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Java, Where To Start?
I'm a web developer who has design and programming experience. So, VB, ASP, PHP, Coldfusion, Perl, even C and C++ I have in my belt. I also use Dreamweaver and/or do a lot of my HTML/XHTML/JavaScript coding by hand. So, the DOM, DHTML, etc, all good to me and even OOP thinking and design I have when I code. And I even have MySQL and other databases, again, not an issue here. So, my weak point is — Java — I see so many jobs out there with J2EE, Hibernate, Eclipse, Netbeans. Beside the obvious, which is to learn Java the core language, I don't know where else to go from there. There is so much! What should I read? in what order? What software do I require? UML? Swing? I mean, what is the curriculum required for someone to say they are a solid Java developer? Even assuming I have to go through Java itself, what are the good books out there?
Isn't it better to specialise in a few of the varied languages and systems you have worked on, rather than trying to spread yourself thin?
There is truth in the saying 'jack of all trades - master of none'.
So, maybe concentrate on building up the other skills, rather than trying to 'bag' a new technology. I used to try to gain exposure to loads of different technologies but found that when you do so you do at the expense of the 'depth' of knowledge you have in any one.
Java is a good language to learn for the current marketplace.
The real problem thats putting people at risk of outsourcing is not the choice of language.
Its all about your skill as a programmer. If you're average, then there are plenty of average coders willing to work for less in India.
No, you've got to be better then average, great even, and that takes a lot of work.
A learning experience is one of those things that say, 'You know that thing you just did? Don't do that.' - D. Adams
Please, for the love of God, forget the frameworks. They come and go pretty quickly and each one is usually over-hyped to begin with.
Learn to be a great Java programmer. That means knowing the standard library in and out. Develop really good OO modeling skills. Learn what it means to write robust code. Understand and use exceptions effectively instead of littering blank catch blocks everywhere. All of these skills will serve you far better than knowing what arguments the RegistrarClassFactoryStubGeneratorJarBridge uses in its create() method. From there, as needs come up, you can experiment with higher-level abstractions. But please do NOT become one of those people that 'learns' that all database access should be handled through *insert-ridiculously-overcomplicated-framework-with-50-config-files-that-must-be-in-special-places.*
Aside: the reason Rails became so popular is because it managed to 'just work' without all of this inane configuration and magic files. The Java community is practically in love with complexity, since it is very enterprise-y.
The key is the libraries: that's where it goes from being merely another OO language to being able to do something useful. I'd start by getting a simple "hello world" program running, then thinking up a home project which allows you to start adding features and functions.
Most of the documentation I've seen is pretty poor - it gives argument lists and describes functionality in isolation, but misses out the higher level WHY you would want to use a function. Learning that is where the gold is.
politicians are like babies' nappies: they should both be changed regularly and for the same reasons
Java's an entire ecosystem unto itself these days. So there's no simple answer - you have to figure out what kind of apps you want to be involved in building, then that will inform your choice of Java based technologies. For the most part I do enterprise web site development, and that mostly on the server-side, so I'm a Java EE/Hibernate/Spring/Eclipse person. Plenty of professional experienced Java developers will never use any of those technologies!
Once you've figured out what kind of apps you want to be building, I'd suggest visiting the Sun Forums if you have any technical question and then poking around the Java.net site, theserverside.org, JavaRanch and the java usenet newsgroups to get a better feel for what's out there and how it's rated by developers. Feel free to drop me an email if you have any questions that you want to ask offline.
Ignore the naysayers - for the most part they don't know what they're talking about. Sure you should have other languages under your belt, sure there's offshore competition, but still, Java experts are in demand and they will be for a long time yet.
--- These are not words: wierd, genious, rediculous
I don't understand your logic. Java is fast, powerful, portable, and clean. Just because a lot of other people have realized how great it is doesn't mean that one shouldn't learn it. Java seems to be one of those things that people don't want to use just because it's "too" good.
while(1) attack(People.Sandy);
It's a difficult industry to get into as you're probably aware. Recruiting for Java posts is a minefield - it's full of people who should be stacking shelves in a supermarket.
I don't think you can go far wrong if you get as much experience in core Java as possible. The same goes for J2EE; if you understand what it is and know the trials and tribulations of building a web-app from scratch, you're on the right track. Then, and only then, should you move onto working with frameworks; so build applications both stand-alone and web, and do the boring stuff yourself (i.e., write your own web.xml.)
Spring and Hibernate are funny ones. Spring's just an IoC framework. Until you're proficient in OO design, you probably shouldn't worry about it. Oh, and learn what IoC is first. Don't just think 'spring' and say you know it. Very few people know why they chose spring as a framework (there are plenty of IoC containers out there).
Hibernate (an ORM solution) is a dark art. Get the basics done first. Write JDBC DAOs yourself and learn why you'd need ORM before you dive into it.
Basically, learn the core concepts.
ilovegeorgebush
O'Reillys "Head First Java" is IMHO the best technical resource / learning tool I've ever used; it's honestly fun to read. You can read it online for 30 days free using the Safari service.
A favorite excerpt of mine (on how to remember the single-inheritance, multiple-interface concept):
Roses are red,
Violets are blue,
Extend only one,
But implement two!"
Honestly, all of these acronyms you can list, and yet you don't have the initiative to learn another language without posting silly questions like this?
