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I learnt swing basics and event handling basics from head first java...
Then i read a few tutorials on swing app development using netbeans...
and i loved it as i don't have to care about layouts and stuff...
But i read in one of the forums, that i should learn swings properly rather than using netbeans directly...
This confused me a bit....
Please suggest the best way to master development of swing apps....
thanks in advance
Well, I see I'm going to run counter to the majority here ;-)
Hand coding GUIs is a pain in the ass. Anything that makes that task easier is a good thing in my book. When you're just starting, having a generated GUI lets you get up and running faster.
GUI builders handle the really repetitive work and prevent you from doing the most common dumb things. The downside is that same approach will also prevent you from doing the really clever things. Eventually, you will encounter something that you cannot do through the GUI builder and you will need to poke into the code. So, you can't treat code generators like black boxes where you don't need to know what magic happens inside. At minimum, you need white boxes. Let the GUI builder do its magic, but understand that magic and its limitations.
Practice by generating a very simple GUI. Walk through the code and understand what it does. Make a change through the builder and see how the generated code changes. Try changing the code yourself to confirm you understanding is correct. *
If you don't understand something, hit the JavaDocs, the Swing Trail, or browse through the Java2S Swing Tutorials.
If you're still stuck try the kind folks at Java Ranch, or here on StackOverflow.
* Netbeans puts the generated code in guarded blocks and will not let you edit them directly. However, you can open the file in another editor to test a change. Also, you can do quite a lot to influence the code generation using the code tab in the properties window.
It depends on what you see as your goal.
There is no "perfect" approach to get comfortable using Java and swing, it always depends on what you want the outcome to be like.
Most enterprises depend on stability and speed, programmers need to write code fast and stable. If you write complex interfaces by hand it gets ugly when it comes to speed and precision at the same time. You can never write better code in terms of "it is working" then the netbeans gui builder can. Also, no one will probably have a look at your code once the application is up and running.
If you want to get to know swing only for the purpose of knowing it with no deeper intention what so ever, I'd recommend learning it by heart without netbeans as you'll probably familiarize yourself with most of it's functionality quicker then the other way around.
On one hand, if I want to learn something, I want to learn it from scratch, so I would probably go with writing swing-code myself and in the end using netbeans to generate it when I am fully able to comprehend what is generated.
On the other hand, if I need to write applications quick and am not paid to go into any details, I'd simply use netbeans.
I think you have answered yourself... you want to master development of swing apps...
everything that you do by autogenerating without knowing why or how is not mastering in my opinion ;)
If you want to be master, then you should at least know how to do it with your bare hands. Moreover, it will also help you if you will use other gui toolkits (main principles of gui toolkits are more or less the same, imho).
I've decided to get some experience working on some project this summer.
Due to local demand on market I would prefer to learn Java (Standard and Enterprise Editions).
But I can't even to conjecture what kind of project to do. Recently I had some ideas about C. With C I could to contribute to huge Linux projects. I don't mean that my work will be surely commited. I could get the code and practice with it. But C it's not right thing to get good job in my area. In case of JavaSE there is a chance to develop some desktop applications. But thinking about JavaEE I get stuck. I'll be very thankful for answers.
CodingBat.com will give you good core Java practice.
Project Euler is still the best for all around practice. You can use whatever language you'd like to solve the problems there.
For actual projects, I almost always start on something easy like a Twitter client. It gets you exposure to all the basics along with UI and network communication. You can work up from there. Just don't start with something so overwhelming that you can't figure it out and want to give up. That's not going to get you anywhere.
The best advice is: work on a project that you have personal interest in. Something based on your hobbies, maybe.
If that doesn't work, make a blogging / CMS engine. Or an online photo album. Or an eStore. The world doesn't really need another of any of these things, but it will give you some good practical experience with JavaEE.
Another benefit of "re-inventing the wheel" (for learning) is that you have probably already used systems like these described above, and you have a good idea of how it can work, and maybe you have your own ideas of how it could work better. That can make requirements much simpler, and also will give you a sort of benchmark so you can see how close you can come to building a tool like the "real" ones out there. And if yours is really great, well, maybe release it and see what happens. ;)
There are many Java-based projects on SourceForge. Tinker with one you find interesting.
