Like, Java interview guide recommended by Ali P8: 41 topic PDFs (the most complete in history + essential for interviews)

"Nien Java Interview Guide"

After continuous sorting and iteration of a large number of Java interview questions, 40-year-old architect Nien compiled the 5,000-page "Nien Java Interview Guide", which is dedicated to systematic, systematic and visual sorting to form a large knowledge system. , thereby helping everyone enter a big factory and get a high salary!

For the PDFs of "Nien Architecture Notes", "Nien High Concurrency Trilogy" and "Nien Java Interview Guide", please go to the official account [Technical Freedom Circle] to obtain

Core upgrade version

Core upgrade version (V2.8): completely remember the red-black tree

During the interview process, HashMap is often the focus of the interview, and questions will be asked in a series of ways .

Therefore, red-black trees are basically necessary points for interviews . If you cannot answer them correctly, the interview will be largely unsuccessful .

Let’s take a look at the wide range of applications of red-black trees

• Starting from JDK 1.8, HashMap also introduced red-black trees: when the length of the conflicting linked list exceeds 8, it will automatically convert to a red-black tree.
• In Java, TreeMap and TreeSet both use red-black trees as the underlying data structure.
• In the underlying CFS process scheduling algorithm of Linux, vruntime uses red-black trees for storage.
• The core structure of Epoll, a multiplexing technology, is red-black tree + doubly linked list.

Red-black trees are more complex and have many scenes, which are difficult for everyone to remember.

In this in-depth course, Nien helped everyone to sort out the information thoroughly and vividly, helping everyone to easily remember the red-black tree .

Core upgraded version (V2.7): Understand netty with one picture

Netty is very difficult . Until now, there has been no picture that can give a more in-depth introduction to netty.

So, Nien drew a : Netty architecture diagram

Through this diagram, you should have a clear understanding of Netty’s core components.

This picture shows: how to query io events, how to distribute them, how to read data, how to spread data, how to write data

Links to this picture: You can refer to the history of the Crazy Maker Circle WeChat group

Core version upgrade (V2.1): Illustration of spring third-level cache

Spring third-level caching is a difficult point and is very difficult to remember. However, it is also the focus and key point of the interview .
This problem has been encountered by many friends in the community very frequently . Interviewers like to ask about spring level three cache.

However, several friends have reported to me that they know a little about the spring third-level cache issue, but they can’t remember it and can’t answer it systematically.

Many friends failed in the interview because of this problem . Therefore, Nien carried out a systematic review of the spring third-level cache .

It is the first to use finished products, semi-finished products, and raw material factories to sort out and interpret this simple and easy-to-understand model, making this super complex concept easier to understand, as shown below:

Upgrade Instructions

2023-09-19 Upgrade (V109): Upgrade instructions

Update topic 23: Mysql interview questions

• Didi Side: Talk about MySQL master-slave data synchronization mechanism

2023-09-17: Upgrade instructions

Update topic 04: Architecture design interview questions

• With 1.2 million connections per unit, how is the Xiaoai gateway structured?

2023-09-14: Upgrade instructions

Update topic 04: Architecture design interview questions

• Billion-level long connections, architectural design of Taobao access layer gateway

2023-09-12 Upgrade (V108): Upgrade instructions
Update topic 24: Spring Cloud interview questions

• Weibo side: How to achieve zero call loss in RPC?

2023-09-09 Upgrade (V107): Upgrade instructions
Update topic 01: JVM interview questions

• Weibo: JVM warm-up, what is your plan?

2023-09-07: Upgrade instructions
Update topic 04: Architecture design interview questions

• 1 million level connections, how is iQiyi WebSocket gateway structured?

2023-09-06 (V106): Upgrade instructions
Update topic 23: Mysql interview questions

• Didi side, lost 40K: because MVCC did not explain clearly

2023-09-05: Upgrade instructions
Update topic 04: Architecture design interview questions

• 20 billion calls per day, architectural design of Himalayan gateway

2023-09-04: Upgrade instructions
Update topic 04: Architecture design interview questions

• With tens of millions of connections, how does Zhihu build a long-connection gateway?