It's not about "learning a new language". Learning Java is trivial. The problem is the hundreds of bloated, redundant, incompatible "frameworks" and "libraries" that exist for Java. Which one to learn is a valid question (albeit, it doesn't have a good answer).
Seriously, is there some shortage on Java dicumentation out there or something? Granted, I don't know the language as I never had a need for it, but I can't trip over without falling into a pile of Java tutorials.
That is precisely the point of the question. You could quite easily spend 6 months solidly reading the stuff out there, so what OP is looking for is a recommendation or two to save him spending months finding the stuff that's worth reading in the piles of dross. I'm hoping there are some good answers, because I to would quite like to get a handle on the more enterprisey side of Java.
I never really liked NetBeans, I tried it with ver 5 and decided to stick with IntelliJ and Eclipse.
This is one of the examples that us Java foreigners want to learn. Here are some Java buzzwords that you see in jobs asking for devs:
Netbeans
J2EE
Eclipse
Jakarta
Struts
MVC (which isn't a java-only concept, but then again, newbies don't know)
Websphere
I really wish there would be an "intro to java technologies" book that explained newbies like me, with diagrams and colored figures what the heck is each buzzword and what it means, but I don't just mean a dictionary paragraph.
See, anyone could spend a couple of days googling each buzzword, but then there's the problem that one could learn TOO MUCH and get TOO DEEP trying to undersand ONE OF MANY things in java. And then you can find out that what you learned won't get you anywhere because suddenly the technology you learned became obsolete.
Around 8 years ago, I tried to learn java and JSP, and then found out that everyone switched to J2EE. Then I tried to learn J2EE and completely got lost. Then I tried to look at some J2EE courses sponsored by IBM but they costed at least $600. Then I said "fuck it, I'll stick to PHP. I can install an Apache webserver in one click on my Windows compy and I'll learn PHP on my own - for free". Try that with Java. See, the problem isn't the language itself, but the bunch of stuff built on Java, the frameworks built on java, AND the popular apps built upon some of the java frameworks, which is actually what the companies expect you to know.
What we need is a broadth-first approach of learning, starting with the language (one chapter for the java basics and examples should be enough). I mean explaining only the basics of each, comparing different technologies, telling you where they fit in a web app, and which ones are recommended or not, and why.
As a Java developer for nigh on ten years now, and someone who painfully learned how to program database connections by hand, then use orms like Hibernate, I might caution against Struts (though the rest of your order-of-learning is excellent). Struts was definitely in my path of learning, but I am not sure what it offers these days that isn't done more comprehensively - and to my mind, more cleanly - with Spring.
Of course, there are a lot of legacy systems these days built on Struts - for good reason. So if you're looking to work on older code, it's not a bad thing. But if you're planning a career with stuff that is from scratch, I think that Spring forces one to code in a better manner than nearly any other framework out there.
It may be, of course, that I'm just in love with inversion of control - which I think is one of those things that, if you understand it, gives you a much better command of abstracted design.
One other thing I think is pretty cool is JavaBLACKbelt, which has a pretty good, community developed set of quizzes that are useful for gauging your own command of the language.
[Ego]out
Considering that Java has been (probably) the most used language for a while, you get a lot of crap. So, here's my "crap filter" list of what you should learn to really hop into the JVM ecosystem.
Books:
1. Effective Java, 2nd edition, by Josh Bloch
This covers most of the twists and turns of the basics that an experienced programmer would need. I wouldn't worry about getting a simpler book.
2. Java Concurrency in Practice
Understanding the JVM model of concurrency is important, and this is the only guide that had a pretty in-depth look into the subject. The Sun documentation absolutely sucks at covering concurrency.
APIs
1. Guice http://code.google.com/p/google-guice/
Dependency injection is the most recent thing that makes Java a very powerful language for building large appications. And Guice is by far the best implementation of DI. (Yeah, you could learn Spring, but I just don't care for it.)
2. Hibernate http://hibernate.org/
I hate Hibernate. But it basically set the standard for EJB3. If you know Hibernate, it's not a very hard road to learn all the other "enterprise" crap.
On the other hand, any substantial server-based solution probably uses a ORM solution like Hibernate.
3. Apache's Commons http://commons.apache.org/ and Jakarta http://jakarta.apache.org/
There is a ton of projects under the Jakarta umbrella these days. The first one to try out is the commons-lang libraries, which provide very easy to use toString. equals, and hashCode implementations that are 'good enough' 99% of the time. Why do you need those? Read Effective Java. :)
Interesting stuff:
1. Hadoop http://hadoop.apache.org/
Hadoop is an open-source implementation of Google's MapReduce idea.
2. Scala http://scala-lang.org/
Scala is my favorite "non-Java" JVM language by far. For me, the scala interpreter is how I learn APIs. In fact, most of my new code is in Scala, not Java.
3. Groovy, JRuby
Just some more used non-Java JVM languages. I've used JRuby a bit, but have moved on to Scala. It's still a significant project, however.
4. Web application frameworks: Wicket http://wicket.apache.org/ + Databinder http://databinder.net/
Wicket is the simplest page-based Web framework I've ever used. I just find it easier to navigate than Rails. If you really want an ORM-based solution, go for the Databinder extensions. Databinder will get you coding in a couple of minutes.
5. Restlet http://restlet.org/
We have several different clusters, and a bunch of machines that need to transfer data around. I learned how to set up a restlet server that was integrated with Guice in a couple of hours, and now, have a very easy means to script together many different servers.