[Java backstage interview] Spring recruits & autumn recruits job hunters interview experience sharing

Java background interview experience sharing

A careful summary based on the personal experience of the Spring and Autumn Recruitment,
including interview questions and interview tips for major companies

Ctrip

1. The difference between jvm thread and operating system thread
2. What are the jvm stacks and heaps
3. What might happen to oom
4. How to troubleshoot oom
5. When the shopping cart is not logged in in the project, where is the product information stored, cookie or session, why choose cooike instead of session
6. Choose product color or package, how to design the table, sku problem

The interview experience is not very good, the interviewer keeps asking you what you don’t understand, and you are not fully prepared

Huawei

1. Receiving is in restful form or url body form
2. Linux Inotify mechanism in the project
3. Fuzzy query
4. How to build the server
5. Mathematical Modeling Contest on Resume
6. Cloud service, cloud computing foundation
7. Is there an actual project manager

Huawei's interviews have always been very random, and the content on the resume has been prepared solidly, especially the projects done by the laboratory, the competitions that they participated in, and the papers sent to the interviewers. Don't be too active.

where to

1. HTTP related knowledge
2. Linux commands, pipes
3. Database index, composite index and cluster index
4. Is Redis single threaded?
5. What are the concurrent packages, what is CountDownLatch, and in what scenarios?
6. Handwriting deformation binary search, tree mirroring

Two sides technical side, one side hr side, I only remember part of the test questions, relatively simple, the first offer in life, thank you~

Xiaomi (one and two sides)

1. Hand tear fast row
2. Shredded non-recursive preorder traversal
3. Hand tear Pow realization
4. Hand tear number n all arranged
5. Which parts of the Redis source code have been seen, and how to do master-slave replication
6. Java memory model
7. The put process of hashMap, how to initialize it, and how to deal with the null value in the first put entry
8. Some characteristics of treeMap and linkedHashMap
9. Which synchronous collections, the realization of concurrentHashMap
10. The difference between the implementation of the blocking queue ArrayListBlockingQueue and LinkedListBlockQueue
11. The role of each module of Java memory
12. Mysql underlying implementation and composite index

For the mastery of the underlying principles, you need to study the source code in depth, and compare and summarize similar data structures

NetEase Hangzhou Research

one side:

1. HashMap, red-black tree linked list query time complexity, is thread safe, how to thread safe
2. What does concurrentHashMap lock,
3. The role of ThreadLocal, what is the internal implementation, and what is stored in the key value
4. Singleton mode, double detection of hungry man, lazy man ddl, volatile function: prevent instruction retake
5. Session sharing issues in the project, if another server is added, hash consistency issues?
6. How to solve the problem of cache and database consistency
7. Mysql isolation level, what is phantom reading, can it be solved? Solved by gap lock
8. What are the database engines, differences and application scenarios
9. Mysql query is very slow, how to troubleshoot slow query, slow_query_log
10. Adding the index is still very slow, how to troubleshoot the
    second side:
11. Linux view port is called by the process
12. Epoll related
13. Dubbo newsletter
14. Adding the cache is still very slow, how to troubleshoot
15. High concurrency, how to preprocess and protect multiple connections
16. A function uses the rpc call of each module to find out the reason for the slowness

Investigate basic knowledge points on one side, and mostly scene questions on the other side, and finally got the offer.

Meituan

one side:

1. A large number of URL crawlers, store the crawled pages, how to deal with it
2. How to calculate hashcode and hash value in Hashmap
3. Redis cluster structure, redis solves the problem of session sharing, how to deal with if a new server is added
4. Redis persistence in two ways, with their own characteristics
5. Database operation deletes the same row of data, the principle of the leftmost prefix
6. Ways to implement threads
7. Understanding of thread safety
8. Java memory model
9. Algorithms 1, 2, 5, and 10 use at least one to form a number, requiring the least number
10. MVCC
11. High concurrency system design ideas, refer to concurrentHashMap
12. Database performance
    Two sides:
13. Hand tear judgment balance search tree
14. The principle of the leftmost prefix of the database
15. Garbage collection
16. How to design the data table
    Three sides:
17. Is it business or technology
18. The project encountered impressive problems and technology precipitation. What have you learned through the project? What are the shortcomings?
19. What books have you read
20. Impressive in high-performance Mysql, redundancy and third normal form, insert a column of data in the table, at this time the database can not be stopped, how to deal with
21. Web page performance is slow, how to troubleshoot, how to improve
22. Why does the app react slower in foreign countries than in China, and analyze the possible reasons
23. AB bucket, 50 red balls, 50 white balls, how to put the ball to touch two buckets randomly, the probability of touching the red ball is high, how to prove the mathematical problem
24. arr[3,5,8,1,-20,9,4,-10], the difference between arr[i]-arr[j] is the largest (simple dynamic programming)
25. Career planning, domain expert? The architect? Project management?
26. How to plan the progress of the project
27. What source code have you seen?

Investigate basic knowledge points on one or two sides, and on three sides mainly examine the breadth of knowledge and career planning. The interviewer is very patient, has a good experience, and is lucky to get an offer.

summary:

The above is the experience from spring recruitment to autumn recruitment. I think that I can understand all the above questions, and the interview is basically no problem.
Spring recruits are very important for finding jobs in autumn recruits. When you have internship experience and project experience from a big factory, the resume of autumn recruits is easier to pass, and if you have decent project experience, it will be easier in the interview. Get the favor of the interviewer.
Even if there is no chance to participate in the summer internship, it is best to participate in the spring recruitment to better exercise yourself. Precisely because of the experience of spring recruits, I feel that I haven't been so nervous in the autumn recruits.

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The answers to the above interview questions are organized into document notes. As well as interviews also compiled some information on some of the manufacturers & interview Zhenti latest 2021 collection (both documenting a small portion of the screenshot) free for everyone to share, in need can click to enter signal: CSDN! Free to share~

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