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Manage multiple models in multiple controllers to keep track on them

I was trying to make a simple application in javafx.
I had 8 views (FXML), so one model for each and same for the controllers.
I had to keep the "context" for each model wherever I was... So I had a function setContext which would take a parameter which is a class that regroup every models.
So in every controllers, I had every models.
But a bit latter, I had to had another page, which would take the result of all those page (questionnaire) and show it, so I could have multiple questionnaire... So I was facing the exact same problem, but I didn't want to do it all over again... Because as soon as I'm creating a new questionnaire, I lose the context of the previous one. I also had to add abstractModel and abstractController for stocking every models. It was ratchet.
So I gave up the idea of one controller for each view.
I ended up with a functionnal application, but with one controller which as over 1000 lines... it's only a questionnaire.
I was wondering if there were any possibilities to do what I attempt to do, with multiple controller, but where I don't need to set the "context"? Like... the pages/views auto-save somehow and won't re-instantiate if I'm not asking for it (like a new questionnaire would reset).
Sush as a static class, like a singleton, but for views and which I'm able to instantiate for every questionnaire. But then again, I keep a track on the old ones.
I'm pretty sure it's possible, but can't find anything about it maybe my formulation of the question is just wrong.
Any ideas? Thanks

Your question is bit abstract and it is hard to give a definitive answer. But you might benefit from introducing a dependency injection framework.
One way to do that would be to use Gluon Ignite: "With this library, developers can use popular dependency injection frameworks in their JavaFX applications, including inside their FXML controllers.". You can choose a dependency injection framework you wish from those supported (for example, Dagger, Guice or Spring). With those systems, you can apply scoping rules to your model classes such as Singleton, for those models for which you only wish to have a single instance for your application. You can also use other scoping rules and producers to create models that have different scopes such as within the context of a wizard or created new every time a form is shown, etc.
Beware that using dependency injection frameworks might make your application a little bit more difficult to understand. Anybody maintaining your application has to additionally learn the dependency injection framework. The framework will create objects and inject references to them into your code automatically and your application might be a bit more difficult to debug due to some seemingly magical generated operations that you don't control. Still, it's a tradeoff and, for medium sized applications, the gain in using dependency injection is probably worth it for a lot of apps. From the description you provided, your application may fall into this class, so you should probably seriously consider this approach.
Note that an alternate to a dependency injection system is a service locator (read about it in the Martin Fowler article on dependency injection that I linked earlier). A sample (extremely basic) version of a service locator would be the vista navigator in this small JavaFX navigation framework, though that doesn't pretend to be a full MVC system.
It's just that I can generate multiple questionnaires, which all have the same models and same views and same controllers. But when I create one, it instantiate everything, but it keeps track on all of them so I can edit them later
You could replace your in-memory structure for keeping track of stuff for editing with a persistent storage, for example a JPA based DB access layer or a NoSQL based DB access layer. One advantage of this could also be that the state of the application would be saved if the application is shut down, then restarted, so the user could just pick up where they left off in their questionnaire.

Is there a MDI/SDI/TDI Framework available for Java Swing?

I am converting an older MDI (Multiple Document Interface in Windows-speak, I don't know what it is called in Java) to Multiple SDI (Single Document interface). It's really "one top window with a menu, owning multiple separate JFrames, each containing their own logic and display". I also plan to have Open/Save workspace. MVC is used as the general architecture.
I have started, and the main idea is to create a bunch of JFrame-derived windows which I keep track of in a Window menu. Models and Controllers of course, but its the View/JFrame that is the main problem. I have already lost myself in a myriad of Action handlers and Window Listeners....
Then it hit me, "this can't be the first time someone writes this". A quick search on Google and SO lead me nowhere. But surely there must exist a framework which does this already? (Preferably in a Model-View-Controller design)
When all I want is to create Models and Controllers, and then implement only the thing that is special for each window/JFrame. The rest (Window management, workspace etc) should be preety standard.
I guess I'm looking for something similar to the App-Wizards/Code-generators in DevStudio.
Does such a framework exist, or am I bound to make one myself?

