Let me write it out front

Position: Java back-end development

Interview record: Bytedance kneels on two sides, Panyoduo kneels on one side, People.com receives offer on three sides, still in progress…

background

My magic all 211 slag master, graduate student and undergraduate course are machinery (old mechanical person), but hear machinery this line treatment is really not good, entity industry pull down, hence the idea that the heart gives rise to turn computer. During this period, I encountered a lot of setbacks. On the one hand, I was under pressure from the teacher, and on the other hand, I was really isolated and helpless at the beginning of my self-study. I didn’t have any clue about what to learn [very broken].

byte

One side

In addition to the basic personal information, it is best to introduce your technology stack, project information.

What is the JVM memory barrier? What does it do? Volatile principles?

What are the common garbage collectors and what are their characteristics? STW? Safer? JVM heap memory model?

Synchronized lock upgrade? The principle? Concept of deadlock? What is the effect on static methods?

Does CAS understand? What’s the problem? How to solve it?

Mysql Index optimization Principles? How to optimize SQL? What is the underlying index structure?

TCP three handshakes and four waves? Sticking and unpacking?

Three problems with Redis Cache? How to solve the cache breakdown? Redis implements distributed locking?

What are the intermediate technologies? What are the application scenarios and implementation principles of rabbitMq?

Linux Common commands? Count the number of characters?

KMP algorithm? Fast row? (Hand tore the quick row, but KMP stuck in half)

Issues related to the project, such as table relationships, concurrent processing, use of redis cache, logon implementation, etc

Ask a special basis, the answer is ok, should have two sides

Second interview

To introduce myself

JVM tuning parameters? Young GC and Full GC? Generational age? The CMS?

How does HashMap work? 【 Difference between 1.7 and 1.8, capacity expansion mechanism, hash conflict, when the linked list turns to red black tree, why use red black tree, etc. 】

Rentrantlock? AQS principles? Fair and unfair locks? A deadlock?

Java object memory layout? Which property is the locking object related to?

Mysql lock mechanism? What is the difference between read and write Locks? Query logs slowly? Master-slave replication? What are the features of InnoDB and how do they compare to Memory?

Redis cache and database consistency? How does Redis epoll?

Design patterns? DCL?

Dynamic programming [not]? Minimum spanning tree? ACM automata?

Two algorithms did not answer, no idea, game over

A lot of spelling

When the interviewer heard that I was a non-major, he immediately lost interest in me, ha ha ha

One side

To introduce myself

JVM heap memory model? Memory barriers?

What is the difference between blocking IO and non-blocking IO?

How does The HashMap layer work? Expansion Mechanism? Hash conflict?

The CAS theory? Existing problems and solutions? How synchronized locks are upgraded? Deflection locking principle?

Optimistic lock and pessimistic lock? Application and principle?

Mysql Index optimization Principles? What about SQL tuning?

DCL?

Linux Common commands?

Radix sort? LRU? List reversal?

The performance is average, but the interviewer thinks I am not a major, do not want, purr

The people network

One side

Introduce yourself (aah, aah)

How does HashMap work? 【 From 1.7 to 1.8 list addend group plus red black tree, hash conflict, expansion time, the list to red black tree, why red black tree is better than B+ tree 】

What are the garbage collectors? Which is the new generation and which is the old? CMS features? What is STW? Safer? Garbage collection process? JVM tuning parameters?

What is a memory barrier? Why should DCLS be volatile?

Heap memory model? What’s the ratio? How to handle memory allocation?

Mysql storage engine, features? Is it different from memory?

How does Redis implement distributed locking? Three big questions? Data consistency?

What are the middleware technologies? Nginx reverse proxy and forward proxy?

How synchronized locks are upgraded?

The lifecycle of Spring’s bean objects? What’s the role of beanProcessor?

How to implement current limiting and circuit breaker in hystrix?

Second interview

To introduce myself

The JVM class loading process? What is parental delegation?

Producer, consumer design pattern on-site writing case?

How does volatile achieve memory visibility?

Q: What are the differences between mysql read and write locks? Application Scenario Selection? Slow Query Log Analysis?

Index optimization? Mysql Slow query log?

What problem does the Bloom filter solve and how does it work? How to record the monthly activity of an app with Redis?

Spring aop and IOC implementation principle? What’s the difference between SpringBoot and Spring?

TCP sticking and unpacking? Three handshakes and four waves?

What is asynchronous? How does rabbitMq work and how to use it?

What problems does CAS solve? What’s wrong with it? How to solve it? And synchronized?

Questions in the project: table structure, which fields are indexed, how are table relationships, sequence diagram for order processing business, sequence diagram for captcha login function, etc.

Three sides (HR side)

I talked about my personal situation, whether I would like to become a regular intern, how many days a week I can come, the salary, and I met the department leader. It was a sincere and nice interview, and the most important thing was to regain my confidence.

conclusion

Immediately gold nine silver ten, in the end of the article the author sorted out a lot of information for you! Including the first line of large factory Java interview questions summary + each knowledge point learning thinking guide + a 300 page PDF document Java core knowledge point summary! Friends in need, please move to the public number: future light, self!!