In the technical interview, the interviewer’s hard strength will be tested, mainly from two perspectives:
- Breadth: How comprehensive the knowledge is
- Depth: Depth of mastery
Width determines to some extent whether you get into a company, depth determines the level of your offer. For BAT, and even better companies, sometimes depth can be the difference between getting into the company or not.
In the past few months, after deep thinking and summary, I have finally sorted out the following points in detail, as long as you read them carefully and keep them in mind, but to master them, you have to use them in practice.
The specific knowledge points are as follows:
- Java foundation 32 questions and answer analysis
- JVM and tuning 20 questions and answers
- Multithreading & concurrent programming 22 questions and answer analysis
- Spring source code must ask 13 questions and answer analysis
- Mybatis source must ask 12 questions and answer analysis
- Spring Boot 14
- MySQL optimize 10 questions and answer parsing
- Redis 11
- Spring Cloud microservices 10 questions and answers
- Nginx interview questions and answer analysis
- MQ interview questions and answer analysis
- Data structure and algorithm interview questions and answer analysis
- Linux interview questions and answer analysis
- .
Of course, there are matching video tutorials, need to document and video can be forwarded to the end of the public account to obtain
First, Java basics
- What are the features of the Java language
- The difference between object-oriented and procedural
- The size of the eight basic data types, and their encapsulation classes
- Naming rules for identifiers.
- The role of the instanceof keyword
- Java automatic packing and unpacking
- The difference between overloading and overwriting
- Equals ==
- The role of Hashcode
- What is the difference between String, String StringBuffer, and StringBuilder?
- Difference between ArrayList and linkedList
- Difference between HashMap and HashTable
- Collection package structure, different from Collections
- Java four kinds of references, weak and weak virtual
- Common characteristics of generics
- How many ways can Java create objects?
- Is it possible that two objects that are not equal have the same Hashcode
- What is the difference between a deep copy and a shallow copy?
- What are the uses of final?
- What are the uses of static?
- 3*0.1==0.3 what is the return value
- Is there any difference between a=a+b and a+=b?
- Try catch finally, try has a return, is finally executed?
- Excption with Error package structure
- OOM you have encountered what situation, SOF you have encountered what situation
- Describes the basic concepts of threads, programs, and processes. And what is the relationship between them?
- What are the basic states of a thread?
- What if some fields in Java serialization do not want to be serialized?
- In Java IO streams
- Java IO vs. NIO
- How Java reflection works
- What is the difference between a List, a Set, and a Map?
Java basic answer parsing
Second, the JVM
JVM memory brain map
- Briefly describe the MEMORY model of the JVM
- The difference between heap and stack
- When will FullGC trigger
- What is a Java Virtual machine? Why is Java called a “platform independent programming language”?
- Java memory structure
- Object allocation rules
- Describe how the JVM loads class files.
- Java object creation process
- Class life cycle
- Describe the Java object structure
- How do I determine if an object can be reclaimed?
- Does garbage collection occur in JVM permanent generations?
- Garbage collection algorithm
- What are the tuning commands?
- Tuning tool
- When does the Minor and Full GC occur?
- You know what JVM performance tuning is
- .
JVM answer parsing
Multithreading & concurrency
- There are several ways to implement multithreading in Java
- How do I stop a running thread
- What’s the difference between notify() and notifyAll()?
- What is the difference between sleep() and wait()?
- What is volatile? Can order be guaranteed?
- What is the difference between the start() and run() methods in Thread?
- Why are wait, notify, and notifyAll not in thread?
- Why are wait and notify called in synchronous blocks?
- What is the difference between the interrupted and isInterruptedd methods in Java?
- What is the difference between Synchronized and ReentrantLock in Java?
- There are three threads T1,T2,T3, how to ensure sequential execution?
- What is the difference between SynchronizedMap and ConcurrentHashMap?
- What is thread safety
- What does the yield method in the Thread class do?
- What is the difference between submit() and execute() methods in Java thread pools?
- Talk about what you know about synchronized
- Do you use synchronized in your project? There are three main ways to use synchronized:
- What is thread safety? Is Vector a thread-safe class?
- What does the volatile keyword do?
- What are common thread pools?
- Briefly explain your understanding of thread pools
- How do Java programs execute
Multithreading & Concurrent answer parsing
Spring source code
- Spring’s IOC and AOP mechanisms?
- What is the difference between the Autowired and Resource keywords in Spring?
- There are several ways of dependency injection. What are they?
- What is Spring
- Spring MVC process
- How does SpringMVC set up redirection and forwarding?
- What are the common annotations used by SpringMVC?
- Spring AOP understanding:
- Spring’s IOC understanding
- Explain the life cycle of Spring beans
- Explains the scope of several beans supported by Spring.
