Missed the golden three silver four, found a job for 4 months, interviewed 15 companies, and finally got 3 offers, ranking P7+

I also want to say , Change jobs this year , It's really not a good opportunity , but 6～8 The month is in the cold winter , A good time .

Everyone is talking about gold, silver and four , Indeed, there were more posts at that time , But there are many resumes in the market , The competition is also fierce .

Basically 3-4 In January, we will see opportunities in the market , Most of the posts left are optimized and vacated years ago or after , Most of the students who are interested in leaving haven't mentioned leaving , Basically 4 You can get it at the end of the month offer, At least wait until 5 Only in the month will the pit be empty again and again , therefore 5-6 There will be many new ones in the month offer And the resignation is empty hc.

and 3-4 month , Because there are many resumes in the market , Dismissed 、 Really want to change jobs , Just look around …… There are all kinds of talents in the market , As a result, some companies have high requirements for resumes , Although there are some interview opportunities , Unless you're really good , The competition is particularly fierce .

Instead, it's 6-8 month , Most of the students have been baptized by a round of interview and wait-and-see , Get offer I have joined the new company , Students on the sidelines may have given up because of the hot summer , Go back to work honestly ;

Plus, it's a hot summer , Some students who don't really want to find a job may also recuperate , Those who are still looking for jobs are basically very determined to find jobs .

At this time, the enterprise is also a relatively small labor shortage period , Fewer people have submitted resumes , The position is vacant again , Enterprises HR Of KPI The pressure is great , If this time can continue to insist , It is really a relatively good opportunity to find a job .

In particular, it can withstand the scorching sun , Find all kinds of excuses to go out for an interview , This is ahead of many people , So the probability of passing the interview will be higher .

It is through this period of time that I insist , Find your present job . The students who are leaving the company recently basically follow this rhythm , So throughout the year , Although this year is a cold winter , But there is also a rare warm moon in the cold winter , Students who are determined to find a job must seize the opportunity .

The following content of the article is mainly to share the experience and personal learning suggestions , It involves a lot of PDF file （ Interview question bank 、 Learning notes 、 Practical documents 、 Brain map, etc ）, Because of the limited articles , Need these documents , Please get it at the end of the article

database

• Use mysq1 What are the principles of indexing ?

• Index what data structure ?

• B+tree and Btree What's the difference ?

• mysq What are the storage engines ? What's the difference ? Be specific !!

• How to design the database layer of high concurrent system ?

• What are the types of database locks ? How to achieve it ?

• What are the database transactions ??

Sub database and sub table

• How to design the scheme of database and table division that can expand and shrink dynamically ???

• Which database and table middleware have been used , What are the advantages and disadvantages ,

• Let's talk about the underlying implementation principle of the database and table middleware you know ?

• Now I have a system that doesn't divide databases and tables , In the future, the system needs to be divided into databases and tables , How to design ,

• Let the system without sub database and sub table dynamically switch to the system with sub database and sub table ???

• Do distributed transactions know ? How did you deal with it ?TCC? If there is a network reason , What can I do if the Internet doesn't work

• Why do you need to divide the databases and tables ???

• What are the algorithms for distributed addressing ? Know the consistency hash Do you ?

• Write it by hand java Implementation code ?? If you userId To touch the slice , Then I want to check the data in a continuous period of time ??

• How to solve the primary key problem of sub database and sub table ? What's the solution ??

Ali 5 Complete answers to all questions + analysis ：

Distributed cache

• redis and memcheched What's the difference ? Why single threaded redis More than multithreaded memched Be efficient ?

• redis What data types are there ? What scenarios are they used in ?

• reids How does master-slave replication work ?redis How to implement the cluster mode of ?redis Of key How to address ?

• Use redis How to design distributed locks ? Use zk Is that OK ? How to realize ? Which one is more efficient ??

• know redis Is it persistent ? What are the advantages and disadvantages ?? The specific underlying implementation ?

• redis What are the expiration policies ?LRU? Write -- Next java Version of the code ??

Distributed service framework

• The way dubbo Implementation process ? Can I continue to communicate if the registration center hangs up ??

• zk Do you know the principle ?zk What can I do ?Paxos Does the algorithm know ? Let's talk about the principle and implementation ??

• dubbo Which serialization protocols are supported ?hessian? Say one Fhessian Data structure of ?PB Do you know? ? Why? PB Efficiency is the highest ??

• know netty Do you ?netty What can I do NIO,BIO,AIO What are they ? What's the difference ?

• dubbo What are the replication balance strategy and high availability strategy ? Dynamic agent strategy ?

• Why split the system ? It's not necessary to split it dubbo Is that OK ?dubbo and thrift What's the difference ?

Meituan 4 Complete answers to all questions + analysis ：

​

Distributed message queuing

• Why use message queuing ? What are the advantages and disadvantages of message queuing ?

• How to ensure the high availability of message queue ? How to ensure that messages are not consumed repeatedly ?

• kafka,activemq,rabbitmq,rocketmq What are the advantages , Shortcomings ???

