The content of this document covers: Java, MyBatis, ZooKeeper, Dubbo, Elasticsearch, Memcached, Redis, MySQL, Spring, Spring Boot, Spring Cloud, RabbitMQ, Kafka, Linux and other technology stacks, a total of more than 1,000 interview questions.
Due to the excessive content of the document, only the following catalog parts are listed, and each knowledge point has more detailed content! Friends who need to get this interview document: after one click and three connections
Java concurrent programming
3.What is context switching in multithreading?
4. The difference between deadlock and livelock, and the difference between deadlock and starvation?
5. What is the thread scheduling algorithm used in Java?
6. What is a thread group and why is it not recommended in Java?
》7. Why use the Executor framework?
8. What is the difference between Executor and Executors in Java?
9.How to find which thread uses the longest CPU time on Windows and Linux?
10. What is an atomic operation? What are the atomic classes in the Java Concurrency API (atomic cla
11.What is the Lock interface in the Java Concurrency API?
12. What is the Executors framework?
13. What is a blocking queue? What is the implementation principle of a blocking queue? How to use a blocking queue to implement the producer-consumer model?
14. What are Callable and Future?
15. What is FutureTask? Use ExecutorService to start tasks.
16.What is the implementation of concurrent containers?
17. There are several ways to achieve multi-thread synchronization and mutual exclusion, what are they?
18. What are competition conditions? How do you discover and resolve competition?
19. How will you use thread dump? How will you analyze thread dump?
20. Why do we execute the run0 method when we call the start0 method, why can't we directly call the run0 method?
21. How do you wake up a blocked thread in Java?
22. What is the difference between CycliBarriar and CountdownLatch in Java?
23. What is an immutable object, and how does it help to write concurrent applications?
24. What is context switching in multithreading?
25.What is the thread scheduling algorithm used in Java?
26. What is a thread group and why is it not recommended in Java?
27. Why is it better to use the Executor framework than to create and manage threads using an application?
28. There are several ways to implement a thread in java?
29. How to stop a running thread?
30. What is the difference between notifyO and notifyAIl0?
31. What is a Daemon thread? What does it mean?
32.How does java realize the communication and cooperation between multiple threads?
33. What is a reentrant lock (ReentrantLock)?
34. When a thread enters a synchronized instance method of an object, its
Whether other threads can enter the other of this object
35. The understanding of optimistic lock and pessimistic lock and how to realize it, what are the ways to realize it?
36. What is the difference between SynchronizedMap and ConcurrentHashMap?
37. What applications can CopyOnWriteArrayList be used for?
38. What is thread safety? Is servlet thread safe?
39. What is the use of volatile? Can you explain the application scenarios of volatile in one sentence?
40. Why does the code reorder?
41. The difference between wait and sleep methods in java?
42. Implement blocking queues in Java
43. What happens if an exception occurs when a thread is running?
44. How to share data between two threads?
45. What is the difference between notify and noftifyAll in Java? 44. How to share data between two threads?
46. Why wait, notify and ntfifAll are so many
47. What is a ThreadLocal variable?
48. What is the difference between interrupted and isInterrupted methods in Java?
49. Why should the wait and notify methods be called in a synchronized block?
50. Why should you check the wait condition in the loop?
51. What is the difference between a synchronized collection and a concurrent collection in Java?
52. What is a thread pool? Why use it?
53. How to detect whether a thread owns a lock?
54. How do you get the thread stack in Java?
56.What is the function of the yield method in the Thread class?
57. What is the concurrency of ConcurrentHashMap in Java?
58.What is Semaphore in Java?
59. What is the difference between the submit0 and execute0 methods in the Java thread pool?
60. What is a blocking method?
61.What is ReadWriteLock in Java?
62. What is the difference between volatile variables and atomic variables?
63.Can the run 0 method of the Thread class be called directly?
64. How to pause the running thread for a period of time?
65. What is your understanding of thread priority?
Spring interview questions
1. General issues
1.1. What are the main features of different versions of Spring Framework?
1.2. What is Spring Framework? ......
1.3. List the advantages of Spring Framework.
1.4. What are the different functions of Spring Framework?
1.5. How many modules are there in Spring Framework and what are they?
1.6. What is a Spring configuration file?
1.7. What are the different components of a Spring application? .. .........
1.8. What are the ways to use Spring?
2. Dependency Injection (Ioc)
2.1. What is the Spring IOC container?
2.2. What is dependency injection?
2.3. How many ways can dependency injection be done?
2.4. Distinguish between constructor injection and setter injection.
2.5. How many types of I0C containers are there in spring?
2.6. Distinguish between BeanFactory and ApplicationContext.
2.7. List some of the benefits of loC.
2.8. Implementation mechanism of Spring loC.
3.1. What is a spring bean?
3.2. What configuration methods does spring provide?
3.3. Does spring support centralized bean scope?
3.4. What is the life cycle of the spring bean container?
3.5. What is spring's internal bean?
3.6. What is spring assembly.
3.7. What are the methods for automatic assembly?
3.8. What are the limitations of automatic assembly?
Spring Boot interview questions
1. What is Spring Boot?
2.What are the advantages of Spring Boot?
