one side

Introduce yourself, project
Thread creation method, thread pool, what parameters? Saturation strategy?
Which design patterns? What design patterns are used in Java? Do you understand the dynamic proxy model?
Design pattern used by spring?
In a web request response, which part is the most time-consuming, tcp handshake? Business logic processing? Network delay? Database query? Browser resolution?
When will the index become invalid? Talk about an index optimization problem encountered, how to troubleshoot the problem of SQL slow?
The usage of synchronized, if you lock the method, what object is locked? If it is a static method, what is the lock?
How to expand ArrayList? How to expand HashMap? What kind of tree is the red-black tree?
Why rewrite hashcode?
Under what circumstances will CurrentHashMap lock the entire structure?
In JDK1.7 and 1.8, what is the difference between HashMap and CurrentHashMap (red-black tree)?
How to convert HashMap from linked list to red-black tree? If a null key is stored, where is it placed in the bucket?
The 5 major states of the thread, please draw a picture to demonstrate the flow from creation to completion?
The difference between sleep and wait, what is the state of the thread after wait is awakened?
CMS features, what are the garbage collection algorithms? Their respective advantages and disadvantages, what are their common disadvantages?
What is forward proxy + reverse proxy?
The role of Hbase, what is the idea of MapReduce?
How does the communication between Master and Slave work?
Talk about your understanding of the design ideas of the SpringMVC architecture?

Two sides

What are the load balancing algorithms? Understand the diversion of Nginx?
How to solve high concurrency?
How does Mybatis use transactions?
The difference between mysql's myisam and innodb, and why use it like this?
Handwriting database connection pool
Asked about the details of redis, distributed cache, middleware, and the usage scenarios of the project.
Actual working JVM tuning experience, with examples
Optimistic and pessimistic locking (Java and database)
How to optimize the amount of large data and the corresponding technical solutions? What do you think of the prioritization?

Three sides

Have you ever encountered a server avalanche in your work? Do you know what circumstances usually cause avalanche scenes?
Talk about the concurrent programming that you are familiar with. What technologies will be involved and where are the corresponding technologies applied?
Talk about the storage methods of distributed sessions, comparisons and differences, which one do you think is better?
Have you been exposed to a distributed global unique ID? What kinds of generation methods are there? Their strengths and weaknesses?
What does the distributed architecture design include, and what technologies do you apply in your work?
You are leading a technically challenging project. Where are the challenges and how to design and solve them?
Tmall double 11 spike, the overall design idea?

HR face

What is your personal greatest weakness?
What is the biggest challenge encountered in work and life? How was it overcome?
What are the future plans?
What are your hobbies

The above are the three-sided questions of the Tmall Core Technology Department. The latest summary of the scope and answers of the Ali advanced Java required exams is for reference only~

How to get answers

Tmall Core Technology Department (4 topics): spring + JVM tuning + distributed + load balancing, etc.