2023-09-03: Upgrade instructions
Update topic 04: Architecture design interview questions

• 20 billion daily traffic, architectural design of Ctrip gateway

2023-09-02 Upgrade (V105): Upgrade instructions
Update topic 04: Architecture design interview questions

• Multi-level cache architecture design

2023-09-01 Upgrade (V104): Upgrade instructions
Update topic 04: Architecture design interview questions

• Tens of billions of visits, how to design a cache architecture

2023-08-29 Upgrade (V103): Upgrade instructions
Update topic 04: Architecture design interview questions

• Message push architecture design

2023-08-27 Upgrade (V102): Upgrade instructions
Update topic 04: Architecture design interview questions

• Alibaba 2: How many nodes do you deploy? How to deploy 1000W concurrency?

2023-08-26 Upgrade (V101): Upgrade instructions
Update topic 04: Architecture design interview questions

• Meituan 2 side: 5 nines, high availability 99.999%, how to achieve it?

2023-08-24 Upgrade (V100): Upgrade instructions
Update topic 26: Message queue interview questions

• NetEase: Single node 2000Wtps, how does Kafka do it?

2023-08-23 Upgrade (V99): Upgrade instructions
Update topic 17: Distributed transaction interview questions

• Byte side: What is the relationship between transaction compensation and transaction retry?

2023-08-21 Upgrade (V98): Upgrade instructions
Update topic 23: Mysql interview questions

• NetEase: 25Wqps high throughput writing Mysql, 100W data is written in 4 seconds, how to achieve it?

2023-08-16 Upgrade (V97): Upgrade instructions
Update topic 04: Architecture design interview questions

• How to structure billion-level short videos?

2023-08-14 Upgrade (V96): Upgrade instructions
Update topic 04: Architecture design interview questions

• Byte2face: How to design the 10Wqps membership system?

2023-08-06 Upgrade (V95): ​​Upgrade Instructions
Update Topic 41: Real Interview Questions from Large Companies

• Exploded, relying on "bragging" to get through JD.com, with a monthly salary of 40k

2023-08-04 Upgrade (V94): Upgrade instructions
Update topic 04: Architecture design interview questions

• Big manufacturers must ask: What is the QPS of your system and how is it deployed? Assuming tens of millions of requests every day, how to deploy it?

2023-07-29 Upgrade (V93): Upgrade Instructions
Update Topic 41: Real Interview Questions from Large Companies

• It’s so cool. You can get through SF Express by “bragging”, and your monthly salary is 30k.

2023-07-28 Upgrade (V92): Upgrade instructions
Update topic 04: Architecture design interview questions

• 1000Wqps production-level IM, how to structure it?

2023-07-27 Upgrade (V91): Upgrade instructions
Update topic 26: Message queue interview questions

• Losing 30K from NetEase Part 2: Look at your awesomeness, please write a blocking queue

2023-07-26 Upgrade (V90): Upgrade instructions
Update topic 04: Architecture design interview questions

• Tencent is too ruthless: How to achieve 1 billion QPS IM?

2023-07-24 Upgrade (V89): Upgrade instructions
Update topic 26: Message queue interview questions

• NetEase lost 30K: Why use blocking queue, but not list?

2023-07-23 Upgrade (V88): Upgrade instructions
Update topic 25: Netty interview questions

• Meituan Ermian: epoll performance is so high, why?

2023-07-22 Upgrade (V87): Upgrade instructions
Update topic 04: Architecture design interview questions

• Didi Taihen: Distributed ID, how to achieve 1000Wqps?

2023-07-18 Upgrade (V86): Upgrade instructions
Update topic 04: Architecture design interview questions

• With 1 billion users, how to implement a circuit breaker and downgrade architecture? Comparison of the architecture of WeChat and hystrix

2023-07-14 Upgrade (V85): Upgrade instructions
Update topic 12: Design mode

• Shopee Side: Handwriting a Strategy Mode (Strategy Mode)

2023-07-12 Upgrade (V84): Upgrade Instructions
Update Topic 41: Real Interview Questions from Large Companies

• I was confused when I asked...Meituan asked 44 questions for his life, but after passing it, it was 600,000+

2023-07-8 Upgrade (V83): Upgrade Instructions
Update Topic 41: Real Interview Questions from Large Companies

• It exploded...Jingdong asked for 40 questions on one side, and if it passed, it would be 500,000+

2023-07-05 Upgrade (V82): Upgrade instructions
Update topic 23: Mysql interview questions

• Meituan is too ruthless: 10 billion-level sub-databases and tables, migration without downtime, how to deal with it?