I know this question is old, just leting here my findings since i had this similar question a while ago.
There is really not such framework/utility out-of-the box, swing really only provides UI controls and components, you have to code youself data binging and validation, also its up to you to handle MDI ( using JInterfalFrames) or SDI (Using a single JFrame and a bunch of jpanels).
As you mentioned, swing does not makes implementing MVC easily, due to all code that may end up inside the *Listeners and *Adapters.
You can make a POC to try out varios swing data-binding frameworks like JGoodies or Project Mogwai, disclamer: haven't used neither.
Optionally if the project allows it, you could try alternative UI frameworks for java like Apache Pivot or JavaFX wich does a better job at separating ui from behaivor.
Sorry for my bad english.

Maintaining Clean Architecture in Spring MVC with a data-centric approach

Maintaining Clean Architecture in Spring MVC with a data-centric approach
I'm trying to map out the architecture for the front-end of a new Java-based web app (portal type application) we are making at work. I want to get this right from day one, and I would like to kick off a discussion here to help me implement Uncle Bob's Clean Architecture in my architectural design.
Here's a quick run-down of our tech stack, top to bottom (the technology isn't importance, the structure is):
Oracle Database
Oracle Service Bus exposing services using WSDLs
JAX-WS generated Java-classes from the WSDLs (let's call this the "generated service layer")
A Domain module consisting of POJOs mapped to the generated data objects
A Consumer-module exposing the "generated service layer" to the front-end application
A Spring MVC based front-end module using FreeMarker to render the views
A key point:
In particular, the name of something declared in an outer circle must not be mentioned by the code in the an inner circle. That includes, functions, classes. variables, or any other named software entity.
Attempting to adhere to Bob's Clean Architecture, I've gone back and forth a bit with myself regarding where to place the application logic, namely the "Use Case"-layer in his architecture.
Here is the approach I've come up with:
Layer 1 - Entities
Entities encapsulate Enterprise wide business rules.
This is where our Domain module containing the domain-objects lives, these are self-containing objects with minimal dependencies on each other. Only logic pertaining to the objects themselves may live on these domain objects, and no use-case specific logic.
Access to our database is exposed via WSDLs using a service bus that transforms the data, as opposed to an ORM like JPA or Hibernate. Because of this, we do not have "entities" in the traditional sense (with Ids), but a data-centric approach making this layer a data access layer, presented to the rest of the application by the Consumer-module.
Layer 2 - Use Cases
The software in this layer contains application specific business rules.
This is where logic specific to our application's use cases lives. Changes to this layer should not affect the data access layer (layer 1). Changes to the GUI or framework implementation (Spring MVC) should not affect this layer.
This is where it gets a little tricky:
Since our data access layer (in layer 1) must be kept clean of application logic, we need a layer that facilitates use of that layer in a fashion that suits the use cases. One solution I've found to this problem is the use a variant of the "MVVM-pattern" that I choose to call MVC-VM. See below for an explanation. The "VM"-part of this lives in this Use Case-layer, represented by *ViewModel-classes that encapsulate this Use Case-specific logic.
Layer 3 - Interface Adapters
The software in this layer is a set of adapters that convert data from the format most convenient for the use cases and entities, to the format most convenient for some external agency such as the Database or the Web.
This is where the MVC-architecture of our GUI lives (the "MVC" in our "MVC-VM"). Essentially this is when the Controller-classes get data from the *ViewModel-classes and puts it in Spring MVC's ModelMap ojects that are used directly by the FreeMarker-templates in the View.
The way I see it, the servicebus would in our case also fall in under this layer.
Layer 4 - Frameworks and Drivers
Generally you don’t write much code in this layer other than glue code that communicates to the next circle inwards.
This layer is really just a configuration-layer in our application, namely the Spring configuration. This would for example be where we specify that FreeMarker is used to render the view.
Model View ViewModel Pattern
MVVM facilitates a clear separation of the development of the graphical user interface (either as markup language or GUI code) from the development of the business logic or back end logic known as the model (also known as the data model to distinguish it from the view model). The view model of MVVM is a value converter meaning that the view model is responsible for exposing the data objects from the model in such a way that those objects are easily managed and consumed.
More on the MVVM-pattern at Wikipedia.
The MVC-VM roles would be fulfilled in our application like so:
Model - represented simply by the ModelMap datastructure in Spring MVC that is used by the view templates.
View - FreeMarker templates
Controller Spring's Controller-classes that directs HTTP URL requests to specific handlers (and as such functions as a FrontController). The handlers in these classes are responsible for fetching data from the use case-layer and pushing it out to the view templates when showing data(HTTP GET), as well as sending data down for storing (HTTP POST). This way it essentially functions as a binder between the ViewModel and View, using the Model.
ViewModel - These classes are responsible for 1) structuring data from the data access layer in a fashion that is usable by the View and 2) treat data-input from the View. "Treat" means to validate and to break down the data so that it can be sent down the stack for storing. This layer would take form as <UseCase>VM-classes in a viewmodel package in our Spring MVC front-end module.
A key component here is the implicit binding that happens in Spring MVC between ModelMap and the FreeMarker-templates. The templates only use the model (ModelMaps), where the controller has put the data in a format it can use. That way we can make templates like so:
<body>
<h1>Welcome ${user}!</h1>
<p>Our latest product:
${latestProduct.name}!
</body>
I apologize for the verbose explanation, but I could not explain this (relatively simple) architecture in fewer words.
I would greatly appreciate some input on my approach here - am I on the right track? Does the MVC-VM thing make sense? Am I violating any Clean Architecture Principles?
There are of course many solutions to this, but I am trying to find a solution that is 1) not over-engineered and 2) adheres to the principles of Bob's Clean Architecture.
Update:
I think the key issue that puts me off here is what form the "Use case" layer takes in this application. Remember we have an MVC front-end that gets data from a data access layer. If the MVC part fits in Bob's "Interfaces adapters", and the domain models of the data layer fit in Bob's "Entities" layer, then what do I call the use case classes that implement application logic? I am tempted to just call them <UseCase>Models and put them in the MVC project, but according to Bob
The models are likely just data structures that are passed from the controllers to the use cases, and then back from the use cases to the presenters and views.
so that means my model objects should be "dumb" (like a simple Map. ModelMap in Spring) and it is then the responsibility of the controller to put data from the Use Case class into this Map-structure.
So again, what form does my Use Case-classes take? How about <UseCase>Interactor?
But in conclusion I realize that the MVC-MV-thing is over-engineering (or simply incorrect) - as "mikalai" indicates below this essentially just a two-layer applcation in its current form; a data access layer and a front-end MVC layer. Simple as that.

