Foreword:

Gold three has passed, and now it is silver four. As far as I know, many people will choose to change jobs in March. Why do everyone choose to quit and change jobs in March? Of course, the New Year just passed, and everyone may think that the old company's treatment is not very good? Salaries are not high enough, want to change to a new environment, etc. Therefore, March has become a peak season for recruitment and job-hopping, so why is April not as good as March? I believe you don’t need to tell me that everyone knows that. After all, everyone went to join in the fun in March, and they all went to recruit and interview. There are very few people left for recruiting and interviewing in April, and those who haven’t found a job in April can use the old It's not an exaggeration to say that you tiao came, and the company still recruited people in April, and those few books were recruited by some big bosses.

Then why do I say that silver is four more than gold and three fires? Because, most people think that the job in April is hard to find, and the salary will not be very high, the environment is not known, and there are still a lot of requirements, interviews are difficult, etc., but as far as I know , the employment situation in April is better than that in March, and the treatment, salary, environment, etc., are better than those in March. According to what I learned from a friend James, just a few days ago, the two students he brought with him successfully interviewed Ali, and he also helped me sort out the interview summaries of the two students. Here, I will share with you. , I hope that everyone who is looking for a job in April, this article of mine can help you.

Interview summary

Then for the two students, I will use A and B instead

A student

Round 1: Initial phone interview

The second round: technical interview [technical positions try to avoid talking about management work]

The third round: executive re-examination

Fourth round: HR final confirmation

One side: first confirm the degree of intention to Ali (if you are in a different place, you will consider the degree of intention to work in Hangzhou! Ali attaches great importance to this); secondly, the interviewer will usually do specific technical exchanges for the projects you have done. Will pay more attention to whether the individual has a good grasp of the details of the project, mainly examine the technical foundation and principles of java, such as the Spring framework, database and JVM, and also communicate about the implementation of distributed and thread pools, etc., focusing on whether There are technical and technical highlights [not necessarily every aspect is very powerful, but there must be bright spots];

The second side: the technical side. According to the project, we have an in-depth understanding of the technical strength, your knowledge, your problem-solving ability and your ability to use technology flexibly. Through this process, we also examine teamwork ability, learning initiative and innovation. Select 2-3 typical projects you have done to do a careful technical review and your own unique understanding [this will become your bonus item];

Three aspects: their final executive re-examination will involve related technical issues, most of which are macro-control of your overall values (such as self-motivation, responsibility, mentality, work passion, etc.)

HR confirmation: Basically, it is to understand your mentality, ability to withstand pressure, role in work, general planning for the future and your intention to Ali from the general direction

[Technical basics and questions just read the book and prepare it. If you don't understand it, it doesn't matter if you don't understand it directly; check the details of the project, and talk about your own technical highlights according to the project. You can express it clearly and guide you. The interviewer will ask you technical questions that you are good at, and you can play to your heart’s content]

The characteristics of talents that Ali prefers: enthusiasm for technology, strong technical basic strength; initiative, good at teamwork, good at summarizing and thinking;

Ali's interview questions will be relatively low-level

1. Java memory structure, the implementation method of spring aop, java database problem location and performance tuning;

2. About the continuation hierarchy of Java exceptions, describe the continuation relationship of exceptions;

3. What is the difference between overloading and rewriting in java, and what keywords are used respectively;

4. About distributed message queue, distributed cache;

5. About hashmap source code implementation, jdk

6. About design patterns, uml, jvm memory recovery mechanism

7. How to start a java thread? What are the ways of locking in java, how to write it?

8. Understanding of optimistic locking and pessimistic locking;

9. How to optimize SQL in ORACLE and what are the methods? What are the characteristics of transactions and what are the levels of isolation in ORACLE?

10. Introduce a typical project you have done recently;

11. What problems did you encounter in the project and how did you solve them;

12. What is the number of users currently supported by the system? If the number of users increases by 10 times, what kind of problems will occur in the system, and how to redesign the system [Here I mainly want to know your problem prediction ability and problem solving ability, and examine your ideas]

13. What is the principle of using memcached

14. How to store data in the memcached cluster and introduce this process. Follow-up questions, talk about the implementation principle of the consistent hash algorithm.

