How do I decide for class responsibilities?
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It is confusing if you concentrate on one item to the exclusion of all else. Take your example; you have a statement that "a blog entry has to have a title and a body". Okay, I can see where you are going with that, but you're now wondering whether or not you violate SOLID to have a body element AND a title element. This is designing in isolation. You need to consider the other requirements to see what effect they have. For instance, suppose you have a requirement that states that a title must have more than 20 characters and less than 150 characters. Does this mean that you need to create a separate Title class which encapsulates the rules, or do you make it part of the BlogEntry class? Well, that depends - you might want to create a separate validation engine which is responsible for enforcing the rules, in which case you would probably just use attributes on your BlogEntry properties, so the mechanism for defining HOW to validate the properties is external, but the rules for each element are attached (this is a common technique). Then you need to consider where your rules are applied. Do you do everything in your UI, or do you abstract to a business rules class? Is your BlogEntry class actually a model instead? Should you use MVC? The thing I'm trying to get at here is that there is no "one size fits all" solution. As others have said, it's experience, but it is also a case that your start and end point has to be "what do I need to put in to satisfy the requirements?" By all means, consider the use cases - a well architected use case should be a vital part of developing your application because it should tell you how the user will actually use your application. Beyond that, adhering to SOLID is a mix of experience and common sense, and you shouldn't slavishly adhere to something just because someone else has written about how good it is.
*pre-emptive celebratory nipple tassle jiggle* - Sean Ewington
"Mind bleach! Send me mind bleach!" - Nagy Vilmos
CodeStash - Online Snippet Management | My blog | MoXAML PowerToys | Mole 2010 - debugging made easier
Intelligence without being a third year undergraduate! How the fock did you do that?
Panic, Chaos, Destruction. My work here is done. Drink. Get drunk. Fall over - P O'H OK, I will win to day or my name isn't Ethel Crudacre! - DD Ethel Crudacre I cannot live by bread alone. Bacon and ketchup are needed as well. - Trollslayer Have a bit more patience with newbies. Of course some of them act dumb - they're often *students*, for heaven's sake - Terry Pratchett
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Right. At your university they never taught you in the advanced English class about the Dilbert principle? This happens in real life too, you know? Hence the principle. I know some people who get paid very highly and I chat with them for about 50% of the time I'm taking lectures. What does this imply? Well, it implies that they are sitting on their chair all day being lazy and getting paid huge salaries (because I know his function). It used to be that the really hard working and intelligent people were bumped up to manager. Now it's the other way around. If you really believe that hard working smart people get the better salaries, you're wrong. I've experienced nothing like it in the real world. I've worked before as well. I've been programming on a 3 month contract in a company my university suggested. The programmers were just absolutely horrible and cynical people. They were also not very bright. I knew more about programming and computers than they did. Anyway not to drift off the point here. Experience certainly may help in the IT industry of today, but if it wasn't for my university's high reputation (because they have excellent courses and professors) I wouldn't even have had the slightest chance to function as a temporary programmer in a company. I tried before. You have no idea how many 'no' answers I got. Meanwhile, a top paid programmer I know who works for one of the best software development companies can only type with two fingers and can't even do a copy paste in Excel! How fair is that?! Yes, what a world. With hard work you get somewhere.. please.
Did your super duper university not teach you what a paragraph is? Legibility. Learn the word and learn it quickly!
Panic, Chaos, Destruction. My work here is done. Drink. Get drunk. Fall over - P O'H OK, I will win to day or my name isn't Ethel Crudacre! - DD Ethel Crudacre I cannot live by bread alone. Bacon and ketchup are needed as well. - Trollslayer Have a bit more patience with newbies. Of course some of them act dumb - they're often *students*, for heaven's sake - Terry Pratchett
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Intelligence without being a third year undergraduate! How the fock did you do that?
Panic, Chaos, Destruction. My work here is done. Drink. Get drunk. Fall over - P O'H OK, I will win to day or my name isn't Ethel Crudacre! - DD Ethel Crudacre I cannot live by bread alone. Bacon and ketchup are needed as well. - Trollslayer Have a bit more patience with newbies. Of course some of them act dumb - they're often *students*, for heaven's sake - Terry Pratchett
I probably knicked it from someone clever. And I'm someone who hasn't got a computer degree - largely self taught. I don't think it's done me any harm.
*pre-emptive celebratory nipple tassle jiggle* - Sean Ewington
"Mind bleach! Send me mind bleach!" - Nagy Vilmos
CodeStash - Online Snippet Management | My blog | MoXAML PowerToys | Mole 2010 - debugging made easier
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CsTreval wrote:
I come from a university with one of the highest reputations there are.
