In 2021, the competition in the Internet industry is becoming more and more severe, and the interview is becoming more and more difficult. I have been trying to compile a perfect set of interview guidelines for a long time, but IT is difficult to spare the time. I have prepared this set of 1000+ Channels Java interview manual for a whole month, and uploaded it to Github

This set of Internet Java engineer interview questions includes: MyBatis, ZK, Dubbo, EL, Redis, MySQL, Concurrent Programming, Java Interview, Spring, Microservices, Linux, Springboot, SpringCloud, MQ, Kafka Interview topics

Alibaba P8 spent a month developing the 32W word Java interview manual, which is available in PDF here for screenshots

Java Interview questions directory

​

MyBatis interview article

  1. What is Mybatis?
  2. Advantages of Mybaits:
  3. Disadvantages of myBatis framework:
  4. MyBatis framework applicable occasions:
  5. What are the differences between MyBatis and Hibernate?
  6. What’s the difference between # and $?
  7. What if the attribute name in the entity class is different from the field name in the table?
  8. Fuzzy query like words how to write?
  9. Usually, an Xml mapping file will write a Dao interface corresponding to it. This Dao interface works on tDa
  10. How does Mybatiz do pagination? How does paging plug-ins work?
  11. How does Mybati S encapsulate the sq execution result as the target object and what mappings are returned?
  12. How do I perform batch inserts?
  13. How do I get automatically generated (primary) key values? 14. How to pass multiple parameters in Mapper?
  14. What is Mybatis dynamic SQL? How does it work? What dynamic SQL is there?
  15. Select Xm1 mapping file, in addition to the common | insert lupdae | delete tags, there are
  16. Mybati Z is a semi-automatic dynamic ORM mapping tool. What’s the difference between it and automatic?
  17. – Pair – and – Pair – Associated query all
  18. MyBati s implementation – yes – how many ways? How does it work?
  19. MyBatiz implementation – There are several ways to implement MyBatiz. How does it work?
  20. Does Mybatiz support lazy loading and if so, how does it work?
  21. Mybati S level 1 and level 2 cache:
  22. What is the interface binding for MyBati S? What are the implementation methods?
  23. What are the requirements when using MyBatis mapper interface?
  24. How can YOU write a Mapper?
  25. Describe how Mybati s plug-in works and how to compile it

​

Zookeeper interview article

  1. ZooKeeper surface J 考 试?
  2. What does ZooKeeper offer?
  3. Zookeeper file system
  4. ZAB agreement?
  5. Four types of data nodes zNodes
  6. Zookeeper “Atcher mechanism – Data change notification
  7. The client registers the Watcher implementation
  8. The server handles the Watcher implementation
  9. The client calls back atcher
  10. ACL permission control mechanism
  11. Chroot feature
  12. Session management
  13. Server role
  14. Zookeeper Server running status
  15. Data synchronization
  16. How does ZooKeeper keep the order of transactions consistent?
  17. Why is there a Master in a distributed cluster? 16. What can I do if the ZK node is down?
  18. Zookeeper load balancing differs from NGINx load balancing
  19. What are the deployment modes of Zookeeper?
  20. How many machines are required for a cluster? What are the clustering rules?
  21. Does the cluster support dynamic addition of machines?
  22. Is Zookeeper’s wat ch listening notification on a node permanent? Why not yongfa?
  23. What are the Java clients of Zookeeper?
  24. What is Chubby and how does it compare to Zookeeper?
  25. Here are some common ZooKeeper commands.
  26. The relation and difference between ZAE and Faxos algorithm?
  27. Typical application scenarios of Zookeeper

​

Dubbo interview article

  1. Why Dubbo?
  2. What are the layers of Dubbo’s overall architectural design?
  3. What communication framework is used by default, and what other options are there?
  4. Is the service invocation blocking?
  5. What registry is commonly used? Is there any other option?
  6. What serialization framework is used by default, and what else do you know?
  7. What is the principle that service providers can achieve invalidation? How does the launch of the service not affect the old version?
  8. How to solve the problem of long service invocation chains? 10. What are the core configurations?
  9. What protocol does Dubbo recommend?
  10. Can a service be directly connected to multiple registrations of the same service?
  11. Draw a flowchart for service registration and discovery?
  12. How many options are there for Dubbo cluster fault tolerance?
  13. Dubb. Service degraded, failed to retry what to do?
  14. Dubb. What are the problems encountered in the process of use?
  15. How does Dubbo Monitor work?
  16. What design patterns does Dubbo use?
  17. How is the Dubbo configuration file loaded into Spring?
  18. What is the difference between Dubbo SPI and Java SPI?
  19. Dubb. Are distributed transactions supported?
  20. Can Dubbo cache the results?
  21. How can the service be compatible with the old version?
  22. What packages must Dubbo rely on?
  23. What does the Dubbo Telnet command do?
  24. Is Dubbo support service degraded?
  25. How does Dubbo stop gracefully?
  26. The difference between a Dubbo and a Dubbox?
  27. What’s the difference between Dubbo and Spring Cloud? What other distributed frameworks do you know about?

