How to design a UML diagram with a scripting language? - uml

I'm designing a software component which will get instructions from other components on how the UML diagram should look like, and then will produce this UML diagram in different presentation ways (in SVG, GIF, etc.), for example (in Java):
DiagramDesigner designer = new DiagramDesigner();
designer.setStyle('Use Cases')
designer.addActor('User');
designer.addUseCase('Print Document');
// etc.
String svg = designer.getSvg();
I don't want to re-invent the wheel and want to use some industry-standard language/interface for interconnection between my DiagramDesigner and other components. I'm looking for an interface similar to DOM, but for UML, not for XML.
Can anyone help? Thanks in advance.
ps. Besides the example above I would like to make my diagrams inter-operable and transferrable between servers, e.g.:
// first server
String script = designer.getScript();
// second server
DiagramDesigner desiger2 = DiagramDesigner.import(script);

So if I understand you right, you are looking for a way to work with UML on the metamodel level. You should look at the MOF standard and its implementation the EMF (Eclipse Modeling Framework), which is used by almost all Eclipse based UML tools and this framework is used by many other modeling projects, it even somewhat influenced the standardization of MOF (resulting in SMOF and EMOF split) and therefore I would declare it industry standard.

Probably only loosely related but anyhow: PlantUML. It is open source, built in Java and likely contains already parts of what you want to do.

You can inspire from these scripts to generate any output you want:
http://askuml.com/
Currently examples are given in yUML because they're nice but could be anything.

At least for the syntax part, you could get some inspiration from the large set of textual UML tools (theses tools allow designers to textually specify the model and then they automatically show the model graphically using the standard UML notation).
At least of such tools here: http://modeling-languages.com/content/uml-tools#textual

Related

How can I generate a UML diagram without a GUI

I'm trying to create a UML diagram from the command line without preexisting code.
Eventually I'll write code in C++/Java, but I need to create a diagram first.
I'm thinking of a header-like file, which could be read and could generate a diagram.
Of course, I could just create a header and generate it. However, I'm not supposed to write any code until I've submitted my diagram (I'd also just like to have an efficient way to do this for the future).
UML does not require application to draw. On the contrary one of the main usages of UML is to model the application that you're going to build to understand it better and make a better code as a result.
You also don't use application you create to draw UML diagram. You can use any application that supports UML modelling. Simple Google search or visit on Wikipedia will give you tons of options. You may even take a sheet of paper and a pencil. I've seen a course of UML, where participants did not use computers. They were supposed to learn UML, not tools that allow to draw it.
Finally (answering the question stated in the question topic), UML is in no way limited to model only graphical applications. Static structure and dynamic behaviour of the system exists regardless if user communicates with it through a GUI or command line.
Are you sure you understood the reason why you are supposed to make a UML diagram or do you disagree with that reason? What I can definitely suggest is to find a good book about IT business analysis using UML. This site is not to recommend specific books, but again Google will be your friend here.
As according to the comment the goal is to actually generate a UML class diagram from text let me add a second part of answer
First disclaimer. In general SO is not a place to ask for tools and that question is brushing it. Let me make my answer more generic though.
UML is in general graphical language so technically what you need is something that will parse text version of your "diagram" into a nice picture.
Most if not all tools keep UML in some textual format, be it XMI or some internal legacy solution. The problem with that is that the format is usually pretty complex.
There are some tools that are intended to "draw" diagram by typing text and that's probably something that would suit you best. In general I definitely prefer "normal" GUI but if you insist yuml.me has a nice and easy to understand textual layer based on which it generates really cool diagrams. You may expect you will find others as well, so as usually, ask uncle Google. As suggested by Thomas Kilian in a comment, PlantUML is another example as it can work without GUI and "is an open-source tool allowing users to create UML diagrams from a plain text language." (quote after Wikipedia)

