Java - UML

[Elias Gomersen]

Hello coders!
I have a re-exam tomorrow about UML. The tasks will be about translating text with requirements into UML and then code based on the UML. I have not understood the UML very well. I am wondering if someone could link me good website to learn about UML and translating UML To code?

thanks in advance

[Daniel Demesmaecker]

uml tutorial

[Elias Gomersen]

Daniel Demesmaecker wrote:uml tutorial

It will be about UML class diagrams. I need something more in details and information with code examples.

[Daniel Demesmaecker]

Of has code examples

[Daniel Demesmaecker]

Ever tried Google? Or any searchengine for that mather?

[Elias Gomersen]

Daniel Demesmaecker wrote:Ever tried Google? Or any searchengine for that mather?

Yeah I have. Have not found solid website, that's why I asked on this forum, if someone knows something really understandable and easy.

[Daniel Demesmaecker]

Im almost home. I'll check then. Its a bit easier then  on my phone while on the road

[Daniel Demesmaecker]

I'll make a sketch with some explanation myself

[Campbell Ritchie]

Daniel Demesmaecker wrote:uml tutorial

I only had a few minutes' look at that link, but I thought it looked good.

[Daniel Demesmaecker]

Campbell Ritchie wrote:

Daniel Demesmaecker wrote:uml tutorial

I only had a few minutes' look at that link, but I thought it looked good.

So did I, so sorry to disapoint you but I'm not gonna waiste my time with writting my own examples, everything you need to know is in there and there are clear examples for the different kind of diagrams.
I'm all for helping, but the op (you) should at least make some effort.

[Daniel Demesmaecker]

If you have any specific questions I'm happy to answer them for you, but trying to explain uml's as a whole is a bit mutch, especially since I don't know what your experience is.
You say you have a re-exam tommorow. There are two thing that bug me about this, first of all, you already failled once (that's not what bugs me, building up to it) and your exam is tommorow.
If you already failled once you really shouldn't wait till the evening before the exam to go on a forum and say I don't understand explain it to me or find me a tutorial.
After you failled your exam, you could have talked to your professor and asked for feedback/additional information or looked for other rss

[Tim Holloway]

It may already be "tomorrow" where you are, and in any event, what I'm suggesting shouldn't be done when you have a deadline, but in the longer term this may help.

There's an open-source GUI UML design tool called ArgoUML. It can be downloaded and run via Java's jnlp. It's actually a standard Java application.

You can use this to create your own UML diagrams, and it does have some ability to do "round trip" engineering by being able to create some UML diagrams by reading program code.

Having said all that, I feel obliged, however, to point out that outside of your immediate scholastic needs that UML hasn't proven to be the "silver bullet" that everyone expected and I don't think it's actually that popular in daily design in most shops.

UML is good for abstract analysis and design. You'll probably see lots of it in books on design patterns. But it is fairly abstract, and just as there's really no way to take a design pattern (which is also an abstract thing) and automatically generate functional code without any programming skills, it's really not possible to create a functional program mindlessly from UML. I could cite you a very large company or 2 in my town that had to learn that the hard way. There were cubicles covered with UML wallpaper and people working for months and months creating stick-figure diagrams and when their deadlines approached, it was all panic and fallback to more traditional tools.

I'm very happy that there are readily-available UML resources without the horrendous expense that came with Rational. But for me, it's another tool in the toolbox. One of the worst offences of UML is that if you turn it loose on a large system, it has no priorities and you end up with acres of diagrams, many of which are too trivial to be worth looking at, but they appear just as prominent as the more critical ones. So good luck, but don't spend a lot of time worrying about being a UML expert above and beyond what it takes to pass the course. I don't think I've seen UML listed as a must-have skill on a job advertisement since about 2003.

[salvin francis]

Daniel Demesmaecker wrote:I'll make a sketch with some explanation myself

The above commitment you gave contradicts with the post below (I have read Campbell's post too, but I feel that an outright denial is rude) :

Daniel Demesmaecker wrote:So did I, so sorry to disapoint you but I'm not gonna waiste my time with writting my own examples, everything you need to know is in there ...

Here's a quote from FirstRuleDoNoHarm

FirstRuleDoNoHarm wrote:...If you're in a hurry and don't have the time to do these things or find yourself becoming impatient with the original poster, don't post an answer. ...
If the question is unclear, ask the questioner to clarify without sounding rude. This will help them find out what exactly they are asking, as this sometimes is a big challenge.  