Whoa that was a lot. And I think you have mostly translated Uncle Bob's jargon over to your Spring Java app.
Since architecture is mostly opinion and since your question is sort of asking for one...
There are many different styles of architecture and ... most are overrated. Because most are the same thing: higher cohesion and looser coupling through indirection and abstraction.
What matters MOST (IMHO) are the dependencies. Making lots of small projects as opposed to one giant monolithic project is the best way to get "clean" architecture.
Your most important technology for clean architecture will not be "Spring MVC" technology or "Freemarker" templating language, or another Dr. Dobb's article with diagrams of boxes, hexagons and various other abstract polygons.
Focus on your build and dependency management technology. It is because this technology will enforce your architecture rules.
Also if your code is hard to test.. you probably have bad architecture.
Focus on making your code easy to test and write lots of tests.
If you do that it will be easy to change your code with out worry ... so much you could even change your architecture :)
Beware of focusing too much an bull#%$## architecture rules. Seriously: if your code is easy to test, easy to change, easy to understand and performs wells then you have a good architecture. There is no 6 weeks to 6 pack abs article to do this (sorry Uncle Bob). It takes experience and time... there is no magic bullet plan.
So here my own "clean" architecture... I mean guidelines:
Make many small projects
Use dependency management (ie Maven, Gradle)
Refactor constantly
Understand and use some sort of dependency injection (Spring)
Write unit tests
Understand cross cutting concerns (ie when you need AspectJ, metaprogramming, etc..)

