A monthly salary of 3W + is very common in BAT and other first-line large factories. It is usually a middle or senior engineer position.

The post ranks are P6-P7 in Ali, 2-1 in Byte, T6 in JINGdong and 2-3 in Meituan. Most of the post-90s, or even post-95s, can reach this level if they pass the technical test.

After learning technical development, we hope to enter a big factory very much, but it is not easy to enter a big factory through layers of interviews. Today, I have summarized a set of Java interview questions of big factory and attached answers, hoping to be helpful to your friends.

1. Java Basics

One side attaches great importance to basic knowledge, will focus on collection, multithreading, IO, exception, reflection, annotation, serialization, deserialization and other knowledge in detail.

Then there are networks and data structures, and data structures will also look at red black trees, balanced binary trees and so on.

2. Middleware framework

At present, most of the big factory’s assessment is about the direction related to the spring family barrel.

For example, the startup process, the bean initialization process, the life cycle, how to solve the cycle dependency problem, etc.

Cache, Redis, Memcache, or at least one of the others you are familiar with. You can understand the underlying data structure, implementation principles, and general usage.

Database, Mysql or Oracle to be familiar with a kind of, know the implementation of database and table, database backup, database transaction, index, lock mechanism, etc.

MQ is also a key knowledge, generally will ask messages idempotent, transactional implementation, how to ensure that no messages are lost, etc., to be familiar with at least one message queue, understand the principle.

3

Usually the interviewer will give you a specific scenario to do, and if it’s architectural design, it’s usually high concurrency. If it is database design, generally see how you design data to facilitate the query.

  • Theory of the topic

Theory questions will most likely test your understanding of commonly used distributed theory. Conformance protocols, distributed CAP, Base theory, service degradation, fuses, restful interfaces, etc.

  • Experience in project

When I talked with my friends, I found that project experience was really a key point, which was mentioned in almost every round of interview. The second and third interviews focused more on project experience and project extension.

If you can’t explain your project clearly, the interview is going to be cold, so be sure to think about your project, what difficulties it had, what problems it solved, how it changed the structure, why it changed, and what the result was.

  • Handwritten code

Code assessment is to enter the big factory need to prepare, have time to brush more questions, absolutely no harm.

So, judging from the experience of friends, big factory interviews focus on basic skills and project experience. 支那

Therefore, in the process of Java learning, we must conscientiously study and constantly knock on code, carry out project combat, and master Java skills. It is not a problem to enter Dachang.