Are you modeling or drawing? in uml

Please I need help in understanding this two approaches in the uml world. I am a programmer who is new to uml. I just started learning uml lately but kept getting this phrase asked all the time. - Are you modelling or drawing?. An explanation is needed with clear examples.
This link hinted just a little but I am stil confused -- http://modeling-languages.com/drawing-tools-vs-modeling-tools/
UML is a modeling language, which has a graphical notation. Its semantic is precisely specified by UML 2.5 standard of the OMG and also the international standards ISO 19505-1:2012 and 19505-2:2012 (although the latter corresponds to UML 2.4.1).
THere are two different approaches to UML diagramming. And it's heavily influenced by the tools you use:
Drawing tools generally offer UML shapes to be used in drawings. But there is no deeper meaning behind the shapes. It's only pictures. These tools would allow you to mix a use case with a class or an actor in a deployment diagram. The advantage is that you can do what you want. The inconvenience is that what you want may not be compliant.
Real modeling tools let you combine only valid UML elements together and ensure consistency of what you draw with the deeper meaning of the UML language. And they build a true and comprehensive model behind the scene by combining all the facets of the different diagrams.
Modeling tools can do smarter things. They can relate for example a class to their object instantiations in sequence diagram. They can help you to find all the other models in which a specific class is used. If you rename a class or add a property in one diagram, it'll be automatically reflected in all the others.
Modeling requires more discipline, but it's more powerful in the end. Some modelling tools can even use their understanding of UML to generate code out of the model.
You can use UML diagrams in very free way and you can use them up to the specifications. There are even different UML tools - some support only free style diagrams/drafts, some check dependencies and correctness and thus create models. There are some tools in between (MS Visio is one of them)
Nothing is ideal and fitting for everything. For example, some strict tools (VP and EA) forbid to make number-named classes, but according to UML specification you MUST use number names for anonymous classes. But -sigh- we have what we have.
Use of UML as such is not strictly predefined. So, you can use it for freehand drafts, later work on them more thoroughly and make them models. Or do only drafts. Or only models. But at any moment you should know how strictly are you keeping up to specifications. Or at least, trying to keep up. But even very free draft can help you greatly to understand the task or to think in a more productive way.

Standard UML file format

I have designed UML diagrams in different tools (StarUML, BoUML, Papyrus, Omondo, Rational Rose, etc.) depending on the project and the date (rose was first, after Omondo, then starUMl, ..., now papyrus). However, I see that I cannot open my old UML diagrams because the tool is obsolete.
I would like to know if there is a standard format for UML diagrams. Probably not in production, but at least to know if there is proposal of standard format.
Probably, Eclipse is doing something like that with the M2 project, but do the other tools (not eclipse based) are interested in reading this format.?
Each UML tool uses its own format, but I think the era of proprietary format is over, and open format for diagrams like this should exist.
I have two answers to this:
In theory the standard exchange format for UML models is XMI but it´s true that each vendor implements a slightly different version so interchange is not a reality. Nevertheless, most tools are converging to at least support the Eclipse MDT-UML2 XMI implementation which in my opinion is becoming de facto XMI standard.
The OMG is working on a new standard : Diagram Definition that is supposed to fix the problems with the current XMI one (they are working a lot with many of the top vendors to make sure that this time they all go in the same direction) and, also important, it will allow to interchange not only the data (i.e. the info about the model elements) but also the layout and graphical representation so that after the import you get a model exactly as the same you exported in the first place
Have you heard of XMI?
#JordiCabot here adds some interesting details about it.
Besides Jordi's reference to the Diagram Definition standardization activity, please note that there is another action ongoing from OMG:
a request for comments has been issued in June 2011 for a CANONICAL XMI format, which is basically a subset and a set of additional rules for writing XMI documents that should limit the possibility of creating different XMI dialects, or at least should allow tools to understand a common dialect (the canonical one).

