The autumn recruitment is over. I started to review in mid-May, and I started to submit resumes in July. I will keep a brief record until now. Today I will share with you the interview experience of a friend of mine who was lucky enough to get an Ali offer. The epidemic has just improved. I believe there are still many friends who work online, and I have nothing to do. I asked some real questions from my friend Ali's interview and some real questions I compiled to share with you.
Here are the latest BAT interview questions, the new version of the 2020 ship! ! Friends in need can: click here! ! Code CSDN! . I hope that those in need can find a satisfactory job in the first wave of recruitment this year!
Ali side (60 minutes): The speed is very fast, basically covering all common test sites
- Project situation, redis, message middleware, data consistency, distributed session, way to realize distributed session (except for redis third party), login process
- Redis function, delete strategy, cluster, cache breakdown
- Circular dependency of spring, life cycle of spring bean, transaction propagation level
- Introduce common collections, Arrayslist, hashmap, hashset, etc.
- Common concurrent packages
- What are the common sorts, talk about Hill sorting, why is it fast?
- Introduce the red-black tree, the characteristics of the red-black tree, how to rotate the red-black tree
- mysql, index structure B+ tree, hash index, how to solve slow query, under what circumstances can not use index, the execution flow of sql statement, the realization of covering index
- Virtual machine, class loading mechanism, garbage collector, cms, ps usage scenarios
- Int integer difference (memory location)
- Computer network handshake three times, waved four times, at which stage is the ddos attack
- I added a written test that night: 1. Given a string, please arrange the characters in the string in descending order of frequency. 2. The longest non-repeated string is easy to write in half an hour
Ali on the second side (70 minutes): I had a good chat with the interviewer, especially at the end, I talked about learning methods, life, I can talk too much
- Five-layer, seven-layer protocol of computer network
- The difference between udp/tcp, which one does WeChat use
- Introducing Quick Sort
- I can’t remember when I’m finished (all basic knowledge, all answered) very simple
- How do you usually study?
Ali three sides (about 35 minutes): I just chatted and gave it on the spot, telling me to prepare for the follow-up interview
- Self introduction, project introduction
- Distributed session, how does redis improve the access rate
- Security md5 encryption process
- Talk about redis (introduced single thread, multiplexing, master-slave mode, sentry mode, cluster mode, rdb, aof persistence process)
- Introduce quick sort, analyze time complexity, how to improve?
Ali on all sides (40 minutes)
- career planning
- Do you have any suggestions for subsequent versions of java?
- If it is you, how do you design a garbage collector and how to reduce fullGC time
- A piece of article, I want to hash it to a piece of space, what can be saved and decrypted with fingerprints, how do you design it?
Knowledge to be prepared The
following are some of the most impressive questions in recent interviews, so they don’t belong to the company, because they don’t make much sense. They are roughly classified and recorded. At present, I only think of so many, but you must know that these questions are just the tip of the iceberg, even if they will. Nothing can be done, the most important thing is a solid foundation and a clear mind.
Speaking of this, I have compiled a "Java Interview Summary Summary" for everyone, including Java basic knowledge, collection containers, concurrent programming, JVM, commonly used open source framework Spring, MyBatis, database, middleware, etc., including as a Java Most of the knowledge that an engineer needs or may use in an interview.
If you need this full version of the interview notes, three-link support, you can get the information for free-after three-link (commitment: 100% free) Quick start channel: Click here for the secret code CSDN! It
is not easy to organize, friends who feel helpful can Help, like, share and support~ Your support, my motivation; I wish you all a bright future and constant offers! ! !
Architecture design interview questions:
1. Please list several commonly used design patterns in JDK?
2. What are design patterns? Have you used any design patterns in your code?
3. Static proxy. JDK dynamic agent and CGUB dynamic agent
4, static agent
5, dynamic agent
6, cglib agent
7, singleton mode
8, factory mode
9, observer mode
10, decorator mode
11, spike system design
12, distributed
13. Distributed overview
14, distributed
15, cluster
16, microservices
17, multi-threaded
18, high concurrency
19, distributed system design concept
20, distributed system goals and elements
21, distributed system design two major ideas: Centralization and decentralization
22, what is the difference between distributed and cluster?
23, CAP theorem
24, proof of CAP theorem
25, BASE theory
26, core ideas
of BASE theory 27, three elements of BASE theory
28, 1. Basically available
29, 2. Soft state
30, 3. End-of-quantity consistency
31, Data structure and algorithm
32, Bubble sort
33, Selection sort
34, Quick sort
35. Recursive
36. Binary search
37. Consistent Hash algorithm
Java basic knowledge interview questions:
1. Does Java have goto
2. What is the use of
final ? 3. The difference between final finally finalize
4. This keyword usage
5. Super keyword The usage of
6, the difference between this and super
7, the main meaning
of static 8, the uniqueness of
static 9, static application scenarios
10, static notes
11, process control statements
12, the difference and function of break, continue, return
13 , In Java, how to break out of the current multiple nested loop
14, object-oriented
15, object-oriented overview
16, object-oriented and process-oriented difference
17, object-oriented three characteristics
18, object-oriented features
19, what Is the mechanism of polymorphism? How does the Java language implement polymorphism?
20. What are the five basic principles of object-oriented (optional)
21. Comparison of abstract classes and interfaces
22. What are the differences between ordinary classes and abstract classes?
23. Abstract classes Can I use final modification?
Spring interview questions (2020 latest version)
1. What are the design goals, design concepts, and core of the Spring framework?
2. What are the advantages and disadvantages of Spring?
3. What are the application scenarios
of Spring 4. What modules does Spring consist of?
