Preface
2020 is finally ushering in the last two months. In this year, the whole world is unstable, surrounded by the epidemic, and gradually healed and immunized. Although the country seems to be no different from usual, it is not aware of the economic impact. How many years back? Companies large and small are facing bankruptcy or bankruptcy. For us in the workplace, it is undoubtedly a fatal blow. Well, back to the topic, as a JAVA blogger, let’s look at the current situation of JAVA~
This year, many people have switched from Java to other industries, and many people have squeezed into this market to get a share. Year after year, year after year. Of course, the market demand for Java programmers is still relatively large, and there are many directions for promotion of Java jobs, which brings opportunities for many people. But on the other hand, there is a shortage of high-level talents. Many programmers with work experience cannot meet the recruitment requirements of big companies. Compared with Ali, how far are you from high-level talents?
How to learn? Two tips
First, assess your self-study ability.
Second, find effective learning guidelines.
Today, I will provide you with some real questions from this year’s major factory. On the one hand, it can help friends who are preparing for the interview. On the other hand, because I am preparing the real interview questions of the major factory at three levels of beginner-intermediate-advanced, there are small partners in need You can also try your level to see which rank you are in? Get complete interview information, follow + forward + private message [real question] , share it with you for free~
Alibaba Cloud-Java Intern/Junior
The difference between List and Set
How does HashSet guarantee non-repetition
Is HashMap thread-safe? Why is it not thread-safe (it is best to draw a picture to show that it is not safe in a multi-threaded environment)?
HashMap expansion process
The difference between HashMap 1.7 and 1.8, explain what optimizations have been made in 1.8, and how?
Four references to objects
Three ways to get reflection in Java
Java reflection mechanism
Arrays.sort and Collections.sort implementation principles and differences
Cloneable interface implementation principle
Exception classification and handling mechanism
The difference between wait and sleep
How the array is allocated in memory
Answer display:
Baidu-Java Intermediate
What is the difference between BeanFactory and ApplicationContext
The life cycle of Spring Bean
How to implement Spring IOC
Talk about Spring AOP
Spring AOP implementation principle
Dynamic proxy (cglib and JDK)
Spring transaction implementation
The underlying principle of Spring transaction
How to customize annotations to implement functions
Spring MVC running process
Spring MVC startup process
Spring's singleton implementation principle
What design patterns are used in the Spring framework
Why choose Netty
Talk about the usage scenarios of Netty in business
Native NIO has an epoll bug in JDK 1.7
What is TCP sticking/unpacking
TCP sticking/unpacking solution
Netty thread model
Talk about Netty's zero copy
Netty internal execution process
Answer display:
Ant Financial-Java Advanced
Question 1:
1. What has changed from jdk1.7 to jdk1.8 Map (underlying)?
2. ConcurrentHashMap
3. What is the difference between parallel and concurrency?
4. What happened to the java virtual machine from jdk1.7 to jdk1.8?
5. If you were asked to design a middleware by yourself, how would you design it?
6. What is middleware?
7. Have you ever used ThreadLock, tell me what it does?
8. What is the difference between Hashcode() and equals() and ==?
9. In mysql database, under what circumstances are indexes set up but not available?
10. Will mysql optimize, mycat sub-database, vertical sub-database, horizontal sub-database?
11. Distributed transaction solution?
12. Will sql statement optimize, tell me what you know?
13. Have you understood the storage engine of mysql?
14. Red-black tree principle?
Question 2:
1. Talk about three kinds of distributed locks?
2. The realization principle of redis?
3. Redis data structure and usage scenarios?
4. What kinds of redis clusters are there?
5. Codis principle?
6. Are you familiar with the financial business? Bookkeeping business? Ant clothing has requirements for this part.
Answer display:
Alright~ After the show is over, maybe I'm a bronze or a king? Get the complete interview information, Sanlian + private message [real question] or see below , share it with you for free~
Some time ago, while chatting with group friends, I sorted out some different types of interview questions they saw this year, so I have the following interview question set, and share it with everyone~
Basics
JVM articles
MySQL articles
Redis articles
spring
Operating system
Multithreading
Data structure
Network articles
Does it feel useless after reading it~
It’s okay, I’m never late to study~ Get it from me
Sanlian + private message [real title] or scan the following , share it with you for free~
