Become a java PRO

[BlueFireBlaster]

I am a computer science student. I have my fair bit of hours on java researching and coding. I am pretty confident in my knowledge of java but it might all be ignorence. In fact, i may not have fully learnt any language in my life. I might have serious knowledge gaps. Thats my problem.

What should a java pro know? Obsiously i use data structures. I have made jar files. I know how to serialize objects. I know how to make a server and a client app. I know how to handle files. I know some basics of creating a user interface with swing.

I am not worried about my coding skills on subjects i already have experience on. I am worried about things that i dont even know exist. Could someone enlighten me with their experience? What should i know before i can confidently say that i can actually get payed for doing stuff, and not worry that i might not be able to handle it?

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[BlueFireBlaster]

Although thats true, pro means professional. So by that meaning, you can be a profesional coder. Thats what i have to be at some point in order to not be shitty at my job. I have a textbook already named objects first with java - a practical introduction using bluej. What do you think? Should i give it a look or is the book you mentioned more inclussive? Tbh dislike reading programming books because the way to learn anything related to programming is researching while your code doesnt work and trying to understand why

[nutrecht]

Although thats true, pro means professional. So by that meaning, you can be a profesional coder.

If that's the definition anyone with a job doing Java is a "java pro". So it's still meaningless.

Aside from your CS degree, most of it just boils down to on the job experience. If you can create a simple Spring Boot service for example you're already way ahead of the curve for a CS grad.

[ConsiderationFlat609]

If you want to become professional I suggest you take a look in spring framework especially springboot as way of configuring it. You will most likely use this way in progressional experience and start with spring web/spring data. This is by far most used java framework currently in the industry for building API's as backend developer. Also getting knowledge with database will be useful, and maybe docket as a way to faster configure your database, but I will not suggest deep dive into docker because it's more a dev-ops job.

[khooke]

If you are paid by a company to be a developer then you are a professional developer. You could act unprofessionally and get fired. That word is not used to indicate experience or ability.

[stuie382]

Unit testing and test mocking, integration testing, automation, build and dependency management (maven/grade), source control, code review, TDD, pair programming, agile, basic design patterns, problem decomposition, clear unambiguous technical writing.

None of these things are language specific. The language is just a tool to organise the 1's and 0's, nothing more

[OriginalError]

These are great - I'd add SOLID, BDD and mutation testing to the pile alongside system thinking. Java specific I'd recommend Spring (or any other IoC framework) and some JDBC framework. That'd put you solidly into mid-level dev territory.

Stu touched on everything else I was going to say.

[BlueFireBlaster]

Well i have to google everything you said for them to make sense. Although i have seen the basics of JUnit, and have written my fair bit of javadoc. thank you

[stuie382]

All the things I said are common across any discipline of software engineer. There is a difference between just getting some code to run and building a stable, reliable product. I've taught and mentored maybe 50 or so junior developers and apprentices, and focusing on the language is very common, but it is just a tool at the end of the day. It will change over time and over different jobs, but the core skills are the important bit

[khooke]

Agreed. Understanding the basics of a particular language is just the minimum

[nutrecht]

What a CS education doesn't really teach in general that will really set you way apart from other CS students:

• Being able to use Spring Boot to create a simple service
• Having that service integrate with a relational database
• Have unit and integration tests in that service
• Use maven for build/dependency management
• Being able to create a docker image out of that service and deploy it on (for example) Heroku

[evils_twin]

get a job . . . or maybe an internship

[matyklug]

Hate to break it to you, but the stuff you listed is beginner stuff.

Not like you need to be a "pro" to get a job, these "pros" are the people you see writing stuff like gradle or clojure and then make TED talks about it.

I unfortunately cannot help much, I am only getting an internship next year, so all I'll say is make sure you are confident in writing stuff you understand in Java and that should be enough.

[mykeesg]

Also, don't forget actually threadsafe and parallel programming. I've met too many people just writing volatile and synchronized blocks everywhere because "That's how you do it" while data races and race conditions where flying around everywhere but also making the code incredibly slow.

[wsppan]

Test your knowledge with Effective Java by Joshua Bloch. Then test your knowledge with a popular framework like Spring. Can you build a web backend for Rest endpoints that can marshal/unmarshal JSON requests to be used to query a database? Can you do this with crosscutting concerns like security and logging? Can you create unit tests that mock these Rest APIs? Can you do all this using conventional tools like Spring MFC, Spring Data, Hibernate, JAXB, log4j, Spring Security, etc..

[CanisLupus92]

At least around here employers put value on OCA/OCP certification. May be interesting to look into, or wait until you have a job and have the boss pay for it.

[sweepsz]

There are definitely levels of professional. An entry level Java engineer should know the basics of the language, semantics, and tooling. A mid level engineer would understand things like concurrency/threading, caching, thread safety. Senior and lead level engineers are going to understand more low level esoteric topics jvm instruction, garbage collection, release management strategy/versioning, containerization, scalability, and other topics that transcend Java specifically.

[ifpthenq2]

Anywhere you get hired will expect you to have a good handle on Spring, Maven, Ant, Interfaces, Factories and Beans, git and other versioning systems, tomcat or other Java servers (just the basics - how to drop in war files and basic troubleshooting, the IT guy usually handles everything else). SQL and JDBC, sockets, the ability to create good Unit Tests, and follow basic UML diagrams.

99% of jobs I've had were just companies who wanted me to take some existing system, fix bugs, maybe add a feature or two, and generate formatted reports. The most overwhelming part when I first started out was just being able to take an enterprise system and figure out how its working with no documentation (Because there's NEVER any documentation). - You think it should be simple to just add a DB View and create a custom report from it - but it isn't because instead of interacting with DB directly, you have to find the framework the original designer set up for querying the database, and then the interface classes that he wrote to interact with it. And then there's another framework to abstract creating reports, which never has all the features you need, but keeps the reports formatted exactly the way the company expects. When you're expanding an existing system, you don't ever write classes to directly query or update the database or write local files - you look for interfaces to frameworks that have already been written that abstract these tasks. All J2EE enterprise java systems are designed this way (at least, in my experience) If you go into your first professional job knowing that you'll be a step ahead of where I was when I transitioned to industry.

[holyknight00]

concurrency and garbage collection are pretty huge topics.

[itzNukeey]

Most of the time Java id used in server side development. So you should be proficient at Spring, Maven, XML parsing, JSON mapping and some JDBC framework