2023-06-18 Upgrade (V81): Upgrade instructions
Update topic 23: Mysql interview questions

2023-06-03 Upgrade (V72): Upgrade instructions
added
Topic 41: Real interview questions from large companies

2023-03-05 Upgrade (V58): Upgrade instructions
Update topic 23: Mysql interview questions

2023-02-22 Upgrade (V51): Upgrade instructions
Update topic 04: Architecture design interview questions

2023-02-18 Upgrade (V49): Upgrade instructions
Update topic 04: Architecture design interview questions

2023-02-18 Upgrade (V48): Upgrade instructions
Update topic 34: Elasticsearch interview questions

2023-02-09 Upgrade (V43): Upgrade instructions
Update topic 22: Linux interview questions

2023-02-06 Upgrade (V40): Upgrade instructions
Update topic 23: Mysql interview questions

2023-02-05 Upgrade (V39): Upgrade instructions
Update topic 23: Mysql interview questions

2023-02-04 Upgrade (V38): Upgrade instructions
Update topic 04: Architecture design interview questions

2023-02-02 Upgrade (V36): Upgrade instructions
Update topic 04: Architecture design interview questions

2023-01-31 Upgrade (V35): Upgrade instructions
Update topic 04: Architecture design interview questions

2023-01-29 Upgrade (V34): Upgrade instructions
Update topic 23: Mysql interview questions

2023-01-20 Upgrade (V30): Upgrade instructions
Update topic 29: Multi-threaded interview questions

• 5. Penetrating volatile visibility

2023-01-17 Upgrade (V29): Upgrade instructions
Update topic 23: Mysql interview questions

• Let’s talk: What is the difference between MySQL’s ordinary index and unique index?

2023-01-16 Upgrade (V28): Upgrade instructions
added
Topic 40: Operating system interview questions

2023-01-14 Upgrade (V27): Upgrade instructions
added
Topic 39: Nginx interview questions

2023-01-13 Upgrade (V26): Upgrade instructions
added
Topic 37: Docker interview questions
Topic 38: K8S interview questions

2023-01-12 Upgrade (V25): Upgrade instructions
Update topic 03: Java basic interview questions
Topic 24: Spring Cloud interview questions

2023-01-11 Upgrade (V24): Upgrade instructions
Update topic 04: Architecture design interview questions

• 10 Big Ideas of 10WQPS Ultra-High Concurrency Architecture

2023-01-10 Upgrade (V23): Upgrade instructions
added
Topic 37: Docker interview questions

2023-01-05 Upgrade (V22): Upgrade Instructions
Topic 14: Redis Interview Questions

• Let’s talk: What is Redis’s split-brain problem? How to solve it?

2022-12-23 Upgrade (V21): Upgrade instructions
Topic 36: Dubbo interview questions

• 1. Why do you need Dubbo?
• 2. What are the main application scenarios of Dubbo?
• 3. What are the core functions of Dubbo?
• 4. What is the process of Dubbo service registration and discovery?
• 5. Dubbo’s service calling process?
• 6. What protocols does Dubbo support? What are the application scenarios, advantages and disadvantages of each protocol?
• 7. What registration centers does Dubbo have?
• 8. How does Dubbo implement service governance?
• 9. Dubbo’s registration center cluster is down. How can I consume it normally?
• 10. What load balancing strategies does Dubbo cluster provide?
• 11. What serialization methods does Dubbo support?
• 12. Tell me about the Dubbo service request process?
• 13. Can you talk about the overall calling process of Dubbo?
• 13. Talk about Dubbo’s layering?
• 13. Let’s talk about the working principle of Dubbo
• 14. If the registration center is down, can the consumer still call the provider?
• 15. How to realize the dynamic sensing service offline?
• 16. The service provider is not listed but cannot be seen in the registration center?
• 17. Let’s talk about Dubbo’s priority configuration
• 18. What is the meaning of load balancing?
• 19. What are the common load balancing algorithms?
• 20. What current limiting algorithms do you know?
• 21. What is the counter (fixed window) algorithm?
• 22. What is the sliding window algorithm?
• 23. What is the leaky bucket algorithm?
• 24. What is the token bucket algorithm?
• 25. What protocols does Dubbo support? What are the application scenarios of each protocol and its advantages and disadvantages?
• 26. Tell me about the design patterns used in Dubbo components that you know?
• 27. Through the flow chart, explain Dubbo’s service exposure process?
• 29. What are Dubbo’s registration centers?
• 30. Let’s talk about Dubbo SPI mechanism?
• 31. What is the difference between Dubbo’s SPI and JAVA’s SPI?
• 32. What are the load balancing strategies?
• 33. What are the cluster fault tolerance methods?
• 34. Let’s talk about Dubbo’s service reference process.
• 35. What is the principle behind the failure kick-out of service providers?
• 36. Why communicate through proxy objects? ?
• 37. How to design an RPC framework?
• 39. Talk about the difference between Dubbo and Spring Cloud?
• 40. Briefly describe what Nginx is, what are its advantages and functions?
• 41. How does Nginx handle an HTTP request?

