My diary interview [Java]

background

In the old club for five years, a total of seven years of work the whole experience of both companies. 2019- departure 10-31 days. Smaller size of the company, the project is not pressure, non-985/211 graduation, college entrance examination, a computer professional. Target: medium and large companies, it is best manufacturers, hey, but no hope, after all, the background is not very good.

ready

Resume writing, 7-12 points home from work every day to see the video, brush the blog, watch face questions. Learning content: JavaGuide , "a certain time" The series, "a certain classroom" learning video. Ready content: Java-based, collection, thread pools, locks, MySQL index, transaction, Spring and so on.

2019-10.31 Thursday

Mention leaving already for two days, and today signed the boss, do the separation procedures, "so straight recruits" to upload your resume, refresh your resume. "A Supply Chain East" called and asked me to ask whether the entrance examination of undergraduate education, about my interview tomorrow afternoon. But he can be considered a giant, that no interview experience Zaban, was very disturbed, it does not matter, start filling it! Hey, there is news, I saw my classmate sent me a shot, he had to brush my resume, he said, help me push inside, the heart is still very excited. Push within the company: "taxi"

2019-11-01 Friday

Get up at half past five in the morning, and start watching videos, brush material, preparing for interviews, until 12:00, did not eat. Companies too far, in Yizhuang, it takes two hours to get to, out of the subway, greeted by their building. Find the department, gave Zhang interview questions.

HashMap, HashTable, ConcurrentHashMap similarities and differences?
Spring's init-method, destroy-method of implementation?
Several said that the way to achieve power, etc.?
Said the implementation of several distributed lock?
There is a List collection, multi-threaded computing the sum, say your ideas and to use the framework.
An open topic, the number of triangles

Done the subject, I feel relatively OK, to an interviewer, about thirty.

Self introduction
Tell us about the project
JVM memory model
MySQL transaction isolation underlying implementation?
MySQL index tell us about?
What should pay attention to the index hit?
List Go heavy, hand-written code, examine the basis

Two faces: department head

Simple chat, introduce business team, what do you want to ask? Wait for notification. (Said yes in the "taxi" push it, how not to call me Yeah, well, not too might resume.)

Summary: MySQL transaction isolation underlying implementation details still need more add, JVM see more details.

Received "a certain rent" company for an interview invitation. Monday afternoon face, just ready in preparation for Saturday and Sunday.

2019-11-04 Monday

The way to the subway company building. Hello to interview. Received a face questions, he came to the third floor lounge, with a lot of people like the vegetable market. I rub the competition so much pressure ah, looked at the face questions, not a lot of, well, do not do, let's go. To have come, try chanting. Started topic.

String new String relations ==, equals
Two lists intersect, find the intersections
Three threads print order ABC
If aab, aba equal to two strings, it is determined whether the same
Painting about RPC architecture diagram

Side: one to speak more softly technology officer.

Self introduction
String, new String This question why so choose? the reason?
Talk about the project
Handwriting a singleton
JVM memory model, JAVA stack can allocate objects?
Talk about class loading process, the parent delegation model source code read it? introduce
Stack overflow under what circumstances?
Stack frame tell us about?
MySQL Index understand it? Painting it?
From a business point of view, how to design MySQL database? What optimization point there?
Garbage collection to understand it? introduce?
Talk about the principle of AOP? Cglib the agency for final approach?

The interviewer said to me: I feel OK, you wait a minute, we lead a meeting, let HR inform you that two faces another day of it. : Well, go home.

Students micro letter: HR us to call you yet? : No, I can give you about him.
HR: Hello, in order not to waste time, about your telephone interview. (Students intervention)
HR: Hello, Friday directly to the company for an interview. . . .

2019-11-05 Tuesday

Live in peace, to help my cousin's friend's driver's license buckle 9 points. . . Afternoon to a company interview, the interviewer did not receive the results of a telephone, the security would not let me ask, well, leave it.

2019-11-06 Wednesday

"A certain rent" re-examination. The interviewer was very young, two years older than me, people have a R & D Manager, and look at me. Hey. . . .

RPC framework of the project why not?
RPC understand it? , Draw a flow chart of what?
RPC and HTTP protocols What is the difference?
Long physical connection is real do?
Tell us about the project?
MQ message is lost how to do? Message is atomic right?

Three sides: R & D Director

Lock tell us about? What?
Thread blocks from the operating system point of view tell us about?
Other not remember

Four in the afternoon: Technical Director

HTTPS process
What do you think you still lack?
How to learn?
Bullsh, line, sign, hired

HR talk offer, go home myself.

2019-11-07 Thursday

"So excellent fresh" afternoon, looking to find the building for a long time. The company several layers, I rub, not seen at this parade. Upstairs Wait a minute, did not face questions.
one side:

How to split your project? Why do you split?
How to ensure service availability?
MySQL hung up how to do? (Hang hung up, very ashamed, the company did not achieve high availability database ....)
Project experience a little bit worse ah, do not ask your Internet project problems
Talk about WebSocket protocol
Talk about the HTTPS protocol

Two faces:

SpringBoot know? And Spring difference?
If you want to do custom development, how to do?
@Conditional say something
Propagation mechanism affairs?
Talk about MySQL indexing?
Re-enter lock principle? (State, AQS)
Split service, service management has to understand it?