I've implemented either a betting pool or a Baccarat game in almost every language I've
learned.
This type of software covers:
Dates and times, with calculations
Currency types and things that can be converted to and from currency.
A discrete set of rules that is easy to test
States, transition between states and multiple entities responsible for state transition
Multiple users with different views of the same model End conditions
Multiple player blackjack and poker would work also.
One caveat is that in my day job I work on financial systems and there is a huge overlap
between things to consider when writing a multiplayer game of chance and a trading system.
build an address book. the concept is simple, so you're not stuck on "what" to write. You can focus on learning your chosen language. You get experience in working with a database, java ( insert any language here), and UI design.
when you decide to learn another language you can create the same thing. Since the database has been created already, you can focus on the language itself.
the concept of inputting data, storing data, and retrieving data is central to a lot of applications.
Have a look around http://openhatch.org/ for a project that sounds interesting.
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I've noticed many questions on here from new programmers that can be solved using libraries. When a library is suggested, often times they respond "I don't want to use X library" Is it the learning curve? or ? Just curious!
A lot of new programmers are still working at a very low level of abstraction, learning the trade. That's something everyone has to go through. It takes a while to "move up the stack" so to speak.
Once programmers realise that they spend most of the time solving the same problems as someone else already did, and the goal is to realise "business value", then they can really appreciate the value a good library brings.
When you're still learning the ins and outs of a new language, also having to learn how to use a 3rd party library can look like too much work. Also, libraries tend to be badly documented - or at least have documentation that seems totally opaque to a new(er) programmer.
So, faced with trying to solve problem X, saying "use a library" can sound a lot like "solve problem Y THEN problem x".
(Also, their professors told them not to. I managed to get all the way though my undergrad in C++ without learning the STL existed. Boy, did THAT cook my noodle.)
Some people, when confronted with a
problem, think “I know, I'll use a
library.” Now they have two
problems.
Seriously - this is a reasonable way for a newbie, already overwhelmed by new language, programming environment, paradigms, keystrokes, etc. to react to the suggestion to use a library. If you've got a solution, but it's not working, there are many potential sources of error; sorting through them is a challenge. Adding to them can seem irrational.
"Use a library" means find the library, download it, install it in your project, and call the necessary function. Not hard, if you're used to it (and there aren't corporate policies against it, and you have reason to trust the vendor, and the library itself has minimal dependencies, etc.). But if it's all new to you, when you ask a programming question and get back a system configuration answer, it can seem unhelpful (even if it is not, in fact).
Almost always it's because their professor has told them that they can't.
Sometimes it's just because they want to learn it themselves, but I'd say that's rare.
It's the learning curve.
Using libraries is probably one of the worst things a learning programmer can do. Instead of learning how to code, they're learning how to use specific APIs that other people implemented. I'm not saying that every programmer has to understand every single thing that they use, but programmers who know the ins and outs of a computer (digital logic, assembling op-codes, etc) usually have an edge over people who've started with something like Java Swing and are just throwing together libraries.
In production, this is a different matter of course. But I think the best course of education is to 'make everything' once, at least. Writing my own web application framework from the ground up really improved my programming skills and abstract abilities. Doesn't mean I'll use that framework if someone hires me to build them an application, but I know the strengths, weaknesses, and reasons behind the things that the 'giant' frameworks use, and it can help me choose a particular framework for a particular situation.
I remember shying away from several libraries simply because I wanted to see if I could create my own algorithm. I didn't want to just give up and let someone do the work for me but rather I wanted to learn from my mistakes. Once I had come up with a solution I was happy with, I looked into the libraries.
So for me it was simply wanting to see if I could do it.
I always have this urge to do it myself, but sometimes I can see my own limitations.
Just recently downloaded a library to create PDF documents, but thats pretty much the only time I can remember.
At least for me, (trying to) do things myself, is my way of learning.
My impression is that many newbie programmers wouldn't consider it their own work if they were to use someone elses libraries.
I don't think that this is necessarily a bad thing. Using libraries is great; it saves time, effort, bugs, etc. However, you learn very little in the process, and for new programmers, learning is the goal. To answer the question, I think that they tend to shy way from libraries simply because they are not used to using them and perhaps they don't know that they exist.
