You need to know Java interview summary large share

2020 Year of the Rat is a good start, we all know that ushered in the outbreak, causing everyone to work from home, some people barely hold back bad. Some small and medium enterprises are also faced unable to pay wages, our year-end awards nor forthcoming, gold and three silver four good opportunities interview delayed, they are also worried, do not know how to come after the development. The Java summary for everyone to share

ZooKeeper

1. CAP theorem

2. ZAB agreement

3. Leader election algorithms and processes

Redis

1. Redis application scenarios

2. Redis data types supported (compulsory)

3. zset jump table data structure (compulsory)

4. Redis data expiration policies (compulsory)

5. LRU expiration policies specific implementation of the Redis

6. How to solve the avalanche Redis cache, the cache penetrating questions

7. Redis persistence mechanism (compulsory)

8. Redis pipeline pipeline

Mysql

1. The basic elements of the transaction

2. Transaction isolation level (compulsory)

3. How to solve the problem of concurrent transactions (dirty reads, phantom reads) (compulsory)

4. MVCC multi-version concurrency control (compulsory)

5. binlog, redolog, undolog are what, what role

6. InnoDB row locks / lock table

7. Myisam and the difference between innodb, when selecting myisam

8. Why B + tree as an index structure (compulsory)

9. B + tree index leaf nodes of the things which can be stored (compulsory)

10. Queries do not go at what time index (compulsory) (anticipated)

11. How to optimize sql

12. How to explain the sql is parsed

13. order by principle

JVM

1. Runtime data area (memory model) (compulsory)

2. Garbage collection (compulsory)

3. Garbage collection algorithm (compulsory)

4. Minor GC and Full GC trigger conditions

5. GC中Stop the world（STW）

6. Characteristics and differences of each garbage collector

7. Parent delegation model

8. JDBC and parents delegate model relationships

9. JVM locks and lock expansion process optimization

Java foundation

1. HashMap and ConcurrentHashMap difference (compulsory)

2. ConcurrentHashMap data structure (compulsory)

3. High concurrency HashMap ring is how to generate

4. volatile action (compulsory)

5. How to guarantee the atomicity Atomic class (CAS operation) (compulsory)

6. The difference between synchronized and Lock (compulsory)

7. Why use a thread pool (compulsory)

8. The core thread pool ThreadPoolExecutor parameters (compulsory)

9. ThreadPoolExecutor workflow (compulsory)

10. How to control the thread pool thread priority

11. How to communicate between threads

12. Boolean accounted for a few bytes

13. jdk1.8 / jdk1.7 what features are added separately

14. Exception和Error

Spring

1. Implement Spring's IOC / AOP's (compulsory)

2. Dynamic proxy implementation (compulsory)

3. Spring how to resolve a circular dependency (level three cache) (compulsory)

4. Spring post-processor

5. How @Transactional Spring's implementation (compulsory)

6. Spring transaction propagation level

7. Contact and the difference between BeanFactory and the ApplicationContext

other

1. How limiting high concurrency system implementation

2. Highly concurrent systems design spike

3. How to Load Balancing design

Interview feelings and Evaluation

In addition to foreign companies, the best experience is Ali. Absolutely stand out, whether it is professional level of the interviewer or the interviewer involved in the attitude of interviewers are fully prominent in other companies. Very respected person, and will guide me to make the right answer, Ali is the only HR is very strong, always have a veto. And some companies interviewer will deliberately mislead you, trying to make you say the wrong answer, and some extremely arrogant attitude, people feel very respected people. Here criticized interview to experience the worst of the two companies: the US group and Boss straight employed. Foreign words, experience is very good. Microsoft is the English side, Amazon is not. Maybe are based algorithm based, in addition to Microsoft's algorithm also talked operating systems and computer networks, Amazon talked for a long time project details.

Last wish is about to quit the job and already we can find a good job, not a winter insurmountable without a spring would not be coming! ! !

Above are some of my own thoughts, to share out the welcome to correct me, the way to find a wave of concern inside information you click [Java] small partner after the attention I can receive free ~