3 Technical rounds, 1 Managerial round I interviewed for Walmart Labs. The process was very smooth and had 3 technical rounds consists of the following, 1st Round Data Structure The interviewer was good and touched upon the Linked list, arrays, and string questions. First, he asked me to introduce myself and have a discussion on my project and previous organization. Then he asked me to write a program to Add 2 linked list. Next, he moves on to the String question and asked me to write and program to print the first occurred element and having 3 frequency. 2nd Round - JAVA He focused more on multi-threading and seems like he is not interested in listening to all the approaches, he was focusing more on per defined approach which he made up in his mind. He asked me the following questions, 1. Write your own Blocking Queue(Producer consumer problem) 2. Concurrent hash map internals 3. He asked some questions on the future, callable, and thread executor. 4. Asked me to write code for making a class immutable. 5. Few java collection related questions 3rd Round Java and problem solving The interviewer was quite serious and was not willing to help at all if I stuck somewhere. First, he asked me to write a program to balance the brackets and asked me to execute the program. Once this was completed he moved to java questions and asked me the following questions, 1. What is special about Strings in java. How String pool works. 2. Write a program for singleton class, he was more focusing on the thread-safe approach. 3. Comparable vs comparator 4. wait vs sleep in threads 5. Blocking queue working 6. He asked to write the SQL query, I didn't remember the exact question, as I am from the NoSQL background. 7. Indexing in the database. 8. Asked me to write a program for reversing a linked list. 4th Managerial round He was cool guy started the interview with a greeting, Post that he asked to draw the architecture diagram for the project on which I was working in the last organization. He asked a few questions on that, post that he moved to the design questions, where he asked me to design HTML file parser and few questions on the other design pattern too. Lastly, he explained to me about the team which I will be joining.