3. What is JavaConfig?
4. How to reload the changes on Spring Boot without restarting the server?
5. What is the monitor in Spring Boot? ....
6.How to disable Actuator endpoint security in Spring Boot?
7. How to run Spring Boot application on custom port?
8. What is YAML? ....
9.How to realize the security of Spring Boot application?
10. How to integrate Spring Boot and ActiveMQ?
11. How to use Spring Boot to implement paging and sorting?
12. What is Swagger? Have you implemented it with Spring Boot?
13. What is Spring Profiles?
14.What is Spring Batch?
15. What is a FreeMarker template?
16. How to use Spring Boot to implement exception handling?
17.Which starter maven dependencies did you use?
18. What is a CSRF attack?
19. What is WebSockets?
20. What is AOP?.
21. What is Apache Kafka?
22.How do we monitor all Spring Boot microservices?
Spring Cloud interview questions.
1. What is Spring Cloud?
2.What are the advantages of using Spring Cloud?
3. What does service registration and discovery mean? How does Spring Cloud implement it?
4. What is the significance of load balancing?
5. What is Hytrix? How does it achieve fault tolerance?
6. What is a Hystrix circuit breaker? Do we need it?
7. What is Netlix Feign? What are its advantages?
8. What is Spring Cloud Bus? Do we need it?
RabbitMQ interview questions
1. What is rabbitm...
2. Why use rabbitmq.
3.Scenarios using rabbitmq.
4. How to ensure that the message is sent to RabbitMQ correctly? How to ensure that the message is received
Cost the news?
5. How to avoid repeated delivery or repeated consumption of messages?
6. What is the transmission of the message?
7. How is the message distributed?
8.How to route the message?
9. How to ensure that the message is not lost?
10. What are the benefits of using RabbitMQ?
11. RabbitMQ cluster.
12. Disadvantages of ma
Kafka interview questions
1. How to get a list of topic topics...
2. What are the command lines for producers and consumers?
3. Is the consumer pushing or pulling?
4. Tell me about Kafka's method of maintaining consumption status tracking.
5.Talk about master-slave synchronization.
6. Why do I need a message system, can mysql not meet the demand?
7. What is the role of Zookeeper for Kafka?
8. What are the three types of transaction definitions for data transmission?
9. Kafka judgment-whether a node is still alive has those two conditions?
10. There are three key areas between Kafka and the traditional MQ messaging system...
11. Talk-talk about the three mechanisms of Kafka's ack
13. How to solve the problem of consumer failure and livelock?
14.How to control the location of consumption.
15. In the case of Kafka distributed (not stand-alone), how to ensure the order of messages
16.What is the high availability mechanism of Kafka?
17. How does Kafka reduce data loss
18. How does Kafka not consume duplicate data? For example, deductions are not allowed.
MyBatis interview questions
1. What is Mybatis? ....
2. The advantages of Mybaits:
3. Disadvantages of MyBatis framework:
4. Applicable occasions of MyBatis framework:
5. What is the difference between MyBatis and Hibemate?
6. What is the difference between #0 and $0?
7. What should I do when the attribute name in the entity class is not the same as the field name in the table? ....
8. How to write like statement in fuzzy query?.
9. Usually an Xml mapping file will write a Dao interface corresponding to it, please
What is the working principle of the Dao interface? Can the methods in the Dao interface be overloaded with different parameters?
10. How does Mybatis perform paging? What is the principle of the paging plug-in?
11. How does Mybatis encapsulate the sql execution result into the target object and return it? Which mapping forms?
12.How to perform batch insert?...
13.How to get the automatically generated (raw) key value?.
14. How to pass multiple parameters in mapper...
15. What is the use of Mybatis dynamic sql? The principle of execution? What are the dynamic sq!?
16. In the Xml mapping file, in addition to the common selectinsertlupdaeldelete, what other tags are there? .... .... ..