For many poorly documented libraries that are either implemented loosely or in languages that don't allow you to control containment and visibility very well, it can be quite difficult to guess just how the library is supposed to be used.
After you've used it for a while, you've gotten used to the quirks or read other source code that taught you the right way; but until then it can be pretty irritating to use a poorly put-together/designed library. (or even a well designed one that isn't terribly well documented).
If you don't have the source code to the library, that's another problem--you have no control over the ability to keep your program working. This is much more rare these days, but still happens in the case of a purchased library.
Most of the points covered off (for me the main one is the learning curve) but one other I think plays a part:
Because learning about a library is less exciting than coding the same functionality yourself.
More libraries = less billable hours.
I think there's a lot of time that needs to be invested in understanding the library's purpose - yes, a learning curve, but it's more that newbie programmers probably don't know what they need until they have a lot more experience.
Because it's fun.
Because part of maturing as a developer is learning to quickly identify problems which can be solved by a library or existing solution and which need personal attention.
When you're trying to learn how to do things, anytime something is accomplished "magically" by calling AwesomeClass.doAwesomeStuff(), you end up giving away a portion of control. When you are "new" and don't know what you're giving away or why it can be unsettling. This was my primary knock against Rails when I was first learning it. So many things just "worked" and I didn't know why without digging through lots of Rails source (which I generally didn't have time to do).
At least, that's my take on it.
The same reason that more experienced developers do -
Because it can often be as difficult to learn how to use a library as to write the part of it you need yourself. And at least then you can understand how it works when it doesn't do what you expect.
An experienced developer just has experience at understanding how to use libraries so more likely to consider it. An inexperienced developer it's one more thing to learn...
I'm a programmer, not a psychologist! :)
It was a long, long time ago for me, but it was because I wanted to learn and experience. I didn't want to use something I did not understand, so if I didn't think I understood the library and could program it myself, I tried not to use it. There might have been a bit of fear too; programming gives you a feeling of control, and using a library is like giving away this control.
Answer from a noob -
"I am not sure how to use the libraries or even how to access them or how it works"
Libraries often come with the overhead of learning some API and it's paradigm. It can get complex fairly quickly, and I could easily understand that beginners would prefer something a bit more in their comfort zone. From my experience, I found most libraries & frameworks seem to do a great job abstracting some tedious routine, but when I need to either extend this functionality, or use it in a way that's not intended, it can be a handful.
I think it's one of those things where "practice makes perfect".
Well, the newbie's purpose might be more solving the problem than implementing a solution. Perhaps what they really want to do is figure out how to solve the problem. I mean, if they're still heavily in the learning phase, it's quite possible they don't want easy answers handed to them.
I think the professors want them to stick to the basics. When I graduated from under-grad school, I knew C++, Java and some other languages but had no clue about libraries and frameworks being used in companies. It was like do you know java..yes..can you write a servlet..no.
For speed demons they rarely use 3rd party libraries and new programmers are usually looking to squeeze every once of speed of of their code. I think if they don't have control over their code they can't get the performance that they are looking for. At least thats why i avoided libraries when I first started to program.
I remember programing my first DAL and avoided all the other free libraries out on the web because I wanted my code to perform at top speed. Later, I discovered that usually its not the code thats the bttleneck its actually the database.
Some open source libraries are buggy or not as efficient as others.
In my eyes another factor is that additional libraries add complexity. Programs tend to get harder to understand, harder to maintain and buggier when getting more complex. I think what makes especially new programmers shy away from libraries is that adding library code increases complexity more than adding your own code - simply because understanding how the library works is still out of their grasp. So it seems to be a problem of both skill and psychology.
I think more fundamental issues can be recognized as a deterrant to using existing libraries.
Part of this as "newbie programmers" is a lack of exposure to libraries. If you don't know they exist, how do you know to use them?
Number Of Options Available. Let's say I'm really interested in learning more about MVC, but if I have to choose between cakephp and smarty and zend and ... well you can quickly see the gears work to discover a way to achieve the goal without investing the time experimenting. Take a look at Freshmeat or SourceForge to get a better understanding at the daunting selection of libraries available.
Questionable support combined with sketchy/outdated documentation for the libraries. Do I want to use this tool that may no longer work or may be abandoned in the future? It is likely that a project will evolve, and so it will for the project of a library too. Will its usefulness last the lifetime of my project or will I be required to re-do this work again?
