefits of using coroutines for asynchronous programming.
53. How does Kotlin handle suspending functions?
54. Discuss the different coroutine builders available in Kotlin.
55. What is the CoroutineScope in Kotlin?
56. Explain the concept of structured concurrency in Kotlin.
57. Discuss Kotlin’s approach to cancellation and timeouts in coroutines.
58. How does Kotlin handle exception propagation in coroutines?
59. Explain coroutine context and dispatchers in Kotlin.
60. Discuss Kotlin’s support for reactive programming with coroutines.
Concurrency and Multithreading
61. What are threads in Kotlin?
62. Explain Kotlin’s approach to thread creation and management.
63. Discuss synchronization mechanisms available in Kotlin.
64. What are the challenges of concurrent programming, and how does Kotlin address them?
65. Explain Kotlin’s support for thread-local data.
66. Discuss Kotlin’s approach to thread safety.
67. What is the difference between concurrency and parallelism in Kotlin?
68. Explain Kotlin’s support for atomic operations.
69. Discuss Kotlin’s approach to deadlock prevention.
70. How does Kotlin handle thread interruption?
Error Handling and Exception
71. What is an exception in Kotlin?
72. Explain Kotlin’s approach to exception handling.
73. Discuss the hierarchy of exception classes in Kotlin.
74. What are checked and unchecked exceptions in Kotlin?
75. Explain the usage of the try, catch, and finally blocks in Kotlin.
76. Discuss the concept of custom exceptions in Kotlin.
77. How does Kotlin handle exception propagation?
78. Explain Kotlin’s approach to resource management in exception handling.
79. What is the Nothing type in Kotlin, and how is it used in exception handling?
80. Discuss best practices for exception handling in Kotlin.
File I/O and Serialization
81. How does Kotlin support file I/O operations?
82. Explain the usage of input and output streams in Kotlin.
83. Discuss Kotlin’s approach to reading and writing files.
84. What are the different file manipulation functions available in Kotlin?
85. Explain Kotlin’s support for file path operations.
86. Discuss serialization and deserialization in Kotlin.
87. How does Kotlin support JSON serialization and deserialization?
88. Explain the usage of the Serializable interface in Kotlin.
89. Discuss Kotlin’s approach to customizing serialization.
90. What are some third-party libraries available for serialization in Kotlin?
Unit Testing and Quality Assurance
91. How does Kotlin support unit testing?
92. Discuss the different testing frameworks available for Kotlin.
93. Explain the usage of assertions in Kotlin tests.
94. Discuss the concept of test fixtures in Kotlin.
95. What are some best practices for writing unit tests in Kotlin?
96. Explain Kotlin’s approach to mocking dependencies in tests.
97. Discuss integration testing in Kotlin applications.
98. How does Kotlin support code coverage analysis?
99. Explain the concept of test-driven development (TDD) in Kotlin.
100. What are some common testing anti-patterns, and how can they be avoided in Kotlin?
These questions should provide a comprehensive coverage of various aspects of Kotlin programming language, its features, and its applications.