Are UML diagrams the only way to model the software

I often draw a dataflow on a sheet of paper. Even the planning of my little tools is done on a paper.
There exists UML.
The problem is - I don't like it. All the tools I've used (Visio and a lot of online editors) are just not flexible for my hands. With a pencil you can easily draw shapes and connect them, describe them.
What could you suggest in order to create a diagram of data-flow, sequence diagram, etc. in the fastest, most natural and easiest way except on the computer not the paper :)
****Useful links as posted in comments:** SO Link #1 SO Link #2
Right now I am curious about 2 things and one of them was in my minds quite long ago:
1) Mindmap - I've tried a while ago, quite liked it but abandoned. Hoever will give it another try
2) Whiteboard. It would be the easiest and most natural method, except that taking a photo and storing it somewhere on a computer would make the process repetitive and boring.
Has anyone other interesting ideas? I would really like to hear what others are using to design their software and the progress of it.
Thanks a lot!
Why do you want to hand-draw the UML at all whether it's on paper or on the computer?
I agree that you need a model to represent the design. But even in large projects of about 500 man-months, I observed that only 3-4 sequence diagrams really matter and have a chance of surviving the entire lifecycle of the application. Those 3-4 sequence diagrams (and class diagrams that represent their static time relationships), usually represent the high level design of the application.
Or, look at it this way:
Any decent enterprise application will not have 20 different call flows. There will be one or two generic (or abstract) call flows, which all the concrete use cases implement. Let us take a simple Struts / EJB application. The generic flow will be something like - an action class calling a validator and then calling a stateless session bean, which in turn calls a domain class, which will call a DAO. All the use cases of the application just implement this flow with concrete classes that are specific to that use case.
Do you agree?
If you do not, I would like to hear about applications that have 20 different call flows and survived for 5 years after the first release.
If you agree with me, we are boiling down to 3-4 class and sequence diagrams even for large enterprise applications comprising several thousand classes. Why is it a big deal how you draw and maintain those 3-4 diagrams?
You might say that you want to document all the use cases for training or documentation purposes. During my last 14 years of experience in the real enterprise software world, I don’t remember seeing well 'maintained' UML documentation. First of all, good documents are difficult to produce and are not found that often. Secondly, they are out of sync with the code most of the time. Most of my experience is with large banks, insurance companies, Auto companies, etc. Those environments are just too hectic and their resources are limited (really? Are we talking banks? Yes, difficult to believe, but true) for 'maintaining' good documentation.
So am I suggesting that we get rid of UML?
No. We need visual models to represent complex systems. Human brains seem to be at their best when processing visuals. The visual cortex, which is responsible for processing the visual images, is the largest system in the human brain.
So what is a reasonable solution to easily produce and maintain UML models?
Probably we are better off using the current crop of UML tools to draw those 3-4 high-level UML diagrams. If you hate using them, check option 3 below.
For the diagrams at the next level of abstraction (any useful models should have different levels of abstraction), generate the UML from source code. You can generate both class and sequence diagrams.
In this age of agile methodologies, why not just write the shell classes and generate those 3-4 high-level UML class and sequence diagrams as well? This way there won't be any UML to maintain at all.
The source code is the truth.
Can you argue against that statement? If not, why not generate the models from the source code itself? I am not suggesting the round-trip engineering, by the way. I am just suggesting a one way trip - from code to models.
There are 2 main problems however with the generated UML.
When we hand draw a class diagram, we show the relations between the classes involved in a scenario. Most existing class diagram generating tools allow the user to drop the Java classes (the source code) into the tool and the tool automatically shows the relations between the classes. The problem here is, how does one know about the classes involved in a scenario to begin with?
The second problem is the verboseness of the generated diagrams. There are tools available to generate runtime sequence and class diagrams for a scenario. But the diagrams are often very verbose and defeat the purpose of models, whose purpose is to highlight the important aspects and filter out unimportant details.
Good UML generating tools should address both the above problems. There are a few tools in the Java domain that try to address these problems. Check the discussions below:
What tools should I use to visualize structure of my code
Are there any tools for detecting architectural and design patterns in code?
I hope I answered the original question:
Has anyone other interesting ideas? I would really like to hear what others are using to
design their software and the progress of it.
I am the author of the runtime UML generating tool MaintainJ, but I tried to address the original question in an objective manner. Your comments are welcome.
There are various tools that allow you to create diagrams based on textual input. There's some up-front learning in that you need to learn the syntax. However it's not hard to do. Once you have, creating diagrams can be very fast. There are some downsides; in most cases there's limited ability to change the layout/style. Significance of that will depend on whether you like their style or not.
There's a growing number, here's a few you might want to look at:
UMLet: desktop app, supports most UML plus various other diagrams. Can also create your own custom shapes & connectors. FOSS.
WebSequenceDiagrams.com: online sequence diagrams.
TextUML: desktop app. Focus is executable models, auto-generates class diagrams. FOSS. It also has an online commercial sibling.
hth.
I like using a whiteboard and a camera. For even more flexibility, use post-it notes on the whiteboard.
I use ER diagrams (on the whiteboard) to model my data, and message sequence charts (on the whiteboard) to model the data flow. I'll also do quick mockups of UI pages on the whiteboard.
Asides from that, I use Ruby/Rails to code server side and HTML/CSS/jQuery/JS on the client.
If even Visio is not flexible enough, I'd suggest a digital whiteboard or touchscreen with a whiteboard software. After some accommodation you could probably use a simple tablet (without display) as well - they are really cheap.
Regarding pure software: we are trying to achieve a "pen-like" input method with UML Lab, but it currently supports Class Diagrams only...
I think that the UML and code should be mixed using a class diagram. You model your architecture with the class diagram (e.g package, classes etc....) then you code your business finally multiple iterations between code and model.
I think that UML should more be oriented to code but not to focus on textual input.
The problem with standard languages, such as UML, is that you have to invest a considerable effort to learn the language and the modeling tools. These languages are defined by an expert consortium, e.g. OMG, that proposes a language specification suited to the biggest overlap of design problems in a certain domain.
Why not defining your own language that fits exactly to your needs and your specific problem? Such languages are termed Domain-Specific Languages (DSL). Instead of investing into learning a language that's complex, you invest into the definition of a languages that exactly suits your needs.
There are numerous approaches that support the definition of DSLs. The most widespread is the Generic Eclipse Modeling System (GEMS). Personally, I made great experience with GrGen due to its versatility and the possibility to automate working steps using graph transformation.
No. There are various other ways. UML is just an option.
Pen and Paper Prototyping is a great option too, it doesn't have to follow UML.
Mind Map is another great way.
For more adaptive software processes, UML use is encouraged to be as minimum as possible. Such as, teams that practice Agile or XP tend to use UML less and they would rather rely more on informal means to conceptualize the software. In a rigid structured company, UML can be rigorously followed.