HR: Simple chatted, why not leave for five years? You rarely see this ah. There are a sector leader interviews, you go back, the phone surface.
Notified evening, Friday 6:00 telephone interview.

2019-11-08 Friday

The past has finally come, to face the ultimate BOSS. Fortunately, however, do not take the subway, and the morning saw a few videos, prepare a little, 12:00, take a bath, pack up. Cycling departure, feeling very ill at ease. Ride to the place, the company LOGO greeted two buildings. HR to call reception, upstairs, waiting for a while, a young interviewer coming.

Design a spike system, talk about your ideas. (I rub !!!)
How to design current limit?
Inventory how deduction? decrby can do?
Stock deduction fails how to do?
Painting about the project structure?
a, b, c joint index, a = 1, b = 1, c> 1 index can hit it? a = 1, b> 1, c = 1 hit can index it?
JVM heap talk about? Full GC triggered scene of what?
Talk about the G1 garbage collector? How old's, the young generation distribution?
Redis lock error how to do?
Redis deductions stock have a problem how to do?
Design of a transfer system? A-> B switch 100, there is no idea?
What Redis persistent way?
Redis data will be stored to disk do?
Redis Why so fast?
Linux Statistics top10 IP access logs, which commands to use? (will not)
Linux yourself what commands used it?
How to view the log Dump? How produced? What order?
A thread pool, 10 core, 100 maximum number of threads, queues 100, 10000 call back request, describe how the thread pool to run? He refused how do?
Look at the basics of it, String new String difference? (== equals)

:( two faces on one side and asked several questions repeat, victims I spoke again)

What do you think the project difficulties? (Event Registration overcrowding, think of the spike)
How to deal with spike scene?
You can use Redis decrby inventory deductions do it? How to do? (Atomicity can be guaranteed lua)
lua too, have another plan?
How to stock recovery?
Prevent oversold does not work, orders for non-payment of how to deal with?
How username and password to prevent theft? (Js encryption, not, or can crack, oh, https ....)
Https talk about the process?
There had to know what asymmetric encryption algorithm? Symmetric encryption algorithm do?
c, b, a problem index, c = 1, b = 1, a = 1 index can hit it? c> 1, b = 1, c = 1 hit can index it? why?
How to review service differentiation module? (BizId)
A business off the hook database how to do? (Sub-libraries, split service, deployed separately, what else? MQ)
Learn limiting it? Downgrade? Well, you have no contact, I do not ask. (ORZ)
Linux Statistics top10 IP access logs, which commands to use? (will not)
Talk about your understanding of the structure of HashMap, how to do the same if Key, or the list is inserted after the forward runs? Red-black trees?
Which Linux command used? (Mkdir, ll, and so on .... linux is really my weakness, later to be catching up.)
12233445, how to determine the index position 3? (Counting statistics, O (N) O (N), is there a better way? Cycle it. (The correct answer dichotomy that I mentioned, but the idea was wrong, was granted a meal)
How do GIT team development? If you do not have a feature on the line how to do it?
If the package maven conflict, not solve what problem? How to resolve package conflicts?
Design at Dubbo thread pool? Every request 50ms 200 QPS, the client 500ms timeout, how to design? Directly into the 200 requests it? Queue how much? How much thread pool? (The answer is not good)
Integer a1 = 10000 Integer a2 = 10000, They == results? How can equal it? (Equals, == compares reference to address, investigate Integer cache)
Integer a1 = 100 Integer a2 = 100 it? Parameters can be set right? How do I set?

Department boss face:

You are certain students, right? (Roommate)
Talk about future plans?
Technology Growth? What options do business there?
Not just look at technology, to be familiar with the business
If the DB to hang up with ways in which to solve? (I said something I think the scheme, but clearly not .. after all, no contact, we can only own understanding)
How statistics QPS? There is no framework for understanding the market? How to implement the principle of it?
They are asked to ask and talk about it non-technical
Wait, let me find you HR.

HR side:

Reason for leaving?
Five years how to leave out?
expected salary?
Monday and other news.

And students simply chatted. Students say that I can answer, but less experience. (Hey, small companies small volume of business, indeed suffer). Take it easy! I said, I have had the opportunity to interview contentment! ! ! Otherwise, I certainly can not resume before.

to sum up

Before the interview you sure you want to do more preparation, but actual combat experience, then better, no wonder manufacturers are more manufacturers jump easier. Small companies do not be discouraged, some companies do not look at the project and see your understanding of high concurrent projects, even if they did not do, have their own programs can be. The foundation must be solid, not just the back theory, insight, understanding the deeper the better, although the interview made rockets, work tighten the screws, you have the ability to build rockets afraid not tighten the screws yet?

Face a whole week, a total of four companies, the end result they can still acceptable. JVM, MySQL must master, the other to a solid foundation of knowledge, and to use the actual, or else no matter how much science theory, Linux operating system you want to study intensively, because fewer high concurrency scenarios own experience, the only traffic larger companies can learn.

In addition, information on the market, whether it is paid or non-paid really helpful for the interview, but if they have a good mix of projects, it is better, or else the interviewer did not ask law.

Do not ask me why I do not leave for five years, I do not know, is a good thing or a bad thing?

The whole face down, I felt ready barely passed, but still not good enough, you should be able to answer better, reminds me of a word, you could do better. So, remind ourselves not to waste any more time, more learning, more summary. Luckily, thanks to the students in the push again, thank you.

On 2019-11-08 21:02