The most comprehensive architect topic will include the following technical scope:

1. Java basics and advanced :

Collection framework: List: ArrayList, LinkedList; Set: HashSet, TreeSet
Map:TreeMap/ConcurrentHashMap；Queue:ConcurrentLinkedQueue等
Generics, reflection, concurrent programming, JVM, AIO/BIO/NIO and other fields.

2. Spring framework : injection method, IOC/AOP principle, Spring transaction implementation, isolation, Spring boot, etc.

3. Network + Linux : operating system principles, network protocols, common troubleshooting methods of Linux, etc.

4. Database Mysql : indexing, query optimization, table optimization, and the difference and combination with NoSQL.

5. High concurrency : the field of concurrent programming, and the corresponding design solutions, etc.

6. Distributed series : Distributed cache Redis, distributed architecture design series and other fields, more as follows:

The most comprehensive architect interview questions (reference answer documents have been sorted out later):

1. Java basics and advanced

Why is the String class final.
The source code, implementation principle and underlying structure of HashMap.
In reflection, the difference between Class.forName and classloader
The difference and connection between session and cookie, the life cycle of session, and session management when multiple services are deployed.
What are the queues in Java and what are the differences?
Java's memory model and GC algorithm
New features of Java7 and Java8
The operation efficiency of the two structures of Java array and linked list, under which circumstances (starting from the beginning, starting from the end, starting from the middle), which operations (insert, search, delete) are efficient
Investigation and positioning of Java memory leaks: the use of jmap, jstack, etc.

Two, spring framework

Which jar packages need to be referenced in the spring framework, and the purpose of these jar packages
The principle of spring MVC
The meaning of springMVC annotations
The connection and difference between beanFactory and ApplicationContext in spring
Several ways of spring injection
How does spring implement transaction management
The principle of springlOC and AOP
The way of loop injection in spring
Implementation Principle of Spring AOP and IOC
The difference between Spring's beanFactory and factoryBean
Spring's transaction isolation level, implementation principle
Understanding of Spring, the principle of non-singleton injection? Its life cycle? The principle of loop injection, the realization principle of aop, talk about a few in aop
terms, how do they work with each other?
Spring boot features, advantages, applicable scenarios, etc.

3. Common problems of java multithreading

After Java creates a thread, directly call start (the difference between method and run ()
Commonly used thread pool modes and usage scenarios of different thread pools
newFixedThreadPool What will happen if the number of threads of this thread pool reaches the maximum value, the underlying principle.
For the synchronization problem of communication between multiple threads, the synchronized lock is the object, and there are many specific issues related to synchronized, such as the same class and different methods have synchronized locks, whether an object can be accessed at the same time. Or - the static constructor of a class plus the impact of the synchronized lock.
Understand the meaning of reentrant lock and the difference between ReentrantLock and synchronized
Synchronous data structure, such as the source code understanding and internal implementation principle of concurrentHashMap, why it is synchronous and efficient
Understanding and use of keywords for thread-safe operations such as atomicinteger and volatile
Inter-thread communication, wait and notify

4. Network communication

http is a stateless communication, what are the request methods of http, can you define a new request method by yourself.
Socket communication, as well as long connection, subpackage, and connection abnormal disconnection processing.
The use of socket communication models, AIO and NIO.
The use of the socket framework netty, and the implementation principle of NIO, why is it asynchronous and non-blocking.
Synchronous and asynchronous, blocking and non-blocking.

Five, commonly used Linux commands

Commonly used commands under linux
In a large log file, count the number of abnormal occurrences, sort them, or specify how many rows and columns to output.
Ideas for survey questions under linux: memory, CPU, number of handles, filtering, searching, simulating POST and GET requests, etc.
shelIScreenplay

6. Database MySqI

Different storage engines of MySql
Single index, joint index, primary key index
Mysq|How to divide the table, and what to do if you want to query by pagination after the table is divided (if the query is not based on the sub-table field, it is almost inefficient and has no solution)
After splitting the table, I want multiple tables with one id to be self-incrementing, and the efficiency is realized
MySq| master-slave real-time backup synchronization configuration and principle (reading the binlog of the master library from the library), read-write separation
The four characteristics of things, and their respective characteristics (atoms, isolation), etc., how the project solves these problems

Seven, design pattern (write code)

Singleton mode: full man, hungry man. and lazy loading in Hungry Man
Factory pattern, Decorator pattern, Observer pattern, etc.