15. How the heap is managed in the JVM, and the memory recovery mechanism of the JVM, introduce

16. Distributed transaction implementation

17. Hot account questions (will be asked in the project)

The first round of technical interviews (electronic) involves Java basics (for reference):

session

java lock

gc principle

hashmap

listlink arraylist difference

aop principle

Multithreading

Kafka principle and fault tolerance

spark hadoop principle

redis synchronization mechanism

classLoader mechanism

HTTP protocol

Restrictions on cookies

HashMap key requirements, hashcode is consistent whether two objects are equal

The principle of JVM

Involves a wide range, including talking about the problems encountered in the project, in order to discuss in depth.

XX：

Introduce how your job responsibilities, technical or management are assigned

Introduce the project, the technology involved, and explain the entire process. Then he is interested and asks in depth

Then I talk about some jvm, nosql and the like

If the server response is slow, what should you do to troubleshoot the problem

How to track the time of a method with minimal interference with business processes

Audition interview-java:

Candidate introduction The current technical management focus is on;

Understanding of the corresponding positions recommended by Ali;

What is the system design like?

Do some architecture, where does the data source come from and ask in depth;

Module boundaries, caching mechanisms;

When selecting technical models, the difference between A and B;

How to use multithreading, what are the benefits, and the difference between processes;

multithreaded process;

The method of multi-thread synchronization, how to implement it in the X project;

The embodiment of distributed architecture in your current project;

What is used for cross-host communication, interfaces, etc.;

big data storage;

Conclusion: what do you think you are good at, the route you want to take in the future, technology or management;

Java interview questions sharing:

The two modes of JMS are those;

How to update the rich client;

What functions should an enterprise data bus like ESB have?

system architecture design;

How to control the session in the cluster;

How to know which modules in java memory consume more memory;

Parameter adjustment of the application server.

Student B

Basics

interview questions

1. junit usage, the execution order of before, beforeClass, after, afterClass

2. Distributed lock

3. nginx's request forwarding algorithm, how to configure forwarding based on weight

4. What is wrong with implementing redis with hashmap (deadlock, infinite loop, available ConcurrentHashmap)

5. The state of the thread

5. Thread blocking method

6. The difference between sleep and wait

7. The underlying implementation of hashmap

8. 10,000 people grab 100 red envelopes, how to achieve (without queue), how to ensure that 2 people cannot grab the same red envelope, distributed locks are available

9. java memory model, garbage collection mechanism, unreachable algorithm

10. Two Integer reference objects are passed to a swap method to exchange references inside the method. After returning, will the values of the two references be found to change?

11. The underlying implementation of aop, how dynamic is the dynamic proxy, if there are 100 objects, how to dynamically proxy these 100 objects

12. Have you used maven install. maven test. git (make install is to install the local jar package)

13. Various configurations of tomcat, how to configure docBase

14. Several ways of spring's bean configuration

15. Configuration of web.xml

16. Spring's listener.

17. The implementation mechanism of zookeeper, there is a cache, how to store the registered service

18. Will IO block? Is readLine blocking?

19. Have you used spring's thread pool or java's thread pool?

.........(I can't remember yet)

If you can answer 70%, the breadth of the basics is OK. If not, then make up for what is missing. The breadth has been reached, and it is necessary to have depth on individual hot issues. Everyone's energy is limited, and two hot issues can be appropriately selected for in-depth exploration. For example, HashMap, not only can you say what the source code is to achieve, but also understand what improvements have been made from JDK 1.7 to 1.8, why such improvements, how ConcurrentHashMap is implemented, and what optimization measures have been made for concurrent scenarios , What is the difference between the implementation of JDK1.7 and 1.8. Understanding these can take a lot of effort. However, once you ask this knowledge point that you are very proficient in during the interview, you will basically enter your home field. This can play the role of finalizing the decision, leave a strong impression on the interviewer, and even directly determine the success or failure of the interview. Therefore, prepare at least one or two very proficient knowledge points, not more, but more proficient than the interviewer and other job seekers. This bet is luck, as long as you can teach the interviewer a lesson on one question, you can make the other party have the illusion of "you are very powerful".