Soon to be lowest.
CsTreval wrote:
I'm actually going to be an Application Developer.
With this attitude you are bound to go far.
Undergraduates are so sweet when they think they know things.
Panic, Chaos, Destruction. My work here is done. Drink. Get drunk. Fall over - P O'H OK, I will win to day or my name isn't Ethel Crudacre! - DD Ethel Crudacre I cannot live by bread alone. Bacon and ketchup are needed as well. - Trollslayer Have a bit more patience with newbies. Of course some of them act dumb - they're often *students*, for heaven's sake - Terry Pratchett
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I probably knicked it from someone clever. And I'm someone who hasn't got a computer degree - largely self taught. I don't think it's done me any harm.
*pre-emptive celebratory nipple tassle jiggle* - Sean Ewington
"Mind bleach! Send me mind bleach!" - Nagy Vilmos
CodeStash - Online Snippet Management | My blog | MoXAML PowerToys | Mole 2010 - debugging made easier
I got my 'putin' degree only last year - after 25+ years - to find out what's new. Very little is the answer.
Panic, Chaos, Destruction. My work here is done. Drink. Get drunk. Fall over - P O'H OK, I will win to day or my name isn't Ethel Crudacre! - DD Ethel Crudacre I cannot live by bread alone. Bacon and ketchup are needed as well. - Trollslayer Have a bit more patience with newbies. Of course some of them act dumb - they're often *students*, for heaven's sake - Terry Pratchett
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I got my 'putin' degree only last year - after 25+ years - to find out what's new. Very little is the answer.
Panic, Chaos, Destruction. My work here is done. Drink. Get drunk. Fall over - P O'H OK, I will win to day or my name isn't Ethel Crudacre! - DD Ethel Crudacre I cannot live by bread alone. Bacon and ketchup are needed as well. - Trollslayer Have a bit more patience with newbies. Of course some of them act dumb - they're often *students*, for heaven's sake - Terry Pratchett
I believe most of it is just fancy names for what we were doing anyway.
*pre-emptive celebratory nipple tassle jiggle* - Sean Ewington
"Mind bleach! Send me mind bleach!" - Nagy Vilmos
CodeStash - Online Snippet Management | My blog | MoXAML PowerToys | Mole 2010 - debugging made easier
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Did your super duper university not teach you what a paragraph is? Legibility. Learn the word and learn it quickly!
Panic, Chaos, Destruction. My work here is done. Drink. Get drunk. Fall over - P O'H OK, I will win to day or my name isn't Ethel Crudacre! - DD Ethel Crudacre I cannot live by bread alone. Bacon and ketchup are needed as well. - Trollslayer Have a bit more patience with newbies. Of course some of them act dumb - they're often *students*, for heaven's sake - Terry Pratchett
He didn't actually say what the University's reputation was for, just that it was the highest.
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I believe most of it is just fancy names for what we were doing anyway.
*pre-emptive celebratory nipple tassle jiggle* - Sean Ewington
"Mind bleach! Send me mind bleach!" - Nagy Vilmos
CodeStash - Online Snippet Management | My blog | MoXAML PowerToys | Mole 2010 - debugging made easier
The one thing I found fascinating was Systems Theory[^]. It has nothing to do what you think and is a complete mind fock until you get the little light come on...
Panic, Chaos, Destruction. My work here is done. Drink. Get drunk. Fall over - P O'H OK, I will win to day or my name isn't Ethel Crudacre! - DD Ethel Crudacre I cannot live by bread alone. Bacon and ketchup are needed as well. - Trollslayer Have a bit more patience with newbies. Of course some of them act dumb - they're often *students*, for heaven's sake - Terry Pratchett
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He didn't actually say what the University's reputation was for, just that it was the highest.
Top for arrests? Absenteeism? We may never know... :-D
Panic, Chaos, Destruction. My work here is done. Drink. Get drunk. Fall over - P O'H OK, I will win to day or my name isn't Ethel Crudacre! - DD Ethel Crudacre I cannot live by bread alone. Bacon and ketchup are needed as well. - Trollslayer Have a bit more patience with newbies. Of course some of them act dumb - they're often *students*, for heaven's sake - Terry Pratchett
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The one thing I found fascinating was Systems Theory[^]. It has nothing to do what you think and is a complete mind fock until you get the little light come on...
Panic, Chaos, Destruction. My work here is done. Drink. Get drunk. Fall over - P O'H OK, I will win to day or my name isn't Ethel Crudacre! - DD Ethel Crudacre I cannot live by bread alone. Bacon and ketchup are needed as well. - Trollslayer Have a bit more patience with newbies. Of course some of them act dumb - they're often *students*, for heaven's sake - Terry Pratchett
That looks interesting. I might do some digging around into that.