8. Algorithms & Data Structures & Design Patterns

Use a random algorithm to generate - numbers, requiring all of these numbers between 1-1000W to be generated. (Investigate high efficiency and solve conflicting problems)
Merge sort of two sorted arrays
reverse order of an array
Computes the positive square root of a positive integer
To put it bluntly, it is the common search and sort algorithms
Array and linked list data structure description, their respective time complexity
binary tree traversal
quick sort
BTree-related operations
What design patterns have you encountered in your work and how have you applied them?
What are the types of hash algorithms, their advantages and disadvantages, and usage scenarios
What is consistent hash
paxos algorithm

Nine, distributed cache

Why use cache, which caches have been used, the difference between redis and memcache
Redis data structure
The persistence method of redis, and which one is used in the project, and why
The understanding of redis cluster, how to dynamically add or delete a node, and ensure that data is not lost.

Ten, thread pool, high concurrency, NIO

Analyze the implementation principle of the thread pool and the scheduling process of the thread
How to tune the thread pool
What determines the maximum number of threads in the thread pool
Several ways of dynamic proxy
Concurrency issues with HashMap
Do you understand the application of LinkedHashMap?
The principle of reflection, what are the three ways of reflection to create class instances?
Implementation principle of cloneable interface, shallow copy or deep copy
Java NIO usage
The difference and implementation principle between hashtable and hashmap, hashmap will ask about the array index, how to solve the hash collision
The difference between arraylist and linkedlist and their implementation principles
In reflection, the difference between Class.forName and ClassLoader
What is the difference between String, Stringbuffer, and StringBuilder?
Is it possible that 2 unequal objects have the same hashcode
Briefly describe the best practices of NIO, such as netty, mina
The realization principle of TreeMap

Eleven, JVM-related (interview required)

JVM memory generation
Memory Generation Improvements in Java 8
JVM garbage collection mechanism, when to trigger MinorGC and other operations
What is the complete GC process (from ygC to fgc) in jvm, focusing on how objects are promoted to the old generation, several main jvm parameters, etc.
What kinds of garbage collectors do you know, their advantages and disadvantages, let’s focus on cms, g1
Memory recovery strategies for the new generation and the old generation
Proportional distribution of Eden and Survivor, etc.
In-depth analysis of Classloader, parental delegation mechanism
JVM compilation optimization
Understanding of the Java memory model and its application in concurrency
Instruction reordering, memory fences, etc.
00M error, stackoverflow error, permgen space error
JVM common parameters

12. Distributed correlation

The underlying implementation principles and mechanisms of Dubbo
Describe the detailed process of a service from publishing to being consumed
How to do service governance in distributed systems
The concept of idempotence for interfaces
How does message middleware solve the problem of message loss
How to deal with Dubbo service request failure
Will the reconnection mechanism cause errors?
Understanding of distributed transactions
How to implement load balancing, and what algorithms can be implemented?
What is the purpose of Zookeeper and the principle of election?
Vertical split of data and horizontal split.
zookeeper principle and applicable scenarios
zookeeper watch mechanism
How to deal with redis/zk node downtime
How to achieve uniqueness in distributed clusters-serial number
How to make a distributed lock
Which MQs have been used, how to use them, and what are the advantages and disadvantages compared with other MQs? Is the MQ connection thread-safe?
How to ensure that the data of the MQ system will not be lost
List the database sub-database sub-table strategies you can think of; after sub-database sub-table, how to solve the problem of full table query.

13. Database

The file structure stored by MySQL InnoDB
How is the index tree maintained?
Possible problems with database auto-increment primary key
Several optimizations of MySQL
mysq|index why use B+ tree
Related processing of database lock table
Index failure scenario
How to safely modify the same row of data under high concurrency, what are optimistic locks and pessimistic locks, what are the two types of INNODB row-level locks, and explain their meanings
Will the database be deadlocked, give an example of deadlock, mysq | how to solve deadlock

Fourteen, Redis & cache related

How to solve the concurrent competition problem of Redis Do you understand the CAS operation of Redis transactions?
How cache machine additions and deletions have the least impact on the system, - the implementation of consistent hashing
Several methods of Redis persistence, what are their advantages and disadvantages, and how to achieve them
Cache invalidation strategy for Redis
The solution to cache penetration
redis cluster, high availability, principle
There are 20 million data in mySQL, and only 200 thousand data are stored in redis. How to ensure that the data in redis are all hot data
Use Redis and any language to implement a piece of code for malicious login protection, and limit each user ld to log in at most 5 times within 1 hour
Redis data elimination strategy

In response to the above questions, I compiled a Java interview analysis document, including collections, JVM, concurrent programming, Spring, MyBatis, microservices, Redis, Dubbo, design patterns, data structures, distributed, etc.! , due to the limited space, in order to facilitate your viewing, here are the contents of each part and screenshots of the answers in the form of pictures!