Hope you take my criticism positively.

[Daniel Demesmaecker]

salvin francis wrote:
The above commitment you gave contradicts with the post below (I have read Campbell's post too, but I feel that an outright denial is rude)

I agree with you it contradicts, I was planning on writting an example, cause the op wasn't satisfied with the link I posted, but afterwards I had a better look at the tutorial and felt like it was clear enough

FirstRuleDoNoHarm wrote:...If you're in a hurry and don't have the time to do these things or find yourself becoming impatient with the original poster, don't post an answer. ...
If the question is unclear, ask the questioner to clarify without sounding rude. This will help them find out what exactly they are asking, as this sometimes is a big challenge.  

I did tell the op if he had any specific questions I would be happy to answer them, but I can only repeat myself and say there should be at least some effort on their part...
Have you seen the tutorial I posted? I doubt I could have written it any clearer myself

[Daniel Demesmaecker]

But just to make it a bit easier on the op...

Class UML diagram is the most common diagram type for software documentation. Since most software being created nowadays is still based on the Object-Oriented Programming paradigm, using class diagrams to document the software turns out to be a common-sense solution. This happens because OOP is based on classes and the relations between them.

In a nutshell, class diagrams contain classes, alongside with their attributes (also referred to as data fields) and their behaviors (also referred to as member functions). More specifically, each class has 3 fields: the class name at the top, the class attributes right below the name, the class operations/behaviors at the bottom. The relation between different classes (represented by a connecting line), makes up a class diagram.

The example above shows a basic class diagram. The ‘Checkings Account’ class and the ‘Savings Account’ class both inherit from the more general class, ‘Account’. The inheritance is shown using the blank-headed arrow. The other class in the diagram is the ‘Client’ class. The diagram is quite self-explanatory and it clearly shows the different classes and how they are interrelated.
Object Diagram

When we discuss structural UML diagrams, we have no choice but to delve deeper into computer science-related concepts. In software development, Classes are considered abstract data types, whereas objects are instances of the abstract class. For example, if we have a class “Car” which is a generic abstract type, then an instance of the class “Car” would be an “Audi”.

Object UML diagrams help software developers check whether the generic abstract structure that they have created (class diagram), represents a viable structure when put into practice, i.e: when the objects of a class are instantiated. Some developers see it as a secondary level of accuracy checking.

The object UML diagram above is based on the class diagram we showed earlier. It depicts instances (objects) of the classes we created earlier. To be more precise, the general class ‘Client’, now has an actual client called “James”. James is an instance of the more generic class and it has the same attributes, however with given values. The same thing has been done with the Checkings and Savings account. They are both objects of their respective classes.

Do you notice any mistake? Take a look at the class diagram example. You can notice that the attributes ‘account_number’ and ‘routing_number’ are different for the Checkings and Savings account. As a result, it makes more sense to put those attributes in their respective classes, rather than in the more generic class ‘Account’.

Additionally, we notice that we do not use the attributes ‘wire_routing_number’ and ‘bic’. This is an indicator that something could be wrong in the design of our system. Perhaps we don’t require them in this specific example, thus allowing us to keep the old structure. However, there is a good chance that there is a design flaw which must be resolved immediately.

[salvin francis]

Thank you for taking my criticism positively. Your quality post will not just benefit OP but any other user searching for a similar topic in the future.
+ cow for your effort.

[Campbell Ritchie]

Daniel Demesmaecker wrote:. . . Do you notice any mistake? Take a look at the class diagram example. You can notice that the attributes ‘account_number’ and ‘routing_number’ are different for the Checkings and Savings account. As a result, it makes more sense to put those attributes in their respective classes, rather than in the more generic class ‘Account’. . . .

But all Accounts have an account number, so maybe it woud be better to have that field in the generic and maybe abstract Account class. In which case it would be a bad idea for the subclasses to have a number field, too. The same would apply to BIC etc., which are presumably analogous to what I know as the sort code.

[Harry Kar]

Dunno when is "tommorow" for you(by the way agree with Tim's H. post) but can be useful to you maybe for the next time or for who stump upon that thread:
http://www.nyu.edu/classes/jcf/g22.2440-001_sp09/handouts/UMLBasics.pdf (contains some useful resources too).
and about FOSS UML tools
the search page for more insight