Social recruitment of Alibaba (new retail department)
Alibaba side (55 minutes)
- Introduce yourself first
- Talk about your own advantages and disadvantages
- Tell me more about the projects I have done before
- What do you think is the biggest challenge in the project?
- Why doesn't Hashmap use a balanced tree?
- Does AQS know? Which ones do you know? Talk about it.
- How does CLH synchronization queue achieve unfairness and fairness?
- The difference between ReetrantLock and synchronized
- Talk about the memory structure of JVM
- When a new object in the JVM is used, will the heap be preempted? How do you design the thread safety of the JVM heap?
- Talk about the data structure of redis
- Redis cache synchronization problem
- Talk about the index structure of MySQL
- Do you have any questions for me?
- Tell me directly orally: Good answer, let's get ready
Two Sides of Alibaba (45 minutes)
- Asked some detailed questions based on the project
- Talk about the data structure of HashMap
- What is the difference between a red-black tree and an AVL tree?
- How can I get a thread-safe HashMap?
- Talk about JVM commonly used garbage collector
- redis distributed lock
- Describe your previous project again
- What do you think is the highlight of this project?
- Which paradigm does your database follow?
- Do you have any questions?
Three sides of Alibaba (50 minutes)
- Talk about the project again
- In the case of a large amount of concurrency in a project, how can we ensure data consistency?
- Why does elasticsearch search fast, and what is its underlying data structure?
- JVM memory model
- Which middleware and frameworks is netty used in?
- Thread pool parameters
- Talk about the difference between B tree and B+ tree
- Why use redis for caching?
- Know Springboot? Let's talk about the startup process of Springboot
- How to solve the problem of bean's circular dependency?
- What queues does Java have?
- Talk about the difference between Spring and Springboot
- What books have you read recently? why?
- How do you usually learn Java?
Introducing Alibaba (Alibaba's reputation)
5 offers (3 rounds of technical side + director side + HR side)
Alibaba side (38 minutes)-introduce yourself
- Introduce the project, be specific
- Talk about the implementation of Redis distributed lock
- Do you understand HashMap? Talk about the put method process
- Is HashMap thread safe?
- How does ConcurrentHashMap ensure thread safety?
- Do you understand database indexes? Talk about
- Common sorting algorithms
- TCP handshake three times and waved four times.
- In-depth questions about optimistic locking, pessimistic locking and their implementation.
Two Sides of Alibaba (45 minutes)
- Self introduction + project introduction
- What role do you play in the project?
- What do you think is your advantage over others? Did you use something that no one else did?
- How does Java load classes?
- What are the commonly used linux commands?
- Spring的IOC, AOP。
- Talk about the ORM framework Hibernate
- Do you understand design patterns? Talk about
- How to design a two-stage submission by yourself?
- What else do you want to ask?
Three sides of Alibaba (30 minutes)
- Tell me about the project I made
- Asked some project-related questions
- The difference between wait() and sleep()
- The realization principle of atomic variables
- The CAS problem, talk about the solution.
- Is there a better counter solution strategy
- Talk about the difference between NIO and BIO
- How does Nginx determine that a node is down during load balancing?
- Talk about the data types and usage scenarios of redis
- What is the storage method of k8s?
- What is the principle of Spring AOP? how to use? What is the cut point and what is the cut surface? It is best to give an example
- Algorithm question: Give an array of a pile of coins and return all combinations
Alibaba director face (34 minutes)
- Algorithm: Print out all subsets for a set; multithreading reads data from multiple files and writes to the same file; judges whether the ip is within a given range; scrambles a deck of playing cards and cannot use extra space, Prove why it is random.
- The difference between Tcp and udp
- The principle of thread pool and the application scenarios of various thread pools
- The difference between using a limited blocking queue and an infinite blocking queue in a thread pool
- What if you find that your sql statement always goes to another index, but you want it to go to the index you want?
- mysql execution plan
- Why use b+ tree for database index?
- What are the main aspects of sql optimization you are doing, and what methods and tools do you use?
- Any questions?
Alibaba HR noodles (23 minutes)
- Self introduction
- How do you usually study?
- Do you have any hobbies?
- What do you think of 996?
- How to balance work and study?
- Do you have anything to ask
to sum up
When interviewing the new retail department during social recruitment, it was mainly because of insufficient preparation and tight interviews, so the performance was not very good. After three aspects, there was no follow-up. Later, I realized the importance of learning, and I usually took more time to study. Later, I was lucky to get the qualification for referral. In order to seize this opportunity, I made a lot of preparations, and fortunately I had already got the offer.
This interview comes from the interview experience of a colleague before me
In the season of gold three silver four job hopping, the younger brother prepared two interview books for the older brothers:
- One is technical dry goods "Java core knowledge points finishing"
- A part is the interview Zhenti "1000 Internet Java Engineer interview questions."
Java core knowledge points
1000 Internet Java Engineer Interview Questions