- Spring is based on XML injection beans in several ways:
- What design patterns are used in the Spring framework?
- .
Spring source code answer parsing
Five, MyBatis source code
- What is MyBatis
- Advantages and disadvantages of MyBatis
-
What is the difference between {} and ${}?
- What if the attribute name in the entity class is different from the field name in the table?
- How does Mybatis paginate? How does paging plug-ins work?
- How does Mybatis encapsulate SQL execution results as target objects and return them? What are the mappings?
- How do I perform batch inserts?
- Xml mapping file, in addition to the common select | insert | updae | delete tags, what other tags?
- How many ways can MyBatis implement one-to-one? How does it work?
- Does Mybatis support lazy loading? If so, how does it work?
- Mybatis level 1, level 2 cache
- .
MyBatis source code answer parsing
Six, Spring the Boot
- Why SpringBoot
- What are the core annotations for Spring Boot? Which notes are it mainly composed of?
- What are the ways to run Spring Boot?
- How do you understand the Starters in Spring Boot?
- How do I run some specific code when Spring Boot starts?
- Does Spring Boot need a separate container to run?
- What is a monitor in Spring Boot?
- How do I implement exception handling using Spring Boot?
- How do you understand the Starters in Spring Boot?
- What are the common springboot starter
- How can SpringBoot implement hot deployment?
- How to understand the Spring Boot configuration loading sequence?
- What are the core configuration files for Spring Boot? What’s the difference?
- How to integrate Spring Boot and ActiveMQ?
- .
Spring Boot
MySQL optimization
- What are the three paradigms of databases
- What are the database engines
- Differences between InnoDB and MyISAM
- Database transactions
- The index problem
- SQL optimization
- Explain the differences between DROP, DELETE, and TRUNCate
- What is a view
- What is inner join, left outer join, right outer join?
- What are the problems associated with concurrent transactions?
- What are the transaction isolation levels? What is the default isolation level for MySQL?
- How to optimize large tables?
- How to deal with the id primary key after the database is divided into tables?
- .
MySQL > alter database
Eight, Redis actual combat
- Redis persistence mechanism
- Cache avalanche, cache penetration, cache warming, cache update, cache degradation and other issues
- What is hot data and cold data
- What are the differences between Memcache and Redis?
- Why is single-threaded Redis so fast
- Redis data types and usage scenarios for each data type
- Redis expiration strategy and memory flushing mechanism
- Why is Redis single threaded
- Redis Common performance issues and solutions?
- Why are Redis operations atomic and how are they guaranteed to be atomic?
- Redis transactions
- .
Redis
Spring Cloud microservices
- What is a SpringCloud
- What are microservices
- What are the advantages of SpringCloud
- What is a service circuit breaker? What is service degradation?
- Eureka and ZooKeeper both provide service registration and discovery functions. What is the difference between the two?
- What is the difference between SpringBoot and SpringCloud?
- What does load balancing mean?
- What is Hystrix? How does it achieve fault tolerance?
- What is Hystrix circuit breaker? Do we need it?
- Talk about how RPC works
- .
Spring Cloud microservices
Ten, Nginx
- What is Nginx? What are its advantages and features?
- How does Nginx handle an HTTP request?
- List some features of Nginx
- List the differences between Nginx and Apache
- How can an undefined server name be used in Nginx to prevent requests from being processed?
- What are the Master and Worker processes on the Nginx server?
- Explain forward and reverse proxies in proxies
- Explain the use of Nginx
- .
Nginx = Nginx
Eleven, MQ
- Why use MQ
- MQ pros and cons
- What is the difference between Kafka, ActiveMQ, RabbitMQ and RocketMQ?
- How to ensure high availability?
- How to ensure the reliable transmission of messages? What if the message gets lost
- How do I ensure that messages are sequential
- How to solve message queue delay and expiration problem? What happens when the message queue is full? There are millions of messages waiting for hours. How do you fix them?
- Ideas for designing MQ
- .
MQ答案解析
These PDF xiaobian has been sorted out, need to receive friends trouble forward xiaobian this article, of course, there are collocation of video tutorials, need to document and video can be forwarded to the end of the public account to obtain
Xii. Data structure and algorithm
- There are {1,2,3,4,5,6,7,8,9} in the data, please randomly scramble the order and generate a new array (please implement in code).
- Write code to determine whether an integer is a power of 2.
- Suppose today is Sunday, March 1, 2015. Please calculate the day of the week 13 months and 6 days from now.
- There are two baskets A and B. Basket A contains eggs and basket B contains apples. Please use object-oriented thinking to exchange items in the two baskets (please use code).
- .
Algorithm problem analysis
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