Take notes on all the basic knowledge, review more before the interview, and brush the questions together, the problem will not be big.

Project articles

To answer the project questions well, the core is to be well prepared in advance. First, carefully review the projects you have done. Then select the most valuable parts, write a summary document about the project, and clarify the structure and design ideas of the project. The second is to try to recall the difficulties encountered at the time, the pits that I stepped on, and how I thought and dealt with it, as well as thinking about the follow-up improvement of the project. This is very important and must be written down. After the document is written, it must be refined and supplemented repeatedly. Use this document as the guideline during the interview, so that you can talk freely and deal with it calmly.

Emotional Intelligence

During the interview, there may be some personality questions interspersed. For example, why did you leave/want to change jobs, what do you think about technology and business, what do you know about our company, what do you know about our business, what do you want to ask me, and what do you think are your advantages/disadvantages. Technical students are often lacking in emotional intelligence. If they are not prepared, accidentally saying a wrong word during the interview may lead to the failure of all previous efforts. Especially in Ali, HR has a veto power. Then, the first point to deal with such problems is to prevent them in advance. You can take a piece of paper in advance, guess the questions the other party may ask, write out the standard answers, scrutinize them repeatedly, and then memorize them. For example, for the question "What do you think you have?", my standard answer at that time was, "I think the most difficult thing for people to understand is yourself, so I want to borrow my former leader's evaluation of me, XXX is a... . of people". My standard answer is designed based on the principle of "third-party evaluations are more credible". The second point is to be humble when answering questions, and don't have negative energy. For example, "Why did you leave/want to change jobs?" For this question, don't complain about the company or colleagues, or express emotional dissatisfaction. It's important to show your studious and self-motivated side as much as possible. The interviewer will document their impression of you, including your strengths and weaknesses. Therefore, even if the technology does not meet the requirements, try to show the advantages of the character.

Ali interview process

Interviews are generally four to five, mostly phone interviews. The HR interview is the last round of interviews, so as long as you survive the previous technical interviews, it is generally OK. The first round is to examine the foundation, and the second round begins to examine the project, the ability of communication and expression. There may be programming in the third and fourth rounds, requiring on-site coding, or offline completion of a designated project. The level of the interviewer is between p6-p9, which generally increases as the interview process progresses. After the technical interview is passed, it is the HR interview. This round mainly examines the values. After all the interviews, there is a long wait, during which there will be a physical examination, a background check, and then an offer will be issued. This process will take a month, which is relatively long. It should be noted that during the interview process, you must ensure honesty, and you must not cheat at all. Because once a lie is discovered during the background check, not only will the offer be cancelled, but it will also be recorded in the talent pool. Another point is that you can't make an appointment for an interview at will, and this will also be recorded permanently. The process of each interview will be recorded in detail in the talent pool, so try not to leave blemishes that will affect future interviews.

The above two students are the two students led by James. The two students have interviewed and then wrote a summary. I will share it with you again.

So why are these two students able to interview Ali in early April? Some people said: "Maybe they are old fritters. Of course they can get interviewed with rich experience." Did you think that, according to what I asked James, both of them have 2-3 years of work experience, and the basics are medium.

Then I learned a systematic course system, and then went to the interview. If you also want to learn this systematic course system, then I recommend you an exchange learning group: 697579751, which will share some videos recorded by senior architects: Spring, MyBatis, Netty source code analysis, high concurrency, high The principles of performance, distributed, microservice architecture, and JVM performance optimization have become a must-have knowledge system for architects. You can also receive free learning resources, which have benefited a lot at present. The following course system diagram is also obtained in the group. The picture is not high-definition enough, you can get high-definition pictures by adding a group, group: 697579751

Systematic system diagram

1. Source code analysis