Java face question

Basic topics

1. The state of the Java thread
2. Differences between processes and threads, how interprocess communicates, and how threads communicate with each other
3. What is the data structure of HashMap? How it is implemented. The difference between the Hashtable,concurrenthashmap and the
4. The difference between a cookie and a session
5. What's the use of indexes? How do I build an index?
6. How is ArrayList implemented, the difference between ArrayList and LinkedList? ArrayList how to achieve capacity expansion.
7. The Equals method implements
8. Object oriented
9. Thread state, what's the difference between blocked and waiting
10. How the JVM loads bytecode files
11. JVM GC,GC algorithm.
12. What happens when the full GC is present, and what happens to the Yong GC.
13. JVM Memory model
14. Java Runtime Data area
15. How transactions are implemented

Technical depth

1. Have you seen the JDK source code, see the class implementation principle is what.
2. HTTP protocol
3. TCP protocol
4. Consistent hash algorithm
5. How the JVM loads bytecode files
6. How the ClassLoader unloads bytecode
7. The difference between IO and NIO, NIO benefits
8. Java thread Pool Implementation principle, KeepAliveTime parameters such as the role.
9. HTTP connection Pooling Implementation principle
10. Database connection pooling Implementation principles
11. How the database is implemented

Technical framework

1. See what open source framework of source code
2. What are the pros and cons of using Redis,redis? How does redis achieve capacity expansion?
3. Netty is how to use the thread pool, why use it so
4. What are the pros and cons of using spring,spring?
5. Spring's IOC container initialization process
6. Spring's IOC container implementation principle, why beans can be found through byname and Bytype
7. Spring AOP Implementation Principles
8. How the message middleware is implemented, and what are the technical difficulties

System architecture

1. How to build a highly available system
2. Which design patterns can increase the scalability of the system
3. Introduces design patterns such as template mode, command mode, policy mode, adapter mode, bridging mode, decoration mode, observer mode, state mode, visitor mode.
4. Abstract ability, how to improve the efficiency of research and development.
5. What is high cohesion low coupling, please give examples of how to achieve
6. What situation with the interface, what condition with the message
7. If AB two systems depend on each other, how to release dependencies
8. How to write a design document, what is a directory
9. What scenarios should be split system, what scenario should merge system
10. What is the difference between the system and the module, and what scenarios are used

Distributed Systems

1. Distributed transactions, two-phase commit.
2. How to implement a distributed lock
3. How to implement distributed session
4. How to guarantee the consistency of messages
5. Load Balancing
6. Forward proxy (client proxy) and reverse proxy (server-side proxy)
7. CDN Implementation Principle
8. How to improve the system's QPS and throughput

Actual combat capability

1. Have you dealt with the problem on the line? There is a memory leak, a CPU utilization level, and how the application is handled without responding.
2. Have you encountered any technical problems in the development? How to solve the
3. If there is a billions of whitelist, high concurrent queries are required daily during the day and need to be updated at night to design this feature.
4. How Sina Weibo is enabling Twitter to Subscribers
5. How Google returns the search results to the user within a second.
6. 12306 how the booking system of the website is implemented, how to ensure that no ticket is not oversold.
7. How to implement a second kill system, to ensure that only a few users can buy a product.

Soft power

1. How to learn a new technology, such as how to learn Java, focus on learning what
2. What new technologies are in focus
3. How to deal with a lot of work tasks and very miscellaneous
4. How Project Latency is handled
5. It's not the same as my colleagues ' design ideas.
6. How to ensure the quality of development
7. What is career planning? Short term, what is the long term goal
8. What is the planning of the team?
9. To introduce myself from work to the present and grow there

Java face question