Using a library requires you to understand the relatively complex design of the library, something that new programmers might not have mastered because all they've ever written is simple/procedural/single-purpose code. For example, to an experienced programmer standard design patterns like template method, observer and command seem pretty obvious, but to a newbie it all just seems like magic and/or unnecessary complexity. For me the turning point was when I got good enough to grok design patterns and write some basic reusable code.
It's been a long time now, but when I came out of college, I knew nothing of libraries. This was in the days of mainframes and mini-computers. Our college had a VAX and the managers were paranoid about students hacking the system, so didn't allow us to even see the library manuals. So, when I first came out of college, I didn't even think of libraries being available.
I am sure there are a lot of reasons why the newbie doesn't want to use the new library. But wouldn't this be a good opportunity, if you have enough time, to show them what the advantage of using the library is? With the people I work with, I will usually provide an example of why something is better than their approach. It helps them learn and mature as a programmer.
Happens that noobs use Libs without knowing, but when they must import/add one that is fairly less documented, there is a fear of unknow. That happens mostly for compiled langs!
In the interpreted, (or compiled IRT), mainly when there is a console, such fear is almost non-existent; since you can require and see if it fails, call a method and see what it returns.
Consoles are tools of bravery !
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I've been coding since my early teenager years. I started out with HTML, went on to PHP/MySQL (created my own forums, social networking sites, etc..) and then branched out into more traditional languages such as Java and C++ (also picked up a little VB .NET in high school). I'm most familiar now with C++ as that is the language of choice taught to us in Computer Science II (skipped Comp Sci I) at RPI. I now feel like I have a very good knowledge of how to program from this class (the homework assignments were brutal).
It is now summer and I am interning at a company that is providing me some level of new experiences with programming, but I want more. I want to feel the incredible satisfaction that I got out of my computer classes at RPI whenever I finished a long assignment (generating every possible wordsearch from a set of words to include and exclude comes to mind).
My question is, where do I go from here? I tried following a tutorials online, but they were all too simple. I then tried heading over to sourceforge and helping out with various projects. But, as soon as I downloaded the code I got lost in its complexity. I have never created actual software of a real life applicapable scale. And I don't know where to get started. How do you transition from programming knowledge to actuall creation of software?
I'm also open to learning new languages (javascript/jQuery, ASP .NET, C#, Python), or using new libraries and/or frameworks with c++ (we only used the STL in Comp Sci II) and other languages. Again my question is, where do I go from here? And I am welcome to all possible answers.
Thanks Much,
Michael
You could join a big open source project, you'll learn a lot and accomplish something cool.
EDIT after comment: If this is too complicated for you, try starting a "real" project. I say "real" because it should be something that you want to do, not a "create a blog" or "how to do a loop". For instance last year I created a fully functional project management system that I now use for some of my projects. If this is real, you will be more motivated and you will want to get this done.
Pick the technology you want for it. I'd recommend Ruby on Rails because it's awesome and full of interesting concepts that will improve the way you code overtime (DRY, RESTful, MVC...)... but you can pick whatever you want.
Try to create your project using what you know and basic tutorials. You will get stuck and have to learn some more in order to get the features you want going. To me that's the best way to improve the way you code and general programming knowledge.
Since you'll start the project from scratch, you'll see where to start and how this will evolve. I'll take the project management tool. We started with "A project has todos" and we ended up with all kind of other features such as a complex calendar, a full ajax interface, a embedded chat...
Once you see how you did this, try doing the same with a friend of yours to get a fealing of teamwork in development. Learn how to use SVN, basecamp... learn about software development processes (Agile!), peer programming..
There's a lot to experience! Then you could give open source another try.
Hope that helps
I'd recommend trying a pure functional language, such as Haskell. It's a completely different way of looking at programming, and I found it very satisfying.
I recommend the book Real World Haskell for learning it.
Edit: In response to comments, my interpretation of the question is where can he go from here as a programmer. Functional programming is a logical direction. For someone learning functional programming for the first time, Haskell is nice because it doesn't really allow for imperative programming practices. Furthermore, it has basically all features you will find in other functional languages, which means it will be easy to pick up other functional languages.