2022-12-17 Upgrade (V16): Upgrade instructions
Topic 23: Mysql interview questions

• Let’s talk: What is a database transaction? Let’s talk about the characteristics of transactions?
• Let’s talk: How is MySQL’s transaction ACID implemented?
• Let’s talk: What are dirty reads, phantom reads, and non-repeatable reads?
• Let’s talk: How to achieve Transaction isolation? What is the default isolation level for Mysql transactions and Oracle transactions?
• Let’s talk: How does Mysql control the isolation level of transactions?
• Let’s talk: How to ensure that the REPEATABLE READ level does not produce phantom reads?
• Let’s talk: What is the MVCC multi-version concurrency control protocol?
• Let’s talk: What is the transaction isolation level of MVCC?
• Let’s talk: What is the relationship between the Undo Log mechanism and MVCC in Mysql?
• Let’s talk: How is MVCC implemented in Mysql?
• Let’s talk: What are table-level locks, row-level locks, and page-level locks?
• Let’s talk: What are shared locks and exclusive locks?
• Let’s talk: What are Record Locks?
• Let’s talk: What are Gap Locks?
• Let’s talk: What are Next-Key Locks?
• Let’s talk: What is intention lock?
• Let’s talk: What is an insertion intention lock?

Topic 28: JVM memory overflow practice

• Chat: How to conduct practical analysis of memory overflow OOM
• Chat: How to conduct practical analysis of memory leaks

Topic 31: Hash serial gun interview questions

• Let’s talk: Time complexity of HashMap

2022-12-12 Upgrade (V14): Upgrade instructions

• Dachang interview question: Are objects in Java necessarily allocated on the heap?
• Dachang interview question: Let’s talk, what is just-in-time compilation?
• Interview questions from big manufacturers: Let’s talk, why is HotSpot JVM called HotSpot JVM?
• Dachang interview questions: Let’s talk: strong quotation, soft quotation, weak quotation, virtual quotation? Let’s talk about the key points, their respective usage scenarios?
• How to use singleton mode in the source code of Caffeine, the king of cache?
• How to use the singleton mode in the source code of Link King skywalking?

2022-11-29 Upgrade (V12): Upgrade instructions

• Let’s talk: What is your understanding of microservices? What is the difference between microservice architecture and monolithic architecture? How does a monolithic architecture evolve into a microservices architecture?
• Let’s talk: AKF splitting principles and expansion principles for distributed applications
• Let’s talk: How Feign works
• Let’s talk: How Ribbon works
• Let’s talk: How Hystrix works
• Let’s talk: How gateway works
• Let’s talk: The differences and commonalities between Nginx and Zuul
• Real questions from central enterprises: Feign Ribbon Hystrix and the relationship between the three (key questions)

2022-11-15 Upgrade (V11): Upgrade Instructions
Nien Java Interview Guide has been updated to the V11 version, and the following interview questions have been added:

• 63: Can you tell us a few common cases that affect the performance of MYSQL?
• 64. How to troubleshoot and optimize MySQL OOM (memory overflow)?
• 65. How to optimize the batch import of 10 million data to MySQL?
• 66. What are the isolation levels of transactions in the database? What are the characteristics of each?
• 67. How does mysql implement data insertion without data and data update?
• 68: What are the ideas and techniques for sub-database and sub-table?
• 69: How to randomly query a record from MySQL with the most efficiency?