My solution
So it turns out that implementing Bob's "Clean Architecture" in Java/Spring MVC is borderline non-trivial and requires more architectural facets than I originally had included.
And I could actually not find any example of implementations online.
Evidently my architecture was missing a separate module for the "Use Case"-layer as this logic should not live in the Spring MVC Web module (and not be called "*ViewModel"). The Web/MVC module is simply a detail of the application, and the application logic should be completely separated from it, and separately testable.
This new "Use Case"-module now contains *Interactor-classes which get data from the domain module (entities). Moreover, "Request/Response Objects" are needed to facilitate the communication between the MVC/Web-module and the Use Case module.
My dependency chain now looks like this:
Spring MVC module -> Use Case module -> Domain module
where every arrow (dependency) takes form as a Boundary, meaning an interface is defined in the module to the right of the arrow that is implemented where required and injected where needed (Inversion of Control).
Here are the interfaces I ended up with (per Use Case):
I<UseCase>Request - implemented in the MVC module, instantiated in the Controller
I<UseCase>Response - implemented in the Use Case module, instantiated in the Interactor
I<UseCase>Interactor - implemented in the UseCase module, injected in the Controller
I<UseCase>Consumer - implemented in the Domain module, injected in the Interactor
How it works?
The Controller takes parameters from the HTTP request and packs it in a RequestModel which it passes down to the Interactor. The Interactor fetches the data it needs from the domain module *Consumer and imposes it's application specific logic on it, then puts it in a ResponseModel and sends it back up to the Controller. The Controller then finally simply puts this (now GUI-friendly) simple data in a Map object and forwards it to the FreeMarker template which then uses this data directly and renders the HTML.
A Presenter could get involved in that last part there, making this an implementation of the Model-View-Presenter pattern, but I'm leaving that for now.
My conclusion
I ended up with more files than what is necessary this early in development, strictly speaking. However as the complexity and size of the application grows, I am confident that this structure keeps it easy for us to maintain low coupling and high cohesion. Also, the Web-module is now easily replaceable - it just delivers requests to the use-case module and receives response-objects. Moreover, each layer of the application (domain logic, application logic, and GUI logic) is separately testable, with only the View-part requiring a webserver in order to be tested.
Thanks for all advice and pointers I received here. And please comment on my solution - I don't claim that it is perfect.

Because of this, we do not have "entities" in the traditional sense
(with Ids), but a data-centric approach making this layer a data
access layer, presented to the rest of the application by the
Consumer-module.
Something seems odd to me in that part. Why couldn't your entities have ID's even if you get them from web services ?
In the Clean Architecture approach, the Entities layer is precisely not a data access layer. Data access should be a detail in your architecture, not a central concern. As you said yourself, Entities contain domain-specific business rules. Business rules, or behavior, is very different from the way you fetch your data.
Entities is where all the domain logic happens, not where you get your data from. According to Clean Architecture, you get your persisted or external data from Gateways.
One solution I've found to this problem is the use a variant of the
"MVVM-pattern" that I choose to call MVC-VM. See below for an
explanation. The "VM"-part of this lives in this Use Case-layer,
represented by *ViewModel-classes that encapsulate this Use
Case-specific logic.
ViewModel clearly refers to a View, which is a presentation artifact -another detail. Use cases/Interactors should be devoid of such details. Instead, Interactors should send and receive delivery mechanism-agnostic data structures (RequestModels and ResponseModels) through Boundaries.
I understand that this is a custom pattern of yours and doesn't involve a reference to a presentation framework, but the word "View" is just misleading.

How to organize controllers/presenters in a large JavaFx 2.0 application?

