Finally, some people have sorted out the 10 knowledge points that senior programmers must know, like the initiation

Posted May 26, 20206 min read

How many years have I worked, and I still write simple codes such as if/for in traditional companies? Then you really have to be eliminated by society. How many differences are you from junior engineers after working for many years? So what knowledge points do you need to break through as an advanced Java siege lion?

  1. Java basic technology system, JVM memory allocation, garbage collection, class loading mechanism, performance optimization, reflection mechanism, multi-threading, network programming, common data structures and related algorithms.

  2. Have a clear understanding of object-oriented software development ideas, familiar with the commonly used design patterns.

  3. Master the current popular open source framework(spring/springmvc/ibatis), and have a certain understanding of its core ideas and implementation principles.

  4. Familiar with the development and design of Oracle, MySQL and other databases and the design and development of the cache system Redis or Memcached.

  5. Familiar with the underlying middleware, distributed technology(including caching, message system, hot deployment), message middleware:ActiveMQ, RabbitMQ, workflow middleware:JBPM.

  6. Proficient in shell programming, proficient in using common commands such as awk, sed, grep, strace, tcudump, gdb and so on.

  7. Have experience in designing and developing large-scale distributed, high concurrency, high load(large data volume) and high availability systems.

  8. Some understanding of configuration management and agile R & D mode(svn, git).

  9. Familiar with some common solutions and their principles:single sign-on, distributed cache, SOA, full-text search, message middleware, load balancing, connection pool, flow calculation, etc.

  10. Can roughly know the characteristics and business bottlenecks of mainstream technologies on the market.

Well, after reading it, I probably know what I am lacking, so I need to learn what to add! Being a programmer is really not easy!

Next, according to different aspects, they are displayed through knowledge system diagrams and documents. If you need this document and system architecture diagram, you can send the private message "data" after forwarding


JVM

No matter what level of Java practitioners, JVM is a hurdle that must be passed when advanced. Whether it is a job or an interview, the JVM is a required question. If you do not understand the JVM, the salary will be very disadvantageous(nearly 70%of interviewers hang on the JVM)

Introduces the JVM in detail about threads, memory models, JVM runtime memory, garbage collection and algorithms, four reference types in Java, GC generation collection algorithm VS partition collection algorithm, GC garbage collector , JAVA IO/The major knowledge points of NIO and JVM class loading mechanism.

basic concept:

The JVM is a hypothetical computer that can run Java code, including a set of bytecode instructions, a set of registers, a stack, a garbage collection, heap, and a storage method domain. The JVM runs on the operating system, and it has no direct interaction with the hardware.

Too many detailed knowledge points, too long to see the copy "Java core knowledge system"

JVM directory

Java Collection

Generally, our program needs to know how many objects are created based on the program runtime. But if the program is not running, at the stage of program development, we simply don't know how many objects are needed, or even its exact type. In order to meet these conventional programming needs, we require that any number of objects can be created at any time and any place, and what are these objects used to accommodate? We first thought of an array, but the array can only hold data of a uniform type, and its length is fixed, so what should we do? The collection came into being!

    1. Interface inheritance and implementation
    1. List
    1. Set
  • 4, Map

Java collection framework diagram

There are too many detailed knowledge points, and the copy is too long. "Java Core Knowledge System" There is a detailed decomposition version of the collection diagram to correspond to each knowledge point(see catalog)

Java multi-threaded concurrency

Let s take a look at the concurrent knowledge base system diagram:

  1. How is Java thread implemented/created?
  2. 4 kinds of thread pool?
  3. Thread life cycle(state)
  4. 4 ways to terminate the thread
  5. What is the difference between sleep and wait?
  6. What is the difference between start and run?
  7. Java background thread
  8. Java lock
  9. Thread basic method
  10. Thread context switching
  11. Synchronous lock and deadlock
  12. Thread pool principle
  13. Java blocking queue principle
  14. Usage of CyclicBarrier, CountDownLatch, Semaphore
  15. The role of the volatile keyword(variable visibility, prohibit reordering)
  16. How to share data between two threads?
  17. ThreadLocal role(thread local storage)
  18. The difference between synchronized and ReentrantLock
  19. ConcurrentHashMap concurrency
  20. Thread scheduling used in Java
  21. Process scheduling algorithm
  22. The concept and characteristics of threads

There are too many detailed knowledge points, and the copy is too long. "Java Core Knowledge System" There is a detailed decomposition version of the collection diagram to correspond to each knowledge point(see catalog)

Deep analysis of spring principle

Spring is used by more and more microservice practitioners because of its many advantages. By mastering Spring, you can become a leader in the field of rapid application development. However, if you know it, you need to know why. This article will help you understand the operating mechanism behind Spring from the perspective of Spring source code and core implementation principles.

Introduction directory

  1. Features of Spring
  2. Spring its core components
  3. Spring commonly used modules
  4. Spring main package
  5. Spring common notes
  6. Spring IOC principle
  7. Spring APO principle
  8. Spring MVC principle
  9. Spring Boot principle
  10. JPA principle
  11. Mybatis cache
  12. Tomcat architecture

There are too many detailed knowledge points, and the copy is too long. "Java Core Knowledge System" There is a detailed decomposition version of the collection diagram to correspond to each knowledge point(see catalog)

Forward this article and follow my private message reply [Information]How to get "Core Knowledge"

spring principle

Microservices

Microservices are the knowledge points you have to master in the Internet industry today, and also the hottest and most popular knowledge at present, let's take a look!

  1. Service Registration Discovery
  2. API Gateway
  3. Configuration Center
  4. Service tracking
  5. Service fuse
  6. API management

There are too many detailed knowledge points, and the copy is too long. "Java Core Knowledge System" There is a detailed decomposition version of the collection diagram to correspond to each knowledge point(see catalog)

Forward this article and follow my private message reply [Data]Consult how to get "Core Knowledge"

Because the copy is too long, I will not introduce it one by one here. The core knowledge summary knowledge points also include ** Netty and RPC, network, log, Zookeeper, Kafka, RabbitMQ, Hbase, MongoDB, Cassandra, 24 kinds Detailed knowledge of design patterns, load balancing, databases, consistency algorithms, Java algorithms, data structures, distributed caching, etc.

This knowledge system is suitable for all Java programmers to learn. The knowledge points in the above directories are explained and introduced in detail. Mastering all the contents of this knowledge point will have a qualitative improvement for you. It also summarizes many interview processes. Summary of the problems encountered and corresponding answers.

Forward this article and follow my private message reply [Information]How to get "Core Knowledge"

In addition, there are more projects, algorithms and source code content to share. If you need this information, you can also reply to the [Information]


Concerned about the public number:Java Architects Alliance, daily technical updates