*pre-emptive celebratory nipple tassle jiggle* - Sean Ewington
"Mind bleach! Send me mind bleach!" - Nagy Vilmos
CodeStash - Online Snippet Management | My blog | MoXAML PowerToys | Mole 2010 - debugging made easier
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That looks interesting. I might do some digging around into that.
*pre-emptive celebratory nipple tassle jiggle* - Sean Ewington
"Mind bleach! Send me mind bleach!" - Nagy Vilmos
CodeStash - Online Snippet Management | My blog | MoXAML PowerToys | Mole 2010 - debugging made easier
It's fun when you look at a problem domain and actually find that the best solution is to not use computers but to go back to a manual solution. The simplest description is that you look for a single small step to improve the situation, then go back and repeat until you reach an acceptable situation without knowing what the solution will eb when you start. As I said, it's brain fick to start with until you have an epiphany.
Panic, Chaos, Destruction. My work here is done. Drink. Get drunk. Fall over - P O'H OK, I will win to day or my name isn't Ethel Crudacre! - DD Ethel Crudacre I cannot live by bread alone. Bacon and ketchup are needed as well. - Trollslayer Have a bit more patience with newbies. Of course some of them act dumb - they're often *students*, for heaven's sake - Terry Pratchett
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Top for arrests? Absenteeism? We may never know... :-D
Panic, Chaos, Destruction. My work here is done. Drink. Get drunk. Fall over - P O'H OK, I will win to day or my name isn't Ethel Crudacre! - DD Ethel Crudacre I cannot live by bread alone. Bacon and ketchup are needed as well. - Trollslayer Have a bit more patience with newbies. Of course some of them act dumb - they're often *students*, for heaven's sake - Terry Pratchett
We should be told; time for a judicial inquiry.
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We should be told; time for a judicial inquiry.
Nah. Let's just have a witch hunt.
Panic, Chaos, Destruction. My work here is done. Drink. Get drunk. Fall over - P O'H OK, I will win to day or my name isn't Ethel Crudacre! - DD Ethel Crudacre I cannot live by bread alone. Bacon and ketchup are needed as well. - Trollslayer Have a bit more patience with newbies. Of course some of them act dumb - they're often *students*, for heaven's sake - Terry Pratchett
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How do I decide what types to make and what responsibilities to give them, given a design concept? Should I base myself on user stories/functional requirements in order to decide which responsibilities my classes need? It's not easy to adhere to the SOLID principle. For example I have this.. 'make a blog' assignment. I wrote down one of those functional requirements: "a blog entry has to have a title and a body". Does that mean I have to write a class Post with members Body and Title? Should a Post (BlogEntry) class only have a body and the title is supposed to be the responsibility of another class? Kind of confusing. There must be a set of rules that tell programmers how to decide on which objects to make and what responsibilities and implementation to give them. Any ideas on this? Thanks
Now to actually give you an alternate answer... While this is overly complicated for the question: Body and Title could be considered types of text components and your Post could be a 'Base Object' type that consists of a component list. In this 'silly' system, your 'Post' can easily be given any number of components because Post supports having components that have their own functions. Why not have the components as members? Well because with this idea of base objects having a list you only have to change whether you are giving the component to the object rather than modifying the member in the class. e.g. I want a new 'StupidEnemy' that has a different 'AIComponent' to the 'Enemy'. I don't have to have a new class for my new type of enemy I simply give them a different AIComponent at instantiation. I don't think this is a great approach in most cases (As you 'could' end up using a data structure to hold a single component, this seems illogical), I’ve used it a little before and it has its pros and cons but it does mean your code fits SOLID. It works quite well for game development though as it keeps the project tidy (Relative to just using straight composition).
//This is all just to represent the use of a components
BaseObject post = new Post(); //for some reason our post needs to be a subclass, again this is just a silly example.
TextComponent Header = new Header("Header"); //Best to use a uID here instead so you can potentially have multiple headers or a multimap over a vector
post.Add(Header); //Add would initialise the component to have a pointer to the Base Object
Post->getComponent("Header").SetMessage("Hello World") //get our component
//in event cycle
Post->Execute();//what ever you want to call on all components Update(), Render() etc./rant I didn't do English at University, it has no real place in a BSc also it's more of a sociology/business idea and while it does occur, I want to aim to have a better work ethic constantly for myself!/endrant
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Excuse me? I come from a university with one of the highest reputations there are. We program and work the qualitative way. This isn't one semester. It's my graduate year. I'm actually going to be an Application Developer. There's only so far you can get with 'practice' and 'experience'. Fundamental concepts and methods are far more important. That's why the top engineers get higher ranked without doing the work. Didn't you ever learn that? The tons of math and logic theory I had to process before I came to this point. The years of lectures on Software Engineering. Never underestimate the importance of scholar theory.
