There were multiple technical rounds. The rounds went as below:

• 2 Written Tests (one online, one in the company)
• 2 Technical Interviews
• 1 Director Round

The online written test had two sections. The first section had questions from Operating Systems. The second section had core Java questions.

Personal Interview Rounds: The interview was based on my solution provided for the written round. The main questions mostly covered three areas: 'Data Structures', 'Algorithms', and 'Multithreading'.

They want a candidate who can stay for a longer period of time (like for 5 years and more).

Bracket balance checking.

Input is a string like "AAAAABBCCAA" and it should print "5A2B2C2A". 5 is the continuous number of occurrences for character 'A'. The same applies to other characters.

Input is an array of numbers [1,2,3,4,2,3,1,2], and we need to print the longest increasing sequence length. Here, it should be 4 (for 1,2,3,4).

Implement BlockingQueue for enqueue and dequeue functionality.

Write a scenario where a deadlock is sure to happen.

Tell me what design patterns you would use to implement an elevator calling system.

What are the conditions for using an ArrayList and a LinkedList?

Are you okay to go to other places?

Since my domain was telecom OSS, they asked me to design a device sync module with certain conditions.