​

Redis interview article

  1. What is Redis?
  2. Redis data type?
  3. What are the benefits of using Redis?
  4. What are Rediz’s advantages over Memcached?
  5. What are the differences between Memcache and Redi S?
  6. Is Redis single-process or single-threaded?
  7. What is the maximum capacity that a string value can store?
  8. What is the persistence mechanism for Redi S? What are their strengths and weaknesses?
  9. Redi s common performance issues and solutions: redis expiration key deletion policy?
  10. Redis’ recycling strategy (Obsolescence strategy >?
  11. Why does EDIz need to put all data in memory? 13. Redi Z synchronization mechanism?
  12. What are the benefits of Fipeline and why pipeline?
  13. Have you used Redi Z clustering and how does clustering work?
  14. Redi S Cluster solution When can the entire cluster become unavailable?
  15. What are the Java clients supported by Redi S? Which is the official recommendation?
  16. What are the pros and cons of Jedi Z versus Redi Sson? 19. Redi S how to set and verify the password? 20, Redi s hash slot
  17. What is the master-slave replication model for a Redi Z cluster? 22, Redi = will some operations be lost in the cluster? Why is that? 23. How are Redi Z clusters replicated between clusters?
  18. What is the maximum number of Rediz cluster nodes? How to select database for Redi Z cluster? 26, How to test the connectivity of Redis? How to understand Rediz transaction?
  19. What are the commands related to Redi Z transactions?
  20. How to set the expiration sample and permanent validity of Redis key respectively?
  21. How does Redi S optimize memory?
  22. How does the Redis recycle process work?
  23. What are some ways to reduce memory usage in Redi S?
  24. What happens when Redi S runs out of memory?
  25. How many keys can a Redi Z instance hold? List, set, Sorted set they can save at most
  26. There are 2000W data in MySQL. Redi =, there are only 20W data in redi =, how to ensure that data in REDis is hot
  27. The best scenario for Redi S?
  28. There are 100 million keys in Rediz and 10W of them start with a fixed known prefix
  29. If a large number of keys need to be set to expire at the same time, what should I pay attention to?
  30. Have you used Rediz to do asynchronous queues? Key, where there are 10W kes. fixed known prefixes
  31. Used Redi S distributed lock master is needle art still thing to learn”

​

MySQL interview article

  1. What types of locks are available in MySQL?
  2. What are the different tables in MySQL?
  3. Introduce the difference between My SAM and InnoDB days in MySQI database
  4. InnoDB supports four transaction isolation levels in MysQL, and what are the differences between them?
  5. The difference between CHAR and VARCHAR?
  6. What’s the difference between primary keys and candidate keys?
  7. What is Myisamchk used for?
  8. What happens if a table has a column defined as TIMESTAMP?
  9. How do you see all the indexes defined for the table?
  10. What do you mean by % and _ in the LTRE declaration?
  11. What is the column comparison operator?
  12. What’s the difference between BLDE and TEXT?
  13. What is the difference between MysQL_fetch_array and MySQL_fetch_object?
  14. Where will the MyISAM table be stored and its storage format provided?
  15. How does MySQI optimize DISTIHCT?
  16. How do I display the first 50 lines?
  17. How many columns can be used to create an index?
  18. What is the difference between Now () and CURRERT_DATE ()?
  19. What is a nonstandard string type?
  20. What is the general sQI function?
  21. Does MySQL support transactions?
  22. What is the best field type in MysQL to record currency
  23. MySQL > select * from ‘MySQL’ where ‘privileges’ are stored.
  24. What can be the string type of a column?
  25. MySQI teaching data library for release system storage, a day more than 50,000 increase in the estimated operation and maintenance of three years?
  26. Optimization strategies for locking
  27. The underlying implementation principles and optimizations of indexes
  28. When is an index set but not available
  29. How to optimize MysQL in practice
  30. Methods to optimize the database
  31. In MySQL, the difference between index, primary key, unique index and joint index affects the performance of the database
  32. What are transactions in a database?
  33. What is the cause of SQL injection vulnerability? How to prevent it?
  34. Select the appropriate data type for the fields in the table
  35. Storage period
  36. Indexes are an important concept for relational databases. Please answer some questions about indexes:
  37. Explain the difference between external join, inner join and self-join in MySQL
  38. Overview of the transaction rollback mechanism in Myql
  39. What are the parts of SQL and what are the operating implications of each part?
  40. What are integrity constraints?
  41. What is a lock?
  42. What is a view cursor?
  43. What is a stored procedure? With what?
  44. How to understand the three paradigms popularly?
  45. What is a basic table? What is a view?
  46. I Describe the advantages of views?
  47. What does hui.l mean
  48. Differences between primary keys, foreign keys, and indexes
  49. What can you use to ensure that fields in a table only accept values in a specific range?
  50. What are the methods for SQL statement optimization? “Choose a few.”