CsTreval wrote:
Excuse me? I come from a university with one of the highest reputations there are. We program and work the qualitative way. This isn't one semester. It's my graduate year. I'm actually going to be an Application Developer. There's only so far you can get with 'practice' and 'experience'. ... That's why the top engineers get higher ranked without doing the work. Didn't you ever learn that?
Ahh...so then why do you not already understand how to do it? Also given that you already understand that it isn't just black and white what makes you think that it can be answered in the completely general way that you asked the question?
CsTreval wrote:
There's only so far you can get with 'practice' and 'experience'. Fundamental concepts and methods are far more important.
Absolute rubbish. I have been responsible for hiring and interviewing people for more than 15 years and the PRIMARY requirement is experience. Education, even a PHD, has almost zero relevance after five years of real experience and has zero relevance when considering actual problem domain knowledge. Someone with no actual work experience would need to have a half time mentor for at least six months before they could be expected to be fully productive. True regardless of the school they went to.
CsTreval wrote:
Never underestimate the importance of scholar theory.
Nor should one over estimate it. Nor should one think that in the day to day work of creating code that "scholar[ly] theory" has much importance because most of the time it is not relevant.
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Right. At your university they never taught you in the advanced English class about the Dilbert principle? This happens in real life too, you know? Hence the principle. I know some people who get paid very highly and I chat with them for about 50% of the time I'm taking lectures. What does this imply? Well, it implies that they are sitting on their chair all day being lazy and getting paid huge salaries (because I know his function). It used to be that the really hard working and intelligent people were bumped up to manager. Now it's the other way around. If you really believe that hard working smart people get the better salaries, you're wrong. I've experienced nothing like it in the real world. I've worked before as well. I've been programming on a 3 month contract in a company my university suggested. The programmers were just absolutely horrible and cynical people. They were also not very bright. I knew more about programming and computers than they did. Anyway not to drift off the point here. Experience certainly may help in the IT industry of today, but if it wasn't for my university's high reputation (because they have excellent courses and professors) I wouldn't even have had the slightest chance to function as a temporary programmer in a company. I tried before. You have no idea how many 'no' answers I got. Meanwhile, a top paid programmer I know who works for one of the best software development companies can only type with two fingers and can't even do a copy paste in Excel! How fair is that?! Yes, what a world. With hard work you get somewhere.. please.
CsTreval wrote:
It used to be that the really hard working and intelligent people were bumped up to manager.
Sigh...what fun to be young again. I suggest you research the "Peter Principle". You will find that the copyright on the primary book that introduced that was 1969.
CsTreval wrote:
I knew more about programming and computers than they did.
One thing I knew even in college was that is was really unlikely that I know everything. And with that understanding I found that almost (if not everyone) I have ever met has given me the opportunity to learn something.
CsTreval wrote:
Meanwhile, a top paid programmer I know who works for one of the best software development companies can only type with two fingers and can't even do a copy paste in Excel!
So there are several possibilities. 1. You do not have any idea what that person actually does. 2. That specific company and/or department is a failure. 3. All companies are like that and thus you will never get a job (because they don't hire people that can program.)
CsTreval wrote:
It used to be that the really hard working and intelligent people ...I knew more about programming and computers than they did
I can't be sure but I would suppose that arrogance is one trait that will in fact lead to... - not getting hired in the first place - getting fired once hired.
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Hmm.. I learned that the method of taking out nouns and looking at verbs is incorrect. It is more abstract.
This is code design not a grammar lesson! XD But for some extent your statement is true because some of the nouns usually identify your packages or classes or the data structures you might pack into a single class. Don't rely on methods, use your brain and experience. There is no method that compensates you for not having experience so practice! practice! practice! But on my road learning code design I use the following guidline: First you have to be able to break down a problem into small pieces, then to break down those pieces into even smaller pieces. This is the most difficult step, you need some coding experience to do this. You have to be able to identify problems and patterns. This way you get a "hierarchy of problems" a "tree of those problems". The root of this tree is your program, some nodes in the tree below the root are packages, and as you go down towards the leaf nodes you will find classes sooner or later. If you break down the problems with enough granulartiy your tree will identify the package and class structure of your program too. Of course you can start this tree from a package or class level if you have to solve only a part of the problems. Now you have the classes and you have to find out what kind of data, which member variables are needed to solve the problems that belong to a class and you have to put them into the right class, the same is true for the methods that work with that data. I usually spot out bad code design in a minute, this usually involves code (method(s)) that doesn't work with the member variables of the actual class the method resides in, instead the method uses data and methods that it reaches from other objects. In this case the method should be moved to somewhere else where its most used data resides. If it uses a lot of data from here and there maybe from incoming parameters (or a lot of classes call that method) then it can be put into a helper class as a static helper method. EDIT: Another bad design is bloat code - huge monolithic classes. In this case the problem the class solves needs to be split into sub-problems and more classes.