For a project I've been working on a JavaFX 2.0 desktop application (a keytool UI). The way JavaFx2.0 works (in my project anyways), the UI event handling takes place in the JavaFX 2.0 UI classes itself (for example: onclicked() events or property change listeners).
Right now I use a static class with a method: getController(), which all UI classes use to access the one controller of the application (somehow it seemed messy to me to pass the controller on to all 50+ UI classes).
The problem is however that that one controller is getting very large! It has way too many methods (all business logic methods that need to be accessed by my UI classes). Even though it only passes the methods calls on to my model/service, there is still a lot of exceptions that need to be caught on controller level for handling them in the UI (show error messages etc).
Anyone know of a clean way to make this whole MVC/MVP pattern work better for my application without the UI / Controller / Model classes being directly depending on eachother? Maybe a different controller for each use case? But then how would I make it so that the right UI class gets the right Controller without directly knowing it? Maybe using an interface?

I don't really know Java FX, so you should take my answer with a grain of salt. I looked a bit at Java FX tutorials, but they all seem to be tiny examples with no architecture of any kind... MVC or other.
Maybe you should not try too hard to have a clean MVC pattern. It seems to me that each UI element is itself a MVC unit, e.g. a Label contains text (the model), its graphical representation (the view) and it handles events (the controller).
You might just be making your life more painful by trying to have a separate global controller.
You might however keep a separate model, which would be necessary for example if you are showing the content of a database (the model). However if you are doing something quite simple, just using the state of the UI as your model would be sufficient; keeping the data (model) separately in the program would just make you waste time synchronizing the data in the UI's and the data in the separate model. Data duplication is evil and should be avoided as much as possible.

I propose you to test the JRebirth Framework
It provide a simple but powerful pattern which will help you to structure your application.
This framework is young and will be improved according to feedback received. Don't hesitate to send some.
http://www.jrebirth.org/doc/Overview.html
Check the overview page and source code provided to learn more.
Live Demo are also available

There is a series of blogs here Building JEE applications in JavaFX 2.0 that may help you. It presents several patterns with example on how to decouple the different components (MVP) in an JavaFx2 application.

I have put a basic tutorial on my website for a while ago on how MVC pattern can be implemented using Java and Javafx 2. The model class is always decoupled and shouldn't know anything about the controller and viewer. If this is a large project I would recommend using modules where you have your model, viewer and controller in there. A module could be admin portal or google map viewer etc.
http://www.pergande.net/blog/article/post/Javafx+2.0+MVC/id/1

Looking for design patterns to isolate framework layers from each other

I'm wondering if anyone has any experience in "isolating" framework objects from each other (Spring, Hibernate, Struts). I'm beginning to see design "problems" where an object from one framework gets used in another object from a different framework. My fear is we're creating tightly coupled objects.
For instance, I have an application where we have a DynaActionForm with several attributes...one of which is a POJO generated by the Hibernate Tools. This POJO gets used everywhere...the JSP populates data to it, the Struts Action sends it down to a Service Layer, the DAO will persist it...ack!
Now, imagine that someone decides to do a little refactoring on that POJO...so that means the JSP, Action, Service, DAO all needs to be updated...which is kind of painful...There has got to be a better way?!
There's a book called Core J2EE Patterns: Best Practices and Design Strategies (2nd Edition)...is this worth a look? I don't believe it touches on any specific frameworks, but it looks like it might give some insight on how to properly layer the application...
Thanks!

