Ali was killed by two programming problems at the beginning, pushed inward again, and finally landed (he has taken an electronic offer)

 

Preface

Before, Alibaba officially approved the written examination 4 I only got rid of this programming problem 2 Problem , Then I was brushed, and the question brushed is not enough , It still feels too delicious , Originally, I didn't hold much hope for Ali , After all, the competition is too big .

Later I saw a friend who could push inside , With the mentality of having a try , However, a few days passed without reaction ,20 The day after that, I was suddenly told to have an interview

5.14 one side ,5.15 Two or three sides , after 5.18 I received a phone call in the evening , Get the electronics offer. Coordinate Hangzhou , Position Java The backend development

one side

1. The difference between synchronous and asynchronous ？
2. Java Let's talk about thread pool , The function of each parameter , How to proceed ?
3. Java in wait and sleep What's the difference? ？ How to ensure data security under multithreading conditions ？
4. Java in volatile and synchronized What's the difference? ?
5. I understand Java Atomic class of ？ What is the principle of implementation ?
6. spring What are the main uses ？IOC What is the principle of implementation ？AOP What is the principle of implementation ？
7. mybatis Do you understand ？ It is associated with hibernate What's the difference? ？ In the project , Which one would you choose ？
8. What caching frameworks have been used ？memcache and redis What's the difference? ？ In the project , How to choose ？
9. Talk about the methods of database performance optimization ？
10. JVM How the memory model ？ What are the garbage collection mechanisms ？ How to JVM tuning ？

Two sides

1. Hashmap Underlying principle ,HashMap Is how to solve hash The question of conflict ？
2. Parameters of thread pool ,ThreadLocal? How to optimize the ？ know FastThreadLocal Do you ？
3. volatile How keywords prevent instruction rearrangement ,synchronized Can I prevent instruction rearrangement ？
4. Let's go further synchronized Lock elimination and lock optimization , What are spin lock, lightweight lock and heavyweight lock ？
5. Zookeeper To be a registry of services , If the service scale is larger than 1000, There will be a herding network storm , How to optimize the ？
6. Do you know how to implement distributed transactions ？
7. Distributed transaction two-phase commit, if the second phase timeout how to do ？
8. tcc Can you explain the principle of ？ New Seata Have you done any research ？
9. Respectively from the NIO Level and netty Let's talk about zero copy
10. Microservices , How to dismantle it , Why do you want to do that ？

On three sides

1. Introduce your project and the difficulties ？
2. RPC What is it? ？ What have you used RPC frame ？
3. Realize it by yourself RPC What to do ？
4. Yes socket be familiar with ？TCP There are several handshakes in communication ？ What have you used socket frame ？
5. Know what middleware ,dubbo,rocketmq,mycat etc. ？
6. say rocketmq How to ensure the high performance of message writing , How to ensure that messages are not lost ？
7. You used it. SpringCloud, Let's talk about it from the perspective of source code Eureka The underlying architecture and design principles of ？
8. Tell me about Spring Design idea

HR Noodles

1. What is the most difficult problem you encounter , How?
2. How to evaluate yourself
3. What do you think are your shortcomings
4. Your advantages
5. How do you usually learn
6. How long can I get in

summary

3 Interview , Each game lasted more than an hour , The third side is followed by HR Noodles

Ali's interview was really professional , And the interviewer finally gave me some advice , When studying technology, we must combine the technical background .

Interviewers have one characteristic , Will hold on to a point worth going deep or a point you haven't made clear until you make it clear , Otherwise, the interviewer will think you don't really understand .

Last

Share my preparations before this interview （ Brush questions, review materials, and some big guys' learning notes and learning routes ）, Have been sorted into electronic documents

Interview question brushing part （ The interview summary of each boss and the real problem analysis they recorded ：Spring+ Logical algorithm +MySQL+ Distributed +Redis+ Concurrent programming +JVM+RabbitMQ Wait for the interview answer 、 Study documents and notes 、 Mind mapping （xmind）） Official account ：JavaAC, Free access

Learning books （ Actual combat documents of major technical points , The book basically combines practical cases in simple terms , Easier to understand and absorb ）

Advanced technology video explanation （ More in-depth technology, reading alone is sometimes difficult to understand , believe me , With video learning, you will find Xintiandi ！）