​

Java concurrent programming

  1. Three elements of concurrent programming?
  2. What are the ways to achieve visibility?
  3. The value of multithreading?
  4. What are the ways to create a thread?
  5. How do you compare the three ways to create threads?
  6. Thread state flow diagram
  7. Jave threads have five basic states
  8. What is a thread pool? What are the ways to create it?
  9. Four types of thread pool creation
  10. What are the advantages of thread pools?
  11. What are the common concurrency classes?
  12. Difference between Cycli cB arr I er and CountDownLatch
  13. What does Synchr oni Zed do?
  14. The role of the volatile keyword
  15. What is the CAS
  16. The problem of the CAS
  17. What is the Future?
  18. What is the AQS
  19. A0S supports two synchronization modes:
  20. What is Re adYri teLock
  21. What is FutuwreTask
  22. The difference between Synchr oni ze d and Reentr antLoc
  23. What are optimistic locks and pessimistic locks
  24. How does thread B know that thread A has changed the variable
  25. Syn. CHR oni Zed, Volatile, CAS comparison
  26. What is the difference between the Sleep method and the WAI T method?
  27. What is ThreadLoca1? What’s the use?
  28. Why the WAI T 0 method and noti FY 0/ Noti fyAll(
  29. Method to be called in a synchronized block
  30. What are the methods of multithreaded synchronization?
  31. Scheduling policy for threads
  32. What is the Concurr entHashMap concurrency
  33. How do I find which thread is using the most CPU in Linux
  34. Java deadlocks and how to avoid them?
  35. Cause of deadlock
  36. How do I wake up a blocked thread
  37. How can immutable objects help multithreading
  38. What is multithreaded context switching
  39. What happens if the thread pool queue is full when you submit a task
  40. What is the thread scheduling algorithm used in Java
  41. What are Thread Sche duler and Time Slicing?
  42. What is a spin lock
  43. What is the Lock Face in the Java Concurr ency API
  44. Thread safety in singleton mode
  45. What does Semaphore do
  46. Executors?
  47. The constructor of the thread class, the static block, is used by which thread
  48. Which is a better choice, synchronous method or synchronous block?
  49. What exceptions can be caused by too many Java threads?

​

​

Spring interview article

  1. What is spring?
  2. What are the benefits of using the Spring framework?
  3. What modules does Spri NE consist of?
  4. Core container (application context) module.
  5. BeanFactory a BeanFactory implementation example.
  6. XMLBeanF actory
  7. Explain AOP modules
  8. Explain the JBC abstraction and DAD modules.
  9. Explains the object/relational mapping integration module.
  10. Explain the WEB module.
  11. Sprinr configuration file
  12. What is the Spring IOC container?
  13. What are the advantages of IOC?
  14. What’s the usual implementation of Appli cati onContext?
  15. What is the difference between Bean Factory and Application Contexts?
  16. What does an APPLICATION of Spr ine look like? Dependency injection
  17. What is Dependency injection in Sprine?
  18. What are the different types of I0C (dependency injection) approaches?
  19. Which dependency injection method do you recommend, constructor injection or Setter injection?
  20. What are Spring beans?
  21. What does a Spring Bean definition contain?
  22. How do I supply Spring containers with 2-byte metadata?
  23. How do you define the scope of a class?
  24. Explains the scope of several beans supported by Spr ing.
  25. Are singleton beans in the Spring framework thread-safe?
  26. Explains the life cycle of beans in the Spr ing framework.
  27. What are the important bean lifecycle methods? Can you reload them?
  28. What is the internal bean of Spri NE?
  29. How do I inject a Java collection in Spring?
  30. What is bean assembly?
  31. What is bean autowiring?
  32. Explain the different ways of automatic assembly.
  33. What are the limitations of autowiring?
  34. Can you inject a NU11 and an empty string into Spring?
  35. What is the Jav based Sprine main solution configuration? Give some examples of annotations.
  36. What is annotation-based container configuration?
  37. How to start annotation assembly?
  38. @ Required annotations
  39. The @autowired annotation
  40. @ the Qualifier annotations
  41. How can I use JDBC more effectively in the Spr ING framework?
  42. JdbeTemplate
  43. Spring’s support for DA0
  44. How to access Hi Bernate using Spr ing?
  45. Spring supports 0RM
  46. How to combine sping with Hibernate via Hi bernateDaoSuppor t?
  47. The type of transaction management supported by Spring
  48. What are the advantages of transaction management in the Spring framework?
  49. Which transaction management style do you prefer?
  50. Explain the AOP
  51. The Aspect Aspect
  52. What is the difference between concerns and crosscutting concerns in Spring AOP?
  53. The join
  54. notice
  55. Point of tangency
  56. What is introduction?
  57. What is the target object?
  58. What is agency?
  59. How many different types of automatic agents are there?
  60. What is weaving in. What are the differences in weaving applications?
  61. Explains the XML – based Schem approach to the implementation of facets.
  62. Explains annotation-based aspect implementations
  63. What is the MYC framework for Spr ine?
  64. DispatcherSerlet
  65. WebApplicati onContext
  66. What is the Spring MVC framework controller?