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Right. At your university they never taught you in the advanced English class about the Dilbert principle? This happens in real life too, you know? Hence the principle. I know some people who get paid very highly and I chat with them for about 50% of the time I'm taking lectures. What does this imply? Well, it implies that they are sitting on their chair all day being lazy and getting paid huge salaries (because I know his function). It used to be that the really hard working and intelligent people were bumped up to manager. Now it's the other way around. If you really believe that hard working smart people get the better salaries, you're wrong. I've experienced nothing like it in the real world. I've worked before as well. I've been programming on a 3 month contract in a company my university suggested. The programmers were just absolutely horrible and cynical people. They were also not very bright. I knew more about programming and computers than they did. Anyway not to drift off the point here. Experience certainly may help in the IT industry of today, but if it wasn't for my university's high reputation (because they have excellent courses and professors) I wouldn't even have had the slightest chance to function as a temporary programmer in a company. I tried before. You have no idea how many 'no' answers I got. Meanwhile, a top paid programmer I know who works for one of the best software development companies can only type with two fingers and can't even do a copy paste in Excel! How fair is that?! Yes, what a world. With hard work you get somewhere.. please.
+5 I agree... to some extent. Being a good coder isn't always enough to get a good salary. The best combination is being a good (at least average) coder and having a level a social awareness, and to have the balls on a job interview. My experience is that having balls and being social is more important to have a good salary than being a good coder. Its enough to be an average coder. EDIT: You are angry (and sometimes arrogant), but you are on a better way than a hardcore programmer if want good pay - this is also dependent on the place you work at, but in my experience being a very good coder is secondary most of the time. Debating with anger is also a bad habit. If you got angry you lost the match.
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Excuse me? I come from a university with one of the highest reputations there are. We program and work the qualitative way. This isn't one semester. It's my graduate year. I'm actually going to be an Application Developer. There's only so far you can get with 'practice' and 'experience'. Fundamental concepts and methods are far more important. That's why the top engineers get higher ranked without doing the work. Didn't you ever learn that? The tons of math and logic theory I had to process before I came to this point. The years of lectures on Software Engineering. Never underestimate the importance of scholar theory.
CsTreval wrote:
I come from a university with one of the highest reputations there are
So do I, even if it's from Romania
CsTreval wrote:
I'm actually going to be an Application Developer
So what? I'm a Software Engineer. I don't think it would've got me my job by itself. Being a Software Engineer / Application Developer / Software Architect / [Insert-another-fancy-title-here] counts for nothing in a company that does real work, if you can't back it up with knowledge
CsTreval wrote:
There's only so far you can get with 'practice' and 'experience'
Yes, and after only 2 years experience, I've found my teachers suck, and have nothing to do with the current technologies and methodologies, most of them proven to work (AGILE as a methodology for instance, or HTML5/CSS3 as techonlogies. Not to mention that those who taught Java had no idea on how to use the language besides teaching the fundamental algorithms (sorting, searching) and data structures (arrays, lists) in it)
CsTreval wrote:
The tons of math and logic theory I had to process before I came to this point. The years of lectures on Software Engineering
Oh yeah, the tons of math, logic, and analog electronics :wtf: :wtf: Now, I'm not saying they might not be useful, but the chance they are is pretty negligible. I've been through college too, I even studied pretty hard. Nothing of that ever helped during the first few days of my professional career, while I've banged my head on a wall trying to get Tomcat6 to work on a CentOS. Nothing! Then I've learned that school only teaches you the basics, the rest comes from passion and, most especially, experience. Look at the most prominent guys here (I'm talking OriginalGriff, Dalek Dave, JSOP, and maybe others, who I'm sorry for not mentioning right now). How many of them do you think have strong educational backgrounds? And yet, just look at the stuff this guys post, and the articles they write. That, my friend, comes from experience, and not education. I'll take any of these guys anytime over 90% of my college teachers. Oh, and to end, you know there's an old saying...
Wiser people that you and I said:
Those who can, do. Those who can't, teach
Full-fledged