• If you write a message queue , How to design architecture ? say - Think about it

Distributed search engine

• es How is the working process of ? How to realize distributed

• es In the case of a large amount of data ( Billions of levels ) How to improve the efficiency of query ?

• es What kind of working process is the query of ? At the bottom lucence Introduce it ? Inverted index, you know ?

• es and mongdb What's the difference ? What scenarios are they used in ?

• High concurrency and high availability architecture design

• How to design a high concurrency and high availability system ?

• How to limit the current ? What to do in the project , Let's talk about the implementation ?

• How cache is used ? What are the consequences of improper use of cache ?

• How to fuse ? What are the fuse frames ? Do you know the specific implementation principle ?

• How to downgrade ? How to split the system , How to split database ????

headlines 4 Complete answers to all questions + analysis ：

​

JVM

• Please introduce JVM Memory model ?? What kind of garbage collector have you used ? Talk about it all ?

• Send frequently online ful1gc How to deal with it ??CPU What to do if the usage rate is too high ?

• How to locate the problem ? How to solve ? Let's talk about solutions and solutions .

• Do you know the bytecode ? What are the bytecodes ?

• IntegerX5,inty=5, Compare x=y What steps have been taken ?

• Let's talk about the class loading mechanism ? What are the class loaders , What files do these class loaders load ?

• Write a class load Demo

• know osgi Do you ? How did he achieve ???

• What have you done JVM Optimize ? How to use ? What effect is achieved ???

• class.forName("java.langString") and String.class.getClassLoader().LoadClass("java.lang.String") What's the difference ??

Spring

• spring What are the mechanisms ?AOP How does the bottom layer realize ?I0C Well ??

• cglib Do you know? ? He and jdk What's the difference between dynamic agents ? Handwritten jdk Dynamic agent ?

Communication protocol

• The way TCP/IP four layers ?

• http workflow ???http1.0http1.1http2.0 What are the specific differences ?

• TCP Three handshakes , The workflow of four-tier breakup ? Draw a flow chart ? Why not four, five or two ?

• Draw a picture. https workflow ? How to realize it ? How to prevent being caught ??

Algorithm

• Relatively simple , I have a file , Yes 45 Billion Arabic numbers , How to remove the weight ? How to find the largest number ?

data structure

• Binary tree and red black tree etc .

Open source framework knowledge

• In a nutshell tomcat structure , And its class loader process , Thread model, etc .

• tomcat How to tune , What parameters are involved .

• Tell me about Spring Loading process .

• Spring AOP Implementation principle of .

• Tell me about Spring Propagation properties of the transaction .

• Spring How to manage affairs .

• Spring How to configure transactions （ Say something specific about the key xml Elements ）.

• Tell me about your right Spring The understanding of the , The principle of non singleton Injection ？ Its life cycle ？ Principle of cyclic injection ,aop Implementation principle of , say something aop Some of the terms in , How they work with each other .

• Springmvc in DispatcherServlet Initialization process .

• netty Thread model of ,netty How to base on reactor Implemented on the model .

• Why choose netty.

• What is? TCP Sticky package , unpacking . What is the solution .

• netty Of fashwheeltimer Usage of , Realization principle , Whether the call is not on time , How to solve .

• netty How to deal with the heartbeat under the weak network .

• netty What is the communication protocol of .

• springmvc Notes used , What is the role , principle .

• springboot Activation mechanism .

After being brutally abused by bytes , How I got Ali offer？

There are also skills and methods to find a job ：

1） He has a very clear purpose in looking for a job . At the beginning of his job search, he listed several companies he particularly wanted to go to , Put them in the same category .

2） Continuously test and accumulate experience ： He also put some of them on the market hc The classification of the company , Two category 、 Three types of companies , Priority will be given to three categories 、 Class II companies submit resumes , To check your resume and accumulate interview experience , These three types of companies are similar , Resume and interview experience are also similar .

3） The third step is to leap ： cram for + Brush problem

In the third step , That is to make yourself a qualitative leap . As for the two aspects of mending and brushing questions , I also sort out some of my personal information , It's my own way of doing it , I hope it has reference value ：

reminder ： This warehouse will be updated all the time , Free of charge , Put it at the end of the article .

​ Job hopping

​ Practical part

​ Interview questions for large factories （350+ topic ）

​JVM Summary of interview questions （100+ topic ）

​Tomcat Summary of interview questions

​Tomcat Optimize relevant interview questions （60+ topic ）

​Mysql Summary of interview questions （ One ）

​Mysql Summary of interview questions （ Two ）

Spring Source depth analysis

​Redis Summary of common interview questions （300+ topic ）

​Zookeeper Summary of common interview questions （50+ topic ）

​Java High frequency core interview question bank （1000+ topic ）

Last ：

Finally, I hope you can also win the big factory offer, Mutual encouragement ！

Because there are too many files , The whole exhibition will affect the space , For the moment, let's list some screenshots , If you need a friend, just add a little assistant ​