For instance, I have an application where we have a DynaActionForm with several attributes...one of which is a POJO generated by the Hibernate Tools. This POJO gets used everywhere...the JSP populates data to it, the Struts Action sends it down to a Service Layer, the DAO will persist it...ack!
To me, there is nothing wrong with having Domain Objects as a "transveral" layer in a web application (after all, you want their state to go from the database to the UI and I don't see the need to map them into intermediate structures):
Now, imagine that someone decides to do a little refactoring on that POJO...so that means the JSP, Action, Service, DAO all needs to be updated...which is kind of painful...There has got to be a better way?!
Sure, you could read "Beans" from the database at the DAO layer level, map them into "Domain Objects" at the service layer and map the Domain Objects into "Value Objects" for the presentation layer and you would have very low coupling. But then you'll realize that:
Adding a column in a database usually means adding some information on the view and vice-versa.
Duplication of objects and mappings are extremely painful to do and to maintain.
And you'll forget this idea.
There's a book called Core J2EE Patterns: Best Practices and Design Strategies (2nd Edition)...is this worth a look? I don't believe it touches on any specific frameworks, but it looks like it might give some insight on how to properly layer the application...
This book was a "showcase" of how to implement (over engineered) applications using the whole J2EE stack (with EJB 2.x) and has somehow always been considered as too complicated (too much patterns). On top of that, it is today clearly outdated. So it is interesting but must be taken with a giant grain of salt.
In other words, I wouldn't recommend that book (at least certainly not as state of the art). Instead, have a look at Real World Java EE Patterns - Rethinking Best Practices (see Chapter 3 - Mapping of the Core J2EE patterns into Java EE) and/or the Spring literature if you are not using Java EE.

First, avoid Struts 1. Having to extend a framework class (like DynaActionForm) is one of the reasons this framework is no longer a good choice.
You don't use spring classes in the usual scenarios. Spring is non-invasive - it just wires your objects. You depend on it only if using some interfaces like ApplicationContextAware, or if you are using the hibernate or jdbc extensions. Using these extensions together with hibernate/jdbc completely fine and it is not an undesired coupling.
Update: If you are forced to work with Struts 1 (honestly, try negotiating for Struts 2, Struts 1 is obsolete!), the usual way to go was to create a copy of the Form class, that contained the exact same fields, but did not extend the framework class. There would be a factory method that takes the form class and returns the simple POJO. This is duplication of code, but I've seen it in practice and is not that bad (compared to the use of Struts 1 :) )

I think your problem is not so big as it seems.
Let's imagine, what can you really change in your POJO:
1) name of its class: any IDE with refactoring support will automatically make all necessary changes for you
2) add some field/method: it almost always means adding new functionality what is always should be done manually and carefully. It usually cause to some changes in your service layer, very seldom in DAO, and usually in your view (jsp).
3) change methods implementation: with good design this should cause any changes in other classes.
That's all, imho.
Make a decision about technology for implementing busyness-logic (EJB or Spring) and use its facilities of dependency injection. Using DI will make different parts of your program communicate to each other through interfaces. It should be enough for reaching necessary (small enough) level of coupling.

It's always nice to keep things clear if you can and separate the layers etc. But don't go overboard. I've seen systems where the developers were so intent on strictly adhering to their adopted patterns and practices that they ended up with a system worse than the imaginary one they were trying to avoid.
The art of good design is understanding the good practices and patterns, knowing when and how to apply them, but also knowing when it's appropriate to break or ignore them.
So take a good look at how you can achieve what you are after, read up on the patterns. Then do a trial on a separate proof of concept or a small part of your system to see your ideas in practice. My experience is that only once you actually put some code in place, do you really see the pros and cons of the idea. Once you have done that, you will be able to make an informed decision about what you will or will not introduce.
Finally, it's possible to build a system which does handle all the issues you are concerned about, but be pragmatic - is each goal you are attempting to reach worth the extra code and APIs you will have to introduce to reach it.

I'd say that Core J2EE Patterns: Best Practices and Design Strategies (2nd Edition) addresses EJB 2.0 concerns, some of which would be considered anti-patterns today. Knowledge is never wasted, but I wouldn't make this my first choice.
The problem is that it's impossible to decouple all the layers. Refactoring the POJO means modifying the problem you're solving, so all the layers DO have to be modified. There's no way around that.
Pure decoupling of layers that have no knowledge of each other requires a lot of duplication, translation, and mapping to occur. Don't fall for the idea that loose coupling means this work goes away.
One thing you can do is have a service layer that's expressed in terms of XML requests and responses. It forces you to map the XML to objects on the service side, but it does decouple the UI from the rest.