I would suggest looking at Project Euler. It's a great and fun way to learn a new language, and it does provide that level of satisfaction when you solve the problems. They offer a huge range of problems at all levels of difficulty.
I think the best way to improve your skills as a programmer is to do what programming was intended for: solve problems. I'm sure you've been playing around on your machine and at one time thought to yourself "I wish there was a program that did this..." or "I wonder if there are any programs that do X..." Instead of just googling to see if someone else wrote it, write it yourself. Start with something small, and gradually make it more complex. Add features. Allow yourself to fail, and when you do, ask yourself (or us at stackoverflow) how to overcome that obstacle. Once you have the basics of programming, everything else is just making big things out of littler things, and the little things are usually pretty easy.
When you are making something you know you will actually use, it's more fun and more gratifying when you finish.
Do you understand all of the following and how they work?
Linked lists (single and double)
Sequential vs. binary search
Binary trees
Stacks
Red-black trees
Algorithmic complexity and big O notation
Recursion
Hash tables and hashing algorithms
If you don't feel completely conversant in any of these, take a class in data structures and algorithms.
It seems like you've experienced many languages, but have not created a real-world application. Creating software in any of those languages will bring you to a new level.
PS: Creating software is much more than just knowing how to mess around with a language.
Check out Design Patterns.
I believe that's beyond mere simple coding.
You could offer your abilities to a non profit or a friend or someone who needs a website or program built.
Tell them you can do it for free and then just go for it. As you start to make it you'll start to see what you need to learn.
For example I bit ago I had the program Peel www.getpeel.com on my Mac. But sold my Mac for Wind as I am traveling.
Seeing that there was nothing for Windows (or nothing I could find) like Peel. I build my own in PHP and am up to a 4th rebuilding of it as I learn betters ways to do each new thing I am learning.
You've got to find a particular type of functionality that interests you. For me it's been basic socket programming and making my own protocols. I got that feeling when I was able to create a functional file uploading control that worked in conjunction with a file upload service on the server which I had created. The protocol handles authentication, chunking and hash comparison. Sometime soon I plan on incorporating file-resume functionality as well.
Well my advice will be to find a problem/project you are interested in and try to code it. Trying a real problem is something that drives you. Find something not to complex but not too simple. Something to try when starting a new language is to write some tools. You can for example program a python script that print metrics on a C++ project. You can write a tool that extract some statistics from a website you use, etc. When I learn programming game programming was quite fun (I was young :-) ). You can try to program some simple game using a 3D engine like Ogre3D for example. Participate in an opensource project is great too but as you stated perhaps a bit overwhelming for now ;-)
Find something you like and that has a REAL useful goal for you. You will thrive to solve the problem and learn a lot along the way !
I think the transition from the kind of finite tractable problems that are part of class projects (and some internships) to "real world" projects is quite tough. Sounds like language syntax, getting bugs out of code etc. is something you are comforatble with.
When we come to larger projects, probably with many release cycles, with developers working together, different kinds of problems emerge. I remember being shocked when I saw my first big project plan - what a small propertion of the time was actually writing code!
The thing I found helpful as a junior was "Sitting By Nelly", I was lucky enough to work for enlighted employers who put me with very experienced and helpful developers. Sometimes to work with, sometime to work alongside. I reckon that helped me get over the hurdles you describe.
So, I reckon you need to find employment of this kind. Be less concerned about specific technologies, salary etc. Look instead for the culture and level of responsibility you would have.
I think you should really start a "real world application" as suggested here. You will see that a real project requires a bit more than just knowing the language.
I suggest you find some simple problem you had issue with, and make a software that solves that issue.
For example, if you want some kind of software that checks RSS feeds every 5 minutes and makes a little pop-up as soon as a new one comes along. Or you want a program that will let you do simple presentations by just dragging a few pictures in.
Then whatever you choose, start by making the simple solution to the problem and extend from there (like do different settings, extra features etc.)
I've looked for the answer to this question for a while now. Most all of the suggestions are usually either help an open source project or build something that interests you. I'm starting to realize that those answers are vague because what's 'interesting' or 'valuable' experience and how to get started doing it is completely subjective. Also, there's only one way to get real experience, which is to work on real projects. It's difficult but find a project, personal, open source, or otherwise that will increase your knowledge in a technology or platform that you think will hold your interest. Then just dig in. It doesn't have to be of earth shattering importance, just valuable in relation to your own goals.
