Many Java developers may not have long working experience or rich working experience before the interview, so they do not know what kind of questions Internet companies or first-tier Internet companies will ask in the technical interview. In addition, they may not be fully prepared for the interview. After a few rounds, they will be confused by the interviewer’s questions and finally end up in a fiasco. In view of these, collected and sorted out some well-known big factory interviews, here to share for your reference, so that the readers who are about to interview or have the idea of job-hopping know what kind of questions they like to ask in the interview of big factories

Let’s get down to business

Pinduoduo (Three sides)

One side

1. Introduce yourself briefly.

2. How to configure SpringBoot?

3. Where can the application.properties and application.yml files be stored? Priority?

4. How does SpringBoot automatically configure?

5. How does SpringBoot change the port number?

6. How can I enable the SpringBoot feature?

7. Which endpoint to visit for Bean assembly report information?

Describe the processing flow of thread pool.

9. How do I activate an environment configuration?

10.SpringBoot reads configuration related annotations.

11. How does SpringBoot change the port number?

Second interview

1. Describe the workflow of Spring MVC?

2. Describe the workflow of DispatcherServlet?

3. What is MVC? What are the benefits of the MVC design pattern?

4. What is the general annotation of the controller in SpingMvc? Is there any other annotation that can replace it?

5.@Controller The role of annotations.

6.@ResponseBody The role of annotations.

7. How does Spring MVC set redirection and forwarding?

8. How does Spring MVC call AJAX?

On three sides

1. Detail the JVM memory model.

2. Why should JVM memory be divided into new generation, old generation, persistent generation? Why should the new generation be divided into Eden and Survivor?

3. Why Eden and Survivor? Why have two Survivor zones?

4. What is a complete GC flow in the JVM and how objects are promoted to older generations.

5. How much do you know about the JVM memory model, such as reordering, memory barriers, happening-before, main memory, working memory?

6. Finally, talk about the projects you worked on, the technical architecture and the core coding you were responsible for.

Ali (Three Sides)

MySQL+Redis+ Messaging middleware +Zookeeper+ microservices

One side

1. What are the differences between MyISAM and InnoDB?

2. What are the isolation levels of MySQL transactions?

3. What MySQL index related optimizations have been made.

4. A brief description of the database paradigm.

5. How to page query a table with 10 million pieces of data?

6. How to deal with the slow query caused by the increasing amount of order table data?

7. What are the components of MySQL and what are they used for?

8. What is the problem with MySQL query cache? When should it be used?

9. Is a unique index faster than a normal index? Why?

10. How to restore data from MySQL half a month ago

Second interview

1. What advantages does Redis have over memcached?

2. What data types does Redis support?

3. What kinds of data elimination strategies does Redis have?

4. Why does Redis need to put all data in memory?

5. What should Redis cluster solution do? What are the options?

6. Under what circumstances will the Redis cluster solution make the whole cluster unavailable?

7. What scenarios are suitable for Redis?

8. What does Redis have to do with Redisson?

9. What are the advantages and disadvantages of Jedis compared with Redisson?

On three sides

1. Introduce yourself

2. Describe the concurrent projects from design to deployment according to the process.

3. How to implement master/slave synchronization and transaction?

4. What are the similarities and differences between metaQ and kafka?

5. Do you know any middleware in Ali? How does it work? What are the features of other open source message queues?

6. What are the types of Znode?

7. What are the deployment modes of Zookeeper?

8. Is the Watch listening notification of Zookeeper to the node permanent? Why not permanent?

9. What is the working status of the Zookeeper Server?

10. Talk about your understanding of SOA and microservices, and the adjustments and challenges of distributed architecture at the application level.

11. A three-year to five-year career plan? Is there anything you want to ask me?

Today’s Headlines (Three sides)

One side (50 minutes)

  1. What are the basic components of Linux?

  2. Why is the Linux architecture divided into user space and kernel space?

  3. What are the basic differences between BASH and DOS?

  4. What system log files does Linux have?

  5. Java GC mechanism? What GC Roots do you have?

  6. Red black tree, five features, insert and delete, time complexity?

  7. Hashmap, how to expand, how to deal with data conflicts? How to efficiently implement data migration?

Second interview (40 minutes)

1. Introduce yourself and tell me what you are good at. 2. Explain the redis data structure. 3. How much do you know about design patterns? 4. What are the differences between the three agents in the design pattern? 5. When is HashMap used and when ConcurrentHashMap used? 6. Why is Java8 concurrency better?

Three sides (about 1 hour)

1.MySQL index implementation, InnoDB index, how to achieve b+ tree index, why use B + tree as index node, how much data stored in a node, how to specify the size, corresponding to the disk page.

2. If Redis has 100 million keys, will using keys affect online services?

3. How many characters does builder mode usually include?

4. Code to implement template method pattern.

5. How to implement primary/secondary synchronization of MySQL data?

6. What are the plans for the future?

7. Is there anything you want to ask me?

Jingdong (Three sides)

Spring Cloud+ seckill +Redis

One side

1. Introduce yourself briefly.

2. What optimizations have been made for hashMap and concurrentHashMap in JDK1.8?

3. Difference between synchronized and ReentranLock?

4. The ThreadLocal? Application scenarios?

MySQL > select * from ‘MySQL’ where ‘deadlock’ occurs.

Transaction ACID, where the isolation of a transaction is explained in detail.

7. ThreadLocal? Application scenarios?

8. What is the difference between ArrayList and LinkedList?

9. How does HashMap work?

10. What is a binary tree?

Second interview

1. What about Redis sentry, replication, clustering?

2. Is Redis single threaded?

3. What are the basic components of Linux?

4. What interprocess communication method does Linux use?

5. What are forward and reverse proxies?

6. What attribute modules does the Nginx configuration file nginx.conf have?

7. How to use Nginx to solve front-end cross-domain problems?

8. What technology has been optimized in the work?

On three sides

1. What modules does Spring consist of?

2. What design patterns are used in the Spring framework?

3. Take a closer look at the core Container (Spring Context) module.

4. What are the different components of a Spring application?

5. What are the technical requirements for high concurrency application scenarios? How to design architecture?

6. Finally, talk about the projects you worked on, the technical architecture and the core coding you were responsible for.

Finally:

In view of the recent many people in the interview, I have also sorted out quite a lot of interview materials, there are also other big factories. I hope I can help you.

All interview questions contain answers, the article space is limited, can only show you the part of the interview questions, if you need to get the full version, you can like this article and click here for free access to screenshots