18. Why is Mybatis a semi-automatic ORM mapping tool? Where is it and fully automatic?
19.-One-to-one, one-to-many related queries?
20. MyBatis implementation-there are several ways for one? How to operate it?
21. MyBatis implementation-How do you operate in several ways?
22. Does Mybatis support lazy loading? If so, what is its implementation principle
23. Mybatis-level, second-level cache..
24. What is the interface binding of MyBatis? What are the implementation methods?
25. What are the requirements when using the mapper interface of MyBatis?
26. What are the several ways to write Mapper?
27. Briefly describe the operation principle of Mybatis plug-in and how to write a plug-in.
ZooKeeper interview questions
1. ZooKeeper interview questions?
2. What does ZooKeeper provide?
3. Zookeeper file system...
4. ZAB agreement?
5. Four types of data nodes Zno.e.... ...
6. Zookeeper Watcher mechanism-data change communication...
7. Client registration Watcher implementation...
8. Server-side processing Watcher implementation
9. Client callback Wartcer..._..
10. ACL permission control mechanism
11. Chroot features
12.Session management.
13. Server role
14. Server working status under Zookeeper
15. Data synchronization
16. How does zookeeper ensure the sequential consistency of transactions?
17.Why is there a Master in a distributed cluster?
18.How to deal with zk node downtime?
19. The difference between zookeeper load balancing and nginx load balancing...
20. What are the several deployment modes of Zookeeper?
21. The cluster requires at least a few machines, what are the cluster rules?.....
22. Does the cluster support dynamically adding machines?
23. Is Zookeeper's watch monitoring notification to the node permanent? Why is it so long...?...
24. What are the java clients of Zookeeper?
25. What is chubby, and how do you compare to zookeeper?
26. Talk about a few commands commonly used in zookeeper.
27. What are the connections and differences between ZAB and Paxos algorithms?
28. Typical application scenarios of Zookeeper
Dubbo interview questions
1. Why use Dubbo?
2. What are the layers of Dubbo's overall architecture design...
3. What communication framework is used by default, are there other options?
4. Is the service call blocking?
5.-What registration center is generally used? Are there other options?
6. What serialization framework is used by default, and what else do you know? ....
7. What is the principle that the service provider can achieve the failure kick-out?
8.Why doesn't the service launch affect the old version?
9. How to solve the problem of too long service call chain?
10. What are the core configurations?
11. What protocol does Dubbo recommend?
12. Can a service be directly connected to the same service in the case of multiple registrations? ....
13. Draw a flowchart of service registration and discovery?
14. How many solutions are there for Dubbo cluster fault tolerance?
15. Dubbo service is downgraded, what should I do if I fail to retry?
16.What problems did you encounter during the use of Dubbo?
17. How does Dubbo Monitor implement?
18. What design patterns does Dubbo use?
19. How is the Dubbo configuration file loaded into Spring?
20. What is the difference between Dubbo SPI and Java SPI?
21. Does Dubbo support distributed transactions?
22. Can Dubbo cache the results?
23. How is the service online compatible with the old version?
24. What are the packages that Dubbo must rely on?
25. What can the Dubbo telnet command do?
26. Does Dubbo support service downgrades? ...
27. How does Dubbo stop gracefully?
28. The difference between Dubbo and Dubbox?
29. The difference between Dubbo and Spring Cloud?
30. Do you know other distributed frameworks?
Elasticsearch interview questions.
1. How much do you know about elasticsearch, talk about your company's es cluster architecture, index building size, how many shards, and some tuning methods.
2. What is the inverted index of elasticsearch
3. What should I do if there is too much elasticsearch index data, how to tune and deploy.
4. How elasticsearch implements master election.
5. Detailed description-the process of indexing documents in Elasticsearch.
6. Detailed description-next Elasticsearch search process? ...
7. When Elasticsearch is deployed, what are the optimization methods for Linux settings...
8. What is the internal structure of lucence?
9. How does Elasticsearch implement Master election?.
10. For the nodes in Elasticsearch (for example, a total of 20), 10 of them choose one master, and the other 10 choose another master, what should I do? .....
11. How does the client select a specific node to execute the request when connecting to the cluster?
12. Detailed description-the process of indexing | documents in Elasticsearch.
13. Detailed description-the process of updating and deleting documents in Elasticsearch.
14. Detailed description-the process of Elasticsearch search. ...
15. In Elasticsearch, how to find the corresponding inverted index according to a word|
16. When Elasticsearch is deployed, what are the optimization methods for Linux settings?
17. Regarding GC, what should I pay attention to when using Elasticsearch? ...... 9
18.How does Elasticsearch achieve the aggregation of large amounts of data (on the order of hundreds of millions)?