There is no magic bullet transition from academic puzzle solving programs to real world applications. The best way to learn is just to jump in head first. It will take you a very long time to learn what you need to if you only ever look at your own code. You need to be looking at code written by professionals and struggling to understand why it works the way it does until you do understand it.
It seems overwhelming at first, but you will quickly start to see patterns if the application is at all logical. Well written code will be separated in logical ways, so you should be able to pick it apart one layer at a time.
For example, you could try a bottom up approach where you try to understand how the database interactions are handled before looking at the code that uses the database layer. You keep going upward until you get to the GUI event handlers.
Large enterprise applications can be even harder to understand because there might be a lot more than one executable, or component. Try to stay focused and learn what the component is responsible for doing, and then pick it apart a piece at a time.
You will see that there are not just patterns at the function and class level, but at higher levels as well. This makes it simpler to understand what is going on when you understand those patterns.
Try to find an internship or co-op position. I was in a similar situation after my first few courses. I took a co-op position sophomore year and I learned so much more on the job than I did in class. Class is great for teaching you theory and the basics. I learned C# on my first project on my co-op and that got me my second co-op position at another employer (wanted to see how it was working at a small company).
This past spring, I accepted a position at my first co-op employer, reworking my first major project I had started on my co-op. I have a list of side projects I also want to complete, which will help round out my skills, as well as learn some other languages.
So my suggestion is try finding a job where you can have a great mentor. On my second co-op, I learned alot of the coding standards that I code against from my supervisor. He was a great teacher, and really had some great input, and explained why things should be done certain ways.
You will almost certainly go nowhere unless you find something that interests you. Figure out what is interesting, and then how to write software involving it.
The only way to begin is to begin! There is really no other way... The best answers you get would always tell you this. You have the knowledge, now put it to work!
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One thing I struggle with is planning an application's architecture before writing any code.
I don't mean gathering requirements to narrow in on what the application needs to do, but rather effectively thinking about a good way to lay out the overall class, data and flow structures, and iterating those thoughts so that I have a credible plan of action in mind before even opening the IDE. At the moment it is all to easy to just open the IDE, create a blank project, start writing bits and bobs and let the design 'grow out' from there.
I gather UML is one way to do this but I have no experience with it so it seems kind of nebulous.
How do you plan an application's architecture before writing any code? If UML is the way to go, can you recommend a concise and practical introduction for a developer of smallish applications?
I appreciate your input.
I consider the following:
what the system is supposed to do, that is, what is the problem that the system is trying to solve
who is the customer and what are their wishes
what the system has to integrate with
are there any legacy aspects that need to be considered
what are the user interractions
etc...
Then I start looking at the system as a black box and:
what are the interactions that need to happen with that black box
what are the behaviours that need to happen inside the black box, i.e. what needs to happen to those interactions for the black box to exhibit the desired behaviour at a higher level, e.g. receive and process incoming messages from a reservation system, update a database etc.
Then this will start to give you a view of the system that consists of various internal black boxes, each of which can be broken down further in the same manner.
UML is very good to represent such behaviour. You can describe most systems just using two of the many components of UML, namely:
class diagrams, and
sequence diagrams.
You may need activity diagrams as well if there is any parallelism in the behaviour that needs to be described.
A good resource for learning UML is Martin Fowler's excellent book "UML Distilled" (Amazon link - sanitised for the script kiddie link nazis out there (-: ). This book gives you a quick look at the essential parts of each of the components of UML.
Oh. What I've described is pretty much Ivar Jacobson's approach. Jacobson is one of the Three Amigos of OO. In fact UML was initially developed by the other two persons that form the Three Amigos, Grady Booch and Jim Rumbaugh
I really find that a first-off of writing on paper or whiteboard is really crucial. Then move to UML if you want, but nothing beats the flexibility of just drawing it by hand at first.
You should definitely take a look at Steve McConnell's Code Complete-
and especially at his giveaway chapter on "Design in Construction"
You can download it from his website:
http://cc2e.com/File.ashx?cid=336
If you're developing for .NET, Microsoft have just published (as a free e-book!) the Application Architecture Guide 2.0b1. It provides loads of really good information about planning your architecture before writing any code.