​

​

Kafka interview article

  1. How do I get a list of topi C topics
  2. What is the producer and consumer command line?
  3. Is consumer push or pull?
  4. Talk about how Kafk maintains consumption status tracking
  5. Talk about master-slave synchronization
  6. Why do you need a messaging system? Doesn’t mysQ1 fit the bill?
  7. What does Zookeeper do for Kafka?
  8. What are the three transaction definitions for data transfer?
  9. What are the two conditions for Kafka to determine if a node is still alive?
  10. There are three key differences between Kafka and traditional server messaging systems
  11. Talk about the three mechanisms of KAFks AC
  12. How to solve the problem of consumer failure and live lock?
  13. How to control the location of consumption
  14. How can messages be consumed sequentially in a distributed (not stand-alone) Kafka scenario?
  15. What is the high availability mechanism of Kafks?
  16. How does Kafka reduce data loss
  17. How does Kafka not consume duplicate data? For example, deduction, we can’t double deduction.

​

Micro service interview

  1. What do you know about microservices?
  2. What are the advantages of microservices architecture?
  3. What are the features of microservices?
  4. What are the best practices for designing microservices?
  5. How does the microservices architecture work?
  6. What are the advantages and disadvantages of microservices architecture?
  7. What are the differences between monolithic, SOA and microservice architectures?
  8. What challenges do you face when using the microservices architecture?
  9. What are the key differences between S0A and microservices architectures?
  10. What are the features of microservices?
  11. What is Domain-driven design?
  12. Why domain Driven Design (DDD)?
  13. What is the ubiquitous language?
  14. What is cohesion?
  15. What is coupling?
  16. What is REST 1 RESTfu and what is it used for?
  17. What do you know about Spring Boot?
  18. What is a Spring-booted executor?
  19. What is Spring Cloud?
  20. What problems does Spring Cloud solve?
  21. What is the use of the W ebMvcTest annotation in a Spring MVC application?
  22. Can you give me some key points about breaks and microservices?
  23. What are the different types of microservice testing?
  24. What do you know about the Distributed Tr ansacti on?
  25. What is I Dempotence and where is it used?
  26. What is bounded context?
  27. What is two-factor authentication?
  28. What are the credential types for two-factor authentication?
  29. What is a customer certificate?
  30. What is the use of FACT in the microservices architecture?
  31. What is a 0 auth?
  32. What is Conway’s law?
  33. What do you know about contract testing?
  34. What is end-to-end microservice testing?
  35. What is the use of Container in microservices?
  36. What is DRY in microservices architecture?
  37. What are consumer-driven contracts (CDC)?
  38. What is the role of Web, REST ful apis in microservices?
  39. What do you know about semantic monitoring in microservices architecture?
  40. How do we do cross-functional testing?
  41. How do we eliminate determinism from testing?
  42. What’s the difference between a Mock or a Stub?
  43. How much do you know about MikeCohn’s test pyramid?
  44. What is the purpose of Docker?
  45. What is canary Release?
  46. What is Continuous integration (CI)?
  47. What is continuous monitoring?
  48. What is the role of the architect in the microservices architecture?
  49. Can we create state machines with microservices?
  50. What is reactive scaling in microservices?

​

Elasticsearch (24 tracks) Memcached (23 tracks) SpringBoot (22 tracks) SpringCloud (8 tracks) Linux (45 tracks) MQ (12 tracks)

The following is a list of all the interview questions in Java. If you are interested in this 1000-lesson Java interview book, you can click here to get a screenshot

​