19. In the case of concurrency, if Elasticsearch guarantees read and write-consistent?
20. How to monitor Elasticsearch cluster status?
21. Introduce the overall technical structure of your e-commerce search.
22. Introduction one; next your personalized search plan? ...
23. Do you know the dictionary tree?
24. How does spelling error correction work?
Memcached interview questions
1. What is Memcached and what does it do?
2. How to implement Memcached service distributed cluster?
3. What are the features and working principle of Memcached service?
4. Briefly describe the principle of Memcached memory management mechanism?
5. How does memcached work?
6. What is the biggest advantage of memcached?
7. Memcached and MySQL query.
8. Memcached and the server's local cache
9. What is the cache mechanism of memcached?
10.How does memcached implement the redundancy mechanism?
11. How does memcached handle fault tolerance?
12.How to import and export items in memcached in batches?
13. If the cached data expires between export and import, how do you deal with the data?
14. How does memcached do authentication?
15. What is the multithreading of memcached? How to use them?
16. What is the maximum key length that memcached can accept?
17. What is the maximum size of a single item that memcached can store?
18. Can memcached use memory more efficiently?
19. What is a binary protocol, should I pay attention to it?
20. How does the memory allocator of memcached work? Why does it not work?
malloc/free!? Why use slabs?
21. Is memcached atomic?
22. How to realize session shared storage in the cluster?
23. The difference between memcached and redis?
Redis interview questions
1. What is Redis
2. What is the data type of Redis?
3. What are the benefits of using Redis?
4. What are the advantages of Redis over Memcached?
5. What are the differences between Memcache and Redis?
6. Is Redis single-process single-threaded?
7.-What is the maximum storage capacity for a string type value?
8. What is the persistence mechanism of Redis? Their advantages and disadvantages?
9. Redis common performance problems and solutions:
10. What is the deletion strategy of redis expired keys?
11. Redis recycling strategy (elimination strategy) ?..
12.Why does edis need to put all the data in memory?
13.Do you understand the synchronization mechanism of Redis?
14. What are the benefits of Pipeline? Why use pipeline?
15. Have you used Redis cluster? What is the principle of cluster?
16.Under what circumstances will the Redis cluster solution cause the entire cluster to be unavailable?
17. What are the Java clients supported by Redis? Which is the official recommendation?
18.What are the advantages and disadvantages of Jedis and Redisson?
19.How to set password and verify password for Redis?
20. Tell me about the concept of Redis hash slots?
21. What is the master-slave replication model of Redis cluster?
22. Will there be write operation loss in Redis cluster? Why?
23.How is the replication between Redis clusters?
24. What is the maximum number of nodes in a Redis cluster?
25. How to choose a database for Redis cluster?
26. How to test the connectivity of Redis?
27. How to understand Redis transactions?
28. What are the commands related to Redis transactions?
29. How to set the expiration time and permanent validity of Redis key?
30. How does Redis optimize memory?
31. How does the Redis recycling process work?
32. What are the ways to reduce the memory usage of Redis?
33. What happens when Redis runs out of memory?
34. How many keys can a Redis instance store at most? List. Set. Sorted: How many elements can they store at most?
MySQL interview questions
1. What kinds of locks are there in MySQL?
2.What are the different tables in MySQL?
3. Briefly describe the difference between MyISAM and InnoDB in the MySQL database...:
4. The names of the four transaction isolation levels supported by InnoDB in MySQL, and the difference between them?
5. What is the difference between CHAR and VARCHAR?
6. What is the difference between primary key and candidate key?
7. What is myisamchk used for?
8. If a table has a column defined as TIMESTAMP, what will happen?
9. How do you see all the indexes defined for the table?
10. What does the% sum in the LIKE statement mean?
11. What is the column comparison operator?
12. What is the difference between BLOB and TEXT? ......
13. What is the difference between MySQL _fetch. array and MySQL fetch. object?
14. Where will the MylSAM form be stored and also provide its storage format?
15. How does MySQL optimize DISTINCT?
16.How to display the first 50 rows?
17. How many columns can be used to create an index?
18. What is the difference between NOW () and CURRENT. DATE ()?
19. What is a non-standard string type?
20. What is a general SQL function?
21. Does MySQL support transactions?
22. What field type is used to record currency in MySQL...
23. What are the MySQL tables related to permissions?