If you were desperate I expect you could use large chunks of it for non-.NET-based architectures.
I'll preface this by saying that I do mostly web development where much of the architecture is already decided in advance (WebForms, now MVC) and most of my projects are reasonably small, one-person efforts that take less than a year. I also know going in that I'll have an ORM and DAL to handle my business object and data interaction, respectively. Recently, I've switched to using LINQ for this, so much of the "design" becomes database design and mapping via the DBML designer.
Typically, I work in a TDD (test driven development) manner. I don't spend a lot of time up front working on architectural or design details. I do gather the overall interaction of the user with the application via stories. I use the stories to work out the interaction design and discover the major components of the application. I do a lot of whiteboarding during this process with the customer -- sometimes capturing details with a digital camera if they seem important enough to keep in diagram form. Mainly my stories get captured in story form in a wiki. Eventually, the stories get organized into releases and iterations.
By this time I usually have a pretty good idea of the architecture. If it's complicated or there are unusual bits -- things that differ from my normal practices -- or I'm working with someone else (not typical), I'll diagram things (again on a whiteboard). The same is true of complicated interactions -- I may design the page layout and flow on a whiteboard, keeping it (or capturing via camera) until I'm done with that section. Once I have a general idea of where I'm going and what needs to be done first, I'll start writing tests for the first stories. Usually, this goes like: "Okay, to do that I'll need these classes. I'll start with this one and it needs to do this." Then I start merrily TDDing along and the architecture/design grows from the needs of the application.
Periodically, I'll find myself wanting to write some bits of code over again or think "this really smells" and I'll refactor my design to remove duplication or replace the smelly bits with something more elegant. Mostly, I'm concerned with getting the functionality down while following good design principles. I find that using known patterns and paying attention to good principles as you go along works out pretty well.
http://dn.codegear.com/article/31863
I use UML, and find that guide pretty useful and easy to read. Let me know if you need something different.
UML is a notation. It is a way of recording your design, but not (in my opinion) of doing a design. If you need to write things down, I would recommend UML, though, not because it's the "best" but because it is a standard which others probably already know how to read, and it beats inventing your own "standard".
I think the best introduction to UML is still UML Distilled, by Martin Fowler, because it's concise, gives pratical guidance on where to use it, and makes it clear you don't have to buy into the whole UML/RUP story for it to be useful
Doing design is hard.It can't really be captured in one StackOverflow answer. Unfortunately, my design skills, such as they are, have evolved over the years and so I don't have one source I can refer you to.
However, one model I have found useful is robustness analysis (google for it, but there's an intro here). If you have your use-cases for what the system should do, a domain model of what things are involved, then I've found robustness analysis a useful tool in connecting the two and working out what the key components of the system need to be.
But the best advice is read widely, think hard, and practice. It's not a purely teachable skill, you've got to actually do it.
I'm not smart enough to plan ahead more than a little. When I do plan ahead, my plans always come out wrong, but now I've spend n days on bad plans. My limit seems to be about 15 minutes on the whiteboard.
Basically, I do as little work as I can to find out whether I'm headed in the right direction.
I look at my design for critical questions: when A does B to C, will it be fast enough for D? If not, we need a different design. Each of these questions can be answer with a spike. If the spikes look good, then we have the design and it's time to expand on it.
I code in the direction of getting some real customer value as soon as possible, so a customer can tell me where I should be going.
Because I always get things wrong, I rely on refactoring to help me get them right. Refactoring is risky, so I have to write unit tests as I go. Writing unit tests after the fact is hard because of coupling, so I write my tests first. Staying disciplined about this stuff is hard, and a different brain sees things differently, so I like to have a buddy coding with me. My coding buddy has a nose, so I shower regularly.
Let's call it "Extreme Programming".
"White boards, sketches and Post-it notes are excellent design
tools. Complicated modeling tools have a tendency to be more
distracting than illuminating." From Practices of an Agile Developer
by Venkat Subramaniam and Andy Hunt.
