preface

2020 finally ushered in the last month, this year, the whole world is unstable, surrounded by the epidemic, gradually cured and immune, although the domestic look and usual little difference, but for the impact of the economy, I do not know how many years back? Large and small companies facing bankruptcy or bankruptcy, for us in the workplace, is undoubtedly a fatal blow, ok, back to the theme, as a JAVA blogger, look at the recent situation of JAVA ~

This year has seen a lot of people moving from Java to other industries, and a lot of people trying to get a piece of the market. Year after year, year after year. Of course, Java programmers are still in high demand, and there are many opportunities for advancement in Java jobs. But on the other hand, senior talent shortage, many even have work experience of programmers are not up to the requirements of large factory recruitment, compared to Ali, see you from senior talent still a few steps?

How do you learn? Two tips

First, assess your self-study ability.

Second, find effective study guides.

Today we provide some of this year’s dachang real questions, on the one hand, can help the friends who are preparing for the interview, on the other hand, because I prepared is the primary – intermediate – advanced three levels of dachang real questions, so you can try your own level, see yourself in which section?

Need to get the words after a key three even trouble, click hereAs a developer, you can’t miss this core knowledge to improve your skills

Ali Cloud — Java Intern/Beginner

Difference between a List and a Set

How is a HashSet guaranteed not to repeat itself

Is HashMap thread safe, and why not?

Expansion process of HashMap

What is the difference between HashMap 1.7 and 1.8?

Four kinds of references to objects

Java gets reflection in three ways

Java reflection mechanism

Arrays.sort and collections. sort

Cloneable interface implementation principle

Exception classification and handling mechanism

The difference between ‘wait’ and ‘sleep

How are arrays allocated in memory

Answer display:

Baidu – Java intermediate

What’s the difference between BeanFactory and ApplicationContext

The life cycle of Spring beans

How is Spring IOC implemented

Tell me something about the Spring AOP

Implementation principles of Spring AOP

Dynamic Proxy (Cglib and JDK)

Spring transaction implementation

Underlying principles of Spring transactions

How do I customize the annotation implementation

Spring MVC runs the process

Spring MVC startup process

Spring’s singleton implementation principles

What design patterns are used in the Spring framework

Why Netty

This section describes the Netty application scenario

The native NIO has an epoll bug in JDK 1.7

What is TCP sticky/unpack

TCP sticky/unpack solution

Netty threading model

Talk about Netty’s zero copy

Netty internal execution process

Answer display:

Ant Financial — Java Advanced

Topic 1:

1. What has changed between JDk1.7 and JDk1.8 Map (bottom level)?

2. ConcurrentHashMap

3. What is the difference between parallelism and concurrency?

4. What changes have taken place between jdk1.7 and jdk1.8 Java virtual machines?

5. If you were asked to design middleware yourself, how would you do it?

6. What is middleware?

7. Have you used ThreadLock before? What does it do?

8. What is the difference between Hashcode () and equals ()?

9. When is an index set in a mysql database but cannot be used?

Mysql optimization will not,mycat branch, vertical branch, horizontal branch?

11. Distributed transaction solution?

12 SQL statement optimization will not, say what you know?

Mysql storage engine

14. Red black Tree principle?

Topic 2:

1. What are the three distributed locks?

2. How does Redis work?

3. Redis data structure, usage scenarios?

4. What are the types of Redis clusters?

5. Codis principle?

6. Are you familiar with financial business? Bookkeeping? Ant Financial has requirements for this part.

Answer display:

Good ~ show finished, probably estimate oneself is bronze or king?

Need to get the words after a key three even troubleClick here toYou can get it for free

Some time ago, while chatting with group friends, I sorted out some different kinds of interview questions they saw this year, so I have the following set of questions, and also share with you ~

Based on article

The JVM article

MySQL article

Need to get the words after a key three even troubleClick here toYou can get it for free

Redis article

The spring piece

Operating System

Need to get the words after a key three even troubleClick here toYou can get it for free

Multithreaded piece

Data structure

Network article

Finally, the final need to get the words to trouble one key three after scanning add small assistant VX: