A collection of Java-based questions collected from 1.6W interviewers (knowledge brain map included)

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Basic Basics

1. Object-oriented features

2, final, finally, finalize the difference

3. What is the difference between int and Integer

4. The difference between overloading and rewriting

5. What is the difference between an abstract class and an interface?

6. The use and realization of reflection

7. Talking about the scene and implementation of custom annotations

8. The difference between the GET and POST methods of HTTP requests

9. Difference between session and Cookie

10. Session Distributed Processing

11. JDBC Process

12. MVC Design Idea

13. The difference between equals and = =

Collection

1. List and Set differences

2. List and Map differences

3. Difference between Arraylist and LinkedList

4. Difference between ArrayList and Vector

5. The difference between HashMap and Hashtable

6, HashSet and HashMap differences

7. The difference between HashMap and Concurrenthashmap

8, HashMap work principle and code implementation

9, Concurrenthashmap work principle and code implementation

Thread

1, the way to create threads and implementation

2. What is the difference between sleep (), join (), yield ()

3, talk about Countdownlatch principle

4, talk about Cyclicbarrier principle

5, talk about Semaphore principle

6, talk about Exchanger principle

7, talk about Countdownlatch and cyclicbarrier difference

8. ThreadLocal Principle Analysis

9, the realization principle of the thread pool of speaking and talking

10, thread pool of several ways

11, the life cycle of the thread

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Lock mechanism

1, talk about thread safety issues

2. The principle of volatile implementation

3, Synchronize realization principle

4. The difference between synchronized and lock

5. CAS Optimistic Lock

6. ABA problem

7. Optimistic locking business scenarios and implementation methods

Core piece data storage

1. MySQL Index Usage Precautions

2, talk about anti-pattern design

3, talking about the sub-Library and the design of the table

4. Distributed dilemma and countermeasures brought by sub-database and sub-table

5, talk about the way of SQL optimization

6. The deadlock problem encountered by MySQL

7. InnoDB and MyISAM of storage engine

8, the principle of database indexing

9, why to use B-tree

10. The difference between a clustered index and a nonclustered index

11, limit 20000 load very slow how to solve

12, choose the appropriate distributed primary key scheme

13. Choose the right data storage solution

14. ObjectId Rules

15. Talk about MongoDB usage scenarios

16. Inverted Index

17, chat ElasticSearch use scene

Cache usage

1. What are the types of Redis

2. REDIS internal structure

3. Talk about Redis usage scenarios

4. Redis Persistence mechanism

5. How to make Redis persistent

6. Redis Cluster scheme and implementation

7. Why is Redis a single thread

8. Cache crashes

9. Cache Demotion

10. The rationality of using cache

Message Queuing

1. Usage scenarios for Message Queuing

2, the message of the re-issued compensation solution ideas

3, the power of the message to solve the idea

4, the message of the accumulation of ideas to solve

5. How to implement Message Queuing

6, how to ensure the order of the message

Frame article Spring

1. What is the difference between beanfactory and ApplicationContext?

2. Spring Bean life cycle

3. How the Spring IOC is implemented

4, say Spring AOP

5. Spring AOP Implementation principle

6. Dynamic Agent (Cglib and JDK)

7, Spring Transaction Implementation mode

8, Spring transaction underlying principle

9. How to customize the annotation implementation function

10. Spring MVC Run Process

11. Spring MVC START process

12, Spring's single example realization principle

13. What design patterns are used in the Spring framework

14. Other Spring Products (srping Boot, Spring Cloud, Spring secuirity, Spring Data, Spring AMQP, etc.)

Netty

1. Why Choose Netty

2, talk about business, Netty of the use of the scene

3. Native NIO has epoll bug in JDK version 1.7

4. What is TCP sticky/unpacking

5, the solution of the TCP sticky packet/unpacking

6. Netty Threading Model

7. Say 0 copies of Netty

8, Netty internal execution process

9, Netty re-connected implementation

Micro-service Micro-service

1, the front and rear end separation is how to do

2, micro-service which framework

3. How do you understand the RPC framework

4, talk about the implementation of RPC principle

5, talk about the principle of the realization of Dubbo

6. How do you understand RESTful

7, talk about how to design a good API

8, how to understand the power of the RESTful API

9, how to ensure the power of the interface

10, say CAP theorem, BASE theory

11, how to consider the data consistency problem

12, say the final consistency of the implementation plan

13. What do you think of micro services

14. The difference between microservices and SOA

15. How to split the service

16. How to manage database in micro-service

17. How to deal with the chain call exception of micro-service

18, for fast tracking and positioning problems

19, micro-service security

Distributed

1. Talk about the use of distributed scenarios in business

2. Session Distributed Program

3. Distributed lock Scene

4, distribution is the implementation of the scheme of locks

5. Distributed Transaction

6. Algorithm and implementation of cluster and load balancing

7, talking about the sub-Library and the design of the table

8. Distributed dilemma and countermeasures brought by sub-database and sub-table

Security & Performance Security issues

1. Security elements and STRIDE threats

2. Guard against common Web attacks

3, service-side communication security attack and defense

4. Analysis of HTTPS principle

5. HTTPS downgrade attack

6. Authorization and authentication

7. Role-based access control

8. Data-based access control

Performance optimization

1. What are the performance indicators?

2. How to identify performance bottlenecks

3, the performance tuning common means

4. How do you perform performance tuning in your project?

Demand analysis of engineering articles

1. How do you understand and split the prototype requirements?

2. Talk about your understanding of functional requirements

3. Talk about your understanding of non-functional requirements

4. What interaction and improvement suggestions do you make for your product?

5, how do you understand the user pain point

Design capabilities

1. Talk about the UML diagram you used in your project

2. How do you consider the component

3, how do you consider the service of

4. How do you conduct domain modeling

5. How do you divide the boundaries of a domain

6. Talk about the domain modeling in your project

7, talk about the outline design

Design Patterns

1. What design patterns are used in your project?

2, talk about the use of the common open source framework design pattern Analysis

3. Talk about your understanding of design principles

4. Design concept of 23 design modes

5, the similarities and differences between design patterns, such as the difference between the strategy mode and the state mode

6, the combination of design patterns, such as the strategy mode + Simple Factory model practice

7, design mode performance, such as the singleton mode which performance is better.

Business Engineering

1. How the front-end separation in your system is done

2, talk about your development process

3. How do you communicate with the team?

4. How do you conduct code review

5. Talk about your understanding of technology and business

6. Talk about the Exception you often encounter in the project

7, say that you encountered in the project feeling the most difficult bug, how to solve

8, say that you encountered in the project the deepest impression of difficulties, how to solve

9. What do you think are the deficiencies in your project?

10, whether you have experienced CPU 100%, how to troubleshoot and solve

11. Have you encountered memory OOM, how to troubleshoot and resolve

12. Talk about your practice of agile development

13. Talk about your practice of developing operation and maintenance

14, the introduction of the work of one of their most valuable project, and the role in the process

Soft power

1. Tell me about your highlights

2. Tell me what book you are reading recently

3. Talk about the technical books that you think are most meaningful

4. What to do after work

5, talk about personal development direction of thinking

6, say what you think the service-side development engineer should have the ability

7, say what you think the architect is, what the architect does

8. Talk about the technical experts you understand

End-of-text benefits

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Summary of Java surface questions collected from 1.6W interviewers (with knowledge brain map)