I'm not convinced anything can be planned in advance before implementation. I've got 10 years experience, but that's only been at 4 companies (including 2 sites at one company, that were almost polar opposites), and almost all of my experience has been in terms of watching colossal cluster********s occur. I'm starting to think that stuff like refactoring is really the best way to do things, but at the same time I realize that my experience is limited, and I might just be reacting to what I've seen. What I'd really like to know is how to gain the best experience so I'm able to arrive at proper conclusions, but it seems like there's no shortcut and it just involves a lot of time seeing people doing things wrong :(. I'd really like to give a go at working at a company where people do things right (as evidenced by successful product deployments), to know whether I'm a just a contrarian bastard, or if I'm really as smart as I think I am.
I beg to differ: UML can be used for application architecture, but is more often used for technical architecture (frameworks, class or sequence diagrams, ...), because this is where those diagrams can most easily been kept in sync with the development.
Application Architecture occurs when you take some functional specifications (which describe the nature and flows of operations without making any assumptions about a future implementation), and you transform them into technical specifications.
Those specifications represent the applications you need for implementing some business and functional needs.
So if you need to process several large financial portfolios (functional specification), you may determine that you need to divide that large specification into:
a dispatcher to assign those heavy calculations to different servers
a launcher to make sure all calculation servers are up and running before starting to process those portfolios.
a GUI to be able to show what is going on.
a "common" component to develop the specific portfolio algorithms, independently of the rest of the application architecture, in order to facilitate unit testing, but also some functional and regression testing.
So basically, to think about application architecture is to decide what "group of files" you need to develop in a coherent way (you can not develop in the same group of files a launcher, a GUI, a dispatcher, ...: they would not be able to evolve at the same pace)
When an application architecture is well defined, each of its components is usually a good candidate for a configuration component, that is a group of file which can be versionned as a all into a VCS (Version Control System), meaning all its files will be labeled together every time you need to record a snapshot of that application (again, it would be hard to label all your system, each of its application can not be in a stable state at the same time)
I have been doing architecture for a while. I use BPML to first refine the business process and then use UML to capture various details! Third step generally is ERD! By the time you are done with BPML and UML your ERD will be fairly stable! No plan is perfect and no abstraction is going to be 100%. Plan on refactoring, goal is to minimize refactoring as much as possible!
I try to break my thinking down into two areas: a representation of the things I'm trying to manipulate, and what I intend to do with them.
When I'm trying to model the stuff I'm trying to manipulate, I come up with a series of discrete item definitions- an ecommerce site will have a SKU, a product, a customer, and so forth. I'll also have some non-material things that I'm working with- an order, or a category. Once I have all of the "nouns" in the system, I'll make a domain model that shows how these objects are related to each other- an order has a customer and multiple SKUs, many skus are grouped into a product, and so on.
These domain models can be represented as UML domain models, class diagrams, and SQL ERD's.
Once I have the nouns of the system figured out, I move on to the verbs- for instance, the operations that each of these items go through to commit an order. These usually map pretty well to use cases from my functional requirements- the easiest way to express these that I've found is UML sequence, activity, or collaboration diagrams or swimlane diagrams.
It's important to think of this as an iterative process; I'll do a little corner of the domain, and then work on the actions, and then go back. Ideally I'll have time to write code to try stuff out as I'm going along- you never want the design to get too far ahead of the application. This process is usually terrible if you think that you are building the complete and final architecture for everything; really, all you're trying to do is establish the basic foundations that the team will be sharing in common as they move through development. You're mostly creating a shared vocabulary for team members to use as they describe the system, not laying down the law for how it's gotta be done.
I find myself having trouble fully thinking a system out before coding it. It's just too easy to only bring a cursory glance to some components which you only later realize are much more complicated than you thought they were.
One solution is to just try really hard. Write UML everywhere. Go through every class. Think how it will interact with your other classes. This is difficult to do.
What I like doing is to make a general overview at first. I don't like UML, but I do like drawing diagrams which get the point across. Then I begin to implement it. Even while I'm just writing out the class structure with empty methods, I often see things that I missed earlier, so then I update my design. As I'm coding, I'll realize I need to do something differently, so I'll update my design. It's an iterative process. The concept of "design everything first, and then implement it all" is known as the waterfall model, and I think others have shown it's a bad way of doing software.
Try Archimate.