2022-11-8 Upgrade (V10): Upgrade Instructions
JVM Interview Topic

• Basic question: What is the size of String object in Java?
• Scenario question: Talk about the loading, linking and initialization of JVM-related classes?

Architecture interview topics

• Scenario question: How to design a high concurrency system?

MQ message queue interview topic

• Scenario question: Talk about the high availability, non-repeated consumption, reliable transmission, sequential consumption, and message accumulation of the message queue?

2022-7-16 Upgrade (V3.3): Added Mybatis interview questions
Chat: What is MyBatis?
Chat: Advantages and Disadvantages of Mybatis
Chat: Why is Mybatis said to be a semi-automatic ORM mapping tool? What is the difference between it and fully automatic?
...
Let’s talk: In the Mybatis mapping file, if the A tag references the content of the B tag through include, can the B tag be defined after the A tag, or must it be defined in front of the A tag?
Let’s talk: What is the mapping relationship between Mybatis’ Xml mapping file and Mybatis’ internal data structure?
……
2022-6-22 Upgrade (V3.2): Added redis-related test questions answers :

2022-6-19 Upgrade (V3.1): Add answers to questions on how to optimize redis :

New questions and answers: How to optimize redis? (Source: Real interview questions from friends)

2022-6-16 upgrade (V3.0): Add elasticsearch topic

A new topic has been added, Topic 34, elasticsearch topic , which includes dozens of common es interview questions such as " deep paging ".

For a detailed introduction to the above finished products, semi-finished products, and raw material factories, please see: Topic 5 in the pdf.

2022-5-20 upgrade (V2.6): JVM added 4 serial cannons in the method area

• Q: Could you please introduce the difference between method area and permanent generation?
• Question: What is the difference between the method area and the heap?
• Question: How to set the size of method area memory?
• Question: How to solve the OOM in the method area?

2022-5-18 Upgrade (V2.5): Added a topic on preparation for interviews with large companies.
A new topic has been added, Topic 32, the basic process and interview preparation for interviews with large companies ,

This is very important to help everyone better prepare for the big manufacturers.

2022-5-17 Upgrade (V2.3): Added Hash serial gun topic

A new topic has been added, Topic 31, Hash Serial Cannon Interview Questions ,

Hash serial gun interview questions , introducing the internal structure of hashmap, cocurrenthashmap1.7, cocurrenthashmap1.8, avl tree, red-black tree

This is very important, the focus of the interview, the absolute focus

2022-5-16 Upgrade (V2.2): Added 3 interview serial cannons

JVM memory chain gun:

What does JVM memory include? What is heap memory? What is non-heap memory? What is direct memory? What is the difference between method area and permanent generation?

Object structure serial cannon:

Given a specific class, please analyze the memory footprint of the object? How to calculate the memory footprint of an object? What parts are included in the object header?

JVM tuning serial gun:

What are the commonly used JVM startup parameters? What are the tuning commands? What factors should be considered when setting heap memory XMX?

Assuming that the physical memory is 8G, how much heap memory is suitable to set? How to enable GC log?

41 interview topics PDF

Topic 01: JVM interview questions (exclusively provided by the king of papers + the most complete in history + essential for interviews)

Topic 02: Java Algorithm Interview Questions (Exclusively for the King of Questions + The Most Complete in History + Essential for Interviews)

Topic 03: Java basic interview questions (exclusively provided by the king of papers + the most complete in history + a must-have for interviews)

Topic 04: Architectural Design Interview Questions (Exclusively for the King of Questions + The Most Complete in History + Essential for Interviews)

Topic 05: Spring interview questions__Topic 06: SpringMVC__Topic 07: Tomcat interview questions (the most complete in history + essential for interviews)

Topic 08: SpringBoot interview questions (exclusively provided by the king of papers + the most complete in history + essential for interviews)

Topic 09: Network Protocol Interview Questions (Exclusively for the King of Questions + The Most Complete in History + Essential for Interviews)

Topic 10: TCP-IP protocol (exclusively provided by the king of papers + the most complete in history + a must-have for interviews)

Topic 11: JUC Concurrency Package and Container Class (Exclusively for the King of Volume + The Most Complete in History + Essential for Interviews)