Editors to draw diagrams in Unified Modeling Language?

I was wondering how you draw diagrams in Unified Modeling Language for your project design? By hand on paper or some editors on computer? It will be great if there are some convenient editors or other gadgets for help. I am programming under Windows and Ubuntu.
Thanks and regards!
I used Sparx Enterprise Architect.
I reverse the java project and then just drag and drop from the Package Explorer to the diagram. When I have finished to present the existing classes I then add UML classes in the diagram. No code generation or model driven, just UML graphical representation mixing existing classes and abstract classes. I give my diagrams to the team and let them integrate it.
I am very lazy when modeling :-)
(source: forum-omondo.com)
I can see my classes and navigate from one package to another showing associations, inheritances and dependencies dynamically. No need to create a diagram per view, I prefer to use the show hide links and directly navigate in the java code and model from the same diagram it is easier and a lot more powerful because interactive.
(source: forum-omondo.com)
(source: forum-omondo.com)
Just using the class contextual menu I can navigate. Really cool
(source: forum-omondo.com)
I used Poseidon for UML for quite a while.. not that bad, it's just a little bit slow since it's written in Java.
If I remember correctly it also has a community license that can be obtained for free..
I would vote for StarUML
maybe its not brand new, but it does the job!
It works under Windows.
read more about StarUML
I use Dia for my diagramming needs. It's open source and cross platform so you can switch between OS's without worrying about which format your diagrams were in. It exports to several different image types and has a Portable version (for Windows) as well.

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