As a well-qualified Java developer, I have interviewed many people in the past few years. It is found that most interviewees, although they seem to work hard, their demonstrated ability level is not enough to pass the interview or get the expected salary.
In my opinion, there are two main reasons for this situation:
First, "knowing what is happening and not knowing why." I have worked on technology for several years and developed some business applications, but I haven't thought about the logic behind these technology choices. Therefore, it is difficult for me to locate their future growth potential, and I will not rest assured of entrusting them with tasks with a certain depth.
Second, knowledge is fragmented and unsystematic. In fact, when the interviewer is unable to completely and clearly describe the system he has developed or the related technology used, the interviewer will doubt whether he has the ability to solve complex problems and design complex systems.
Therefore, if you usually only know that you are working hard, or are too obsessed with certain implementation details, and have not looked up these technologies, then when preparing for the interview, it is necessary to sort out the Java knowledge system so that you can get a satisfactory offer. .
Here, I share a document "Java Core Skills Introductory" that has helped me a lot. I got it by accident. It came from a friend of mine. After reading it, he felt that it was written very well, very detailed and comprehensive. But a small part of the content has not been updated yet. I asked him where he came from. He only told me that it was copied from a boss who had worked for more than ten years.
The document covers knowledge:
Interview must ask: Java basics, high concurrency, multithreading, distributed, design patterns, Spring family bucket, Java, MyBatis, ZooKeeper, Dubbo, Elasticsearch, Memcached, MongoDB, Redis, MySQL, RabbitMQ, Kafka, Linux, Netty, Tomcat and other knowledge points are explained in detail and interview questions.
Since the entire document is relatively comprehensive and has a lot of content, if there is a need for friends who need to obtain information, there is a direct address at the end of the article.
In the document, based on the knowledge points and necessary abilities of the interviews of major companies, 485 Java interview questions are selected, not only giving typical answers and test site analysis, but also analyzing the core knowledge points of Java, so that you can understand the interview. The key capabilities of the inspection will help you achieve the goal of "knowing why" and systematization.
Java basics
- Java annotations
- Java reflection
- Java generics
- Java inner class
- Java replication
- Java serialization
- Java exception classification processing
Java basic mind map
JAVA basic corresponding detailed analysis document
JAVA basic corresponding detailed analysis document
Java multi-threaded concurrency
- JAVA Concurrent Knowledge Base
- JAVA thread implementation / creation method
- 4 thread pools
- Thread life cycle (state)
- 4 ways to terminate threads
- The difference between sleep and wait
- The difference between start and run
- JAVA background thread
- JAVA lock
- Basic thread method
- Thread context switch
- Synchronization and deadlock
- Principle of Thread Pool
- JAVA blocking queue principle
- Usage of CyclicBarrier, CountDownLatch, Semaphore
- The role of the volatile keyword (variable visibility, prohibit reordering)
- How to share data between two threads
- ThreadLocal function (thread local storage)
- The difference between synchronized and ReentrantLock
- ConcurrentHashMap concurrency
- Thread scheduling used in Java
- Process scheduling algorithm
- What is CAS (Compare and Exchange-Optimistic Locking Mechanism-Lock Spin)
- What is AQS (Abstract Queue Synchronizer)
Java multi-threaded concurrent mind map
Java multithreading concurrency knowledge points corresponding detailed analysis documents
Java multithreading concurrency knowledge points corresponding detailed analysis documents
JVM
- Thread
- JVM memory area
- JVM runtime memory
- Garbage collection and algorithms
- JAVA four reference types
- GC generational collection algorithm VS partition collection algorithm
- GC garbage collector
- JAVA IO / NIO
- JVM class loading mechanism
JVM brain map
JVM brain map corresponding detailed document analysis
JVM detailed document analysis
Spring principle
- Spring features
- Spring core components
- Spring common modules
- Spring main package
- Spring common annotations
- Spring third-party integration
- Spring IOC principle
- Spring AOP principle
- Spring MVC principle
- Spring Boot principle
- JPA principle
- Mybatis cache
- Tomcat architecture
Spring principle brain map
Spring principle corresponds to detailed analysis document
Spring principle corresponds to detailed analysis document
database
- Storage engine
- index
- Three paradigms of database
- The database is a transaction
- Stored procedure
- trigger
- Database concurrency strategy
- Database lock
- Distributed lock based on Redis
- Classification table
- Two-phase commit agreement
- Three-phase commit agreement
- Flexible transaction
- CAP
Detailed analysis documents corresponding to the database
Detailed analysis documents corresponding to the database
Data Structures and Algorithms
- data structure
- Encryption Algorithm
- JAVA algorithm
- Consensus algorithm
Data structure and algorithm brain map
Microservice
- Service registration discovery
- API gateway
- Configuration Center
- Event scheduling (kafka)
- Service tracking (starter-sleuth)
- Service Fuse (Hystrix)
- API management
Microservice brain map
Microservices for parsing documents
Microservices for parsing documents
Netty 与 RPC
- Netty principle
- Netty high performance
- Netty RPC implementation
- RMI implementation
- Protoclol Buffer
- Thrift
Netty and RPC mind map
Detailed analysis documents corresponding to Netty and RPC
Detailed analysis documents corresponding to Netty and RPC
The internet
- 7-tier network architecture
- TCP/IP principle
- TCP three-way handshake/four waved hands
- HTTP principle
- CDN principle
Zookeeper
- Zookeeper concept
- Zookeeper role
- How Zookeeper Works (Atomic Broadcast)
- Znode has four types of directory nodes
Kafka
- Kafka concepts
- Kafka data storage design
- Producer design
- Consumer design
RabbitMQ
- concept
- RabbitMQ architecture
- Exchange type
Hbase
- concept
- Columnar storage
- Hbase core concepts
- Hbase core architecture
- Hbase's writing logic
- HBase vs Cassandra
Cassandra
- concept
- Data model
- Cassandra consistent hash and virtual node
- Gossip protocol
- Data replication
- Data write request and coordinator
- Data read request and background repair
- Data storage (CommitLog, MemTable, SSTable)
- Secondary index (a RowKey is generated for the summary of the value to be indexed)
- Data read and write
Load balancing
- Layer 4 load balancing vs. Layer 7 load balancing
- Load balancing algorithm/strategy
- LVS
- Keepalive
- Nginx reverse proxy load balancing
- HAProxy
HaDoop
- concept
- HDFS
- MapReduce
- The life cycle of Hadoop MapReduce jobs
Spark
- concept
- Core architecture
- Core components
- SPARK programming model
- SPARK calculation model
- SPARK operation process
- SPARK RDD process
- SPARK RDD
Obtaining method: Pen friends who need this Java core knowledge study notes [see the figure below to add a small assistant] to get it