5. Which design patterns are used in the Spring framework?
6. Explain in detail the core container (spring context application context) module
7. What are the different types of events in the Spring framework
8. What are the different components of a Spring application?
9. What are the ways to use Spring?
10. Spring inversion of control (IOC) (13)
11. What is a Spring I0C container?
12 What is the role of inversion of control (loC)?
13. What are the advantages of I0C?
14. Spring loC implementation mechanism
15. What functions does Spring's IoC support?
16. What is the difference between BeanFactory and ApplicationContext?
17. How does Spring design the container ? Detailed explanation of the relationship between BeanFactory and AplicationContext
18.
What is the usual implementation of ApplicationContext? 19. What is Spring's dependency injection?
20. Basic principles
of dependency injection 21. What are the advantages of dependency injection
22. What are the different types of dependency annotations, such as implementation Way?
23. The difference between constructor dependency injection and Setter method injection
24. Spring Beans (19)
25. What are Spring beans?
26. What does a Spring Bean definition include?
27. How to provide configuration metadata to the Spring container? Spring has several configuration methods.
Message middleware MQ and RabbitMQ interview questions (2020 latest version)
1. Why use MQ? Advantages of MQ
2. What are the advantages and disadvantages of message queues? What are the advantages and disadvantages of RabbitMQ?
3. What message middleware does your company use in the production environment?
4. What are the advantages and disadvantages of Kafka, ActiveMQ, RabbitMQ, RocketMQ?
5. What are the common problems with MQ? Solve these problems?
6. What is RabbitMQ?
7. Rabbitmq usage scenarios
8. RabbitMQ basic concepts
9. RabbitMQ working mode
10. How to ensure the order of RabbitMQ messages?
11. How to distribute messages?
12. How to route messages?
13 What is the transmission of the message?
14. How to ensure that the message is not re-consumed? Or, how to ensure the idempotence of the message when it is consumed?
15. How to ensure that the message is correctly sent to RabbitMQ? How to ensure that the message recipient consumes the message?
16 , How to ensure the reliable transmission of RabbitMQ messages?
17. Why shouldn't all messages use a persistence mechanism?
18. How to ensure high availability? RabbitMQ cluster
19. How to solve the problem of message queue delay and expiration? What should I do when the queue is full? There are millions of messages in the backlog for several hours, talk about how to solve it?
20. Design MQ Ideas
Java Virtual Machine (JVM) Interview Questions (the latest version of 2020)
1. Java memory area
2. Tell me about the main components of the JVM and its role?
3. Tell me about the JVM runtime data area
4. Deep copy and Shallow copy
5. Tell me about the difference between stacks?
6. What are queues and stacks? What is the difference?
7. HotSpot virtual machine object exploration
8. Object creation
9. Allocating memory for objects
10. Dealing with concurrency security issues
11. Objects Access location
12, handle access
13, direct pointer
14, memory overflow exception
15, will there be a memory leak in Java? Please briefly describe
16, garbage collector
17, briefly describe the Java garbage collection mechanism
18, what is GC? Why GC
19 The advantages and principles of garbage collection. And consider the two types of recycling mechanisms
20. What is the basic principle of the garbage collector? The garbage collector can reclaim the memory? Is there any way to actively notify the virtual machine for garbage collection?
21. What reference types are there in Java?
22 、How to judge whether an object can be recycled?
23. In Java, when can an object be garbage collected
24. Will the permanent code in the JVM be garbage collected
25. Tell me about the garbage collection algorithms of the JVM?
Spring Interview Questions (latest version 2020)
1. Java memory area
2. What are the main components of the JVM and its role?
3. What is the JVM runtime data area?
4. Deep copy and shallow copy
5. What is the difference between stack?
6. What are queues and stacks? What is the difference?
7. HotSpot virtual machine object exploration
8. Object creation
9. Allocating memory for objects
10. Handling concurrency security issues
11. Object access positioning
12. Handle access.
13. Direct Pointer
14, memory overflow exception
15, Java memory leak? Please briefly describe
16, garbage collector
17, briefly describe the Java garbage collection mechanism
18, what is GC? Why GC
19, the advantages and principles of garbage collection. And consider two types of recycling mechanisms
20. What is the basic principle of the garbage collector? Can the garbage collector reclaim memory immediately? Is there any way to proactively notify the virtual machine for garbage collection?
21. What are the types of references in Java?
22 、How to judge whether the object can be recycled?
23. In Java, when can the object be garbage collected
24. Will the permanent code in the JVM be garbage collected
25. Tell me about the garbage collection algorithms of the JVM?
26. Mark-clear Algorithm
27, copy algorithm
Interview Questions Collection
Including basic knowledge of Java, collection container, concurrent programming, JVM, commonly used open source framework Spring, MyBatis, database, middleware, etc.
1. 283 pages of Java core knowledge written by Ali P8 Daniel
2. Interview Collection
The interview review book and the review before the interview will help you extraordinary!
3. More structure topics and video materials are displayed as follows:
Due to space limitations, the detailed information of the "Java Interview Summary" (PDF) is too comprehensive, and there are too many details. So only the chapters of some modules have been edited. Under a brief introduction, there are more detailed nodes in each chapter. content!
If you need this full version of the interview notes, three-link support, you can get the information for free-after three-link (commitment: 100% free)
quick start channel: click here! ! Code open source!
It is not easy to organize, friends who feel helpful can help, like, share and support~
Your support, my motivation; I wish you all a bright future and constant offers! ! !