Topic 12: Design Pattern Interview Questions (Exclusively for the King of Questions + The Most Complete in History + Essential for Interviews)

Topic 13: Deadlock Interview Questions (Exclusively for the King of Examinations + The Most Complete in History + Essential for Interviews)

Topic 14: Redis interview questions (exclusively provided by the king of papers + the most complete in history + essential for interviews)

Topic 15: Distributed lock interview questions (exclusively provided by the king of papers + the most complete in history + a must-have for interviews)

Topic 16: Zookeeper interview questions (exclusively provided by the king of papers + the most complete in history + essential for interviews)

Topic 17: Distributed Transaction Interview Questions (Exclusively for the King of Questions + The Most Complete in History + Essential for Interviews)

Topic 18: Consistency Protocol (Exclusively for the King of Papers + The Most Complete in History + Essential for Interviews)

Topic 19: Zab Protocol (Exclusively for the King of Papers + The Most Complete in History + Essential for Interviews)

Topic 20: Paxos Protocol (Exclusively for the King of Papers + The Most Complete in History + Essential for Interviews)

Topic 21: Raft Protocol (Exclusively for the King of Papers + The Most Complete in History + Essential for Interviews)

Topic 22: Linux interview questions (exclusively provided by the king of papers + the most complete in history + essential for interviews)

Topic 23: Mysql interview questions (exclusively provided by the king of papers + the most complete in history + essential for interviews)

Topic 24: Spring Cloud interview questions (exclusively provided by the king of papers + the most complete in history + essential for interviews)

Topic 25: Netty interview questions (exclusively provided by the king of papers + the most complete in history + essential for interviews)

Topic 26: Message Queue Interview Questions: RabbitMQ, Kafka, RocketMQ (Exclusively for the King of Questions + The Most Complete in History + Essential for Interviews)

Topic 27: Memory leak and memory overflow (exclusively provided by King of Volume + the most comprehensive in history + a must-have for interviews)

Topic 28: Practical combat of JVM memory overflow (exclusively provided by the king of papers + the most comprehensive in history + a must-have for interviews)

Topic 29: Multi-threaded Interview Questions (Exclusively for the King of Questions + The Most Complete in History + Essential for Interviews)

Topic 30: HR interview question: After passing five levels and defeating six generals, be careful of capsizing in the ditch! (The most complete pitfall avoidance guide in history)

Topic 31: Hash Serial Cannon Interview Questions (Exclusively for the King of Questions + The Most Complete in History + Essential for Interviews)

Topic 32: Basic interview process and interview preparation for large companies (exclusively provided by the king of papers + the most complete in history + essential for interviews)

Topic 33: BST, AVL, RBT red-black tree, three core data structures (exclusively provided by the King of Volume + the most complete in history + a must-have for interviews)

Topic 34: Elasticsearch interview questions (exclusively provided by the king of papers + the most complete in history + essential for interviews)

Topic 35: Mybatis interview questions (exclusively provided by the king of papers + the most complete in history + essential for interviews)

Topic 36: Dubbo Interview Questions (Exclusively for the King of Questions + The Most Complete in History + Essential for Interviews)

Topic 37: Docker interview questions (exclusively provided by the king of papers + the most complete in history + a must-have for interviews)

Topic 38: K8S interview questions (exclusively provided by the king of papers + the most complete in history + essential for interviews)

Topic 39: Nginx interview questions (exclusively provided by the king of papers + the most complete in history + essential for interviews)

Topic 40: Operating system interview questions (exclusively provided by the king of papers + the most complete in history + a must-have for interviews)

Topic 41: Real interview questions from big companies (exclusively provided by the king of papers + the most complete in history + essential for interviews)

Say it at the end

The interview questions in "Nion Java Interview Guide" are very common interview questions. If everyone can answer questions fluently and know everything about them, the interviewer will basically be shocked and attracted by you.

Before the interview, it is recommended that you systematically review the 5,000-page "Nien Java Interview Guide PDF". If you have any questions during the question review process, you can come to talk to Nien, a 40-year-old architect.

In the end, the interviewer loved it so much that he "can't help himself and his mouth watered" . The offer is coming.

"Nien Architecture Notes", "Nien High Concurrency Trilogy", "Nien Java Interview Guide" PDF, please go to the official account [Technical Freedom Circle] at the end of the article to obtain ↓↓↓