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Someone privately messaged me and said that in addition to the 20% to be mastered, what kind of knowledge should be mastered to be able to do well. Let's talk about what I have come into contact with (used) and things.
Java is famous for its rich ecology of distributed applications, and it cannot escape the choice of CAP in distributed systems. Get to know some distributed consensus protocols paxos, raft, etc. early. Learn the principles and usage scenarios of zookeeper (metadata, distributed locks, leaderEletion... etc)
The RPC framework plays an important role in the SOA architecture, and it is beneficial to explore it well. I recommend Alibaba's dubbo framework here, and also network libraries such as netty and mina.
Offline/real-time computing frameworks such as Hadoop series Storm Spark
ElasticSearch\SolrCloud distributed search ELK log related things are more sensitive to these, of course, there are many uses of ES in more scenarios
Message queue kafka\MetaQ RabbitMQ Well, the author of ZeroMQ (not exactly MQ) chose euthanasia yesterday, may there be no pain in heaven
Then there are the various basics, programming languages, networking aspects, databases, data structures and algorithms. Don't feel that you are proficient in any item, and dare to say that there are several Zhihu who are proficient.
= = There are too many things, the above are the common things in the industry at present. Different problems will be encountered in different jobs, and more tools and open source frameworks are needed to solve various problems. Then there will be more and more things, and then I don't know what I will write. Done first, please private message me for details
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Some of the main libraries include:
commons-* (apache common library, including common IO, collection, network, log, etc., it seems that there are at least 40+commons libraries, but only those are commonly used, see Apache Commons for details)
The guava library is googled. I like to use this tool library the most~, but some things are only available in the commons library above, such as LRUmap. But google has cache hahaha
fastjson, used for manipulating json
Common frameworks:
SpringMVC, Mybatis Spring, the most commonly used web development, of course, also use RPC framework, you can refer to Thrift dubbo gRPC, etc.
tool
git maven
These are the ones that are commonly used, not to mention those that are not commonly used. Look at the content of your work, of course, you can't find a job if you know what you know, the key is your ability to learn. There are new technologies that can be learned best in the shortest time. Maybe these things will be eliminated this year, maybe~
Reprinted from: https://www.zhihu.com/question/38880482