From the diagram on page 570 of the UML spec I concluded that a Lifeline should have the events property, holding an OrderedSet(OcurrenceSpecification). Unfortunately it is not there, at least in the QVTo implementation that I use.
All I have is the coveredBy property, serving me with an (unordered) Set(InteractionFragment). Since my transformation relies on the correct order of MessageOcurrenceSpecification I somehow need to implement myself what I expected to be implemented by the missing events property.
This is what I have so far:
helper Lifeline::getEvents (): OrderedSet(OccurrenceSpecification) {
return self.coveredBy->selectByKind(OccurrenceSpecification)->sortedBy(true);
}
Obviously sortedBy(true) does not get me far, but I don't know any further. Who can help?
All I could find so far were other people struggling with the same issue years ago, but no solution:
https://www.eclipse.org/forums/index.php/m/1049555/
https://www.eclipse.org/forums/index.php/m/1050025/
https://www.eclipse.org/forums/index.php/m/1095764/
Based on the answer by Vincent combined with input from a colleague of mine I came up with the following solution for QVTo:
-- -----------------------------------------------------------------------------
-- Polyfill for the missing Lifeline::events property
query Lifeline::getEvents (): OrderedSet(OccurrenceSpecification) {
return self.interaction.fragment
->selectByKind(OccurrenceSpecification)
->select(os: OccurrenceSpecification | os.covered->includes(self))
->asOrderedSet();
}
I don't know if it is possible, using directly coveredBy to get an ordered collection. As coveredBy is unordered, if you access it directly by the feature, you will have an unpredictible order and if you try to access it using the eGet(...) stuff, the same result will occur.
However, if I understood correctly, there is a "trick" that could work.
It relies on the assumption that each OccurrenceSpecification instance you need is held by the same Interaction that contains the Lifeline and uses the way EMF stores contained elements. Actually, each contained element is always kind of 'ordered' relatively to its parent (and for each collection so EMF can find elements back when XMI references are expressed using the element position in collections). So, the idea would be to access all the elements contained by the Interaction that owns the lifeline and filter the ones that are contained in coveredBy.
Expression with Acceleo
This is easy to write in MTL/Acceleo. In know you don't use it, but it illustrates what the expression does:
# In Acceleo:
# 'self' is the lifeline instance
self.interaction.eAllContents(OccurrenceSpecification)->select(e | self.coveredBy->includes(e))->asOrderedSet()
with self.interaction we retrieve the Interaction, then we get all the contained elements with eAllContents(...) and we filter the ones that are in the self.coveredBy collection.
But it is way less intuitive in QVT as eAllContents(...) does not exist. Instead you have to gain access to eContents() which is defined on EObject and returns an EList which is transtyped to a Sequence (in QVT,eAllContents() returns a ETreeIterator which is not transtyped by the QVT engine).
So, how to gain access to eContents() in the helper? There is two solutions:
Solution 1: Using the emf.tools library
The emf.tools library give you the ability to use asEObject() which casts your object in a pure EObject and give you more methods to access to (as eClass() for example...etc).
import emf.tools; -- we import the EMF tools library
modeltype UML ...; -- all your metamodel imports and stuffs
...
helper Lifeline::getEvents (): OrderedSet(OccurrenceSpecification) {
return self.interaction.asEObject().eContents()[OccurrenceSpecification]->select(e | self.coveredBy->includes(e))->asOrderedSet();
}
Solution 2: Using oclAstype(...)
If for some reason emf.tools cannot be accessed, you can still cast to an EObject using oclAsType(...).
modeltype UML ...; -- all your metamodel imports and stuffs
modeltype ECORE "strict" uses ecore('http://www.eclipse.org/emf/2002/Ecore'); -- you also register the Ecore metamodel
...
helper Lifeline::getEvents (): OrderedSet(OccurrenceSpecification) {
return self.interaction.oclAsType(EObject).eContents()[OccurrenceSpecification]->select(e | self.coveredBy->includes(e))->asOrderedSet();
}
Limitation
Ok, let's be honest here, this solution seems to work on the quick tests I performed, but I'm not a 100% sure that you will have all the elements you want as this code relies on the strong assumption that every OccurrenceSpecification you need are in the same Interaction as the Liteline instance. If you are sure that all the coveredBy elements you need are in the Interaction (I think they should be), then, that's not the sexiest solution, but it should do the work.
EDIT>
The solution proposed by hielsnoppe is more eleguant than the one I presented here and should be prefered.
You are correct. The Lifeline::events property is clearly shown on the diagram and appears in derived models such as UML.merged.uml.
Unfortunately Eclipse QVTo uses the Ecore projection of the UML metamodel to UML.ecore where unnavigable opposites are pruned. (A recent UML2Ecore enhancement allows the name to be persisted as an EAnnotation.) However once the true property name "events" has been pruned the implicit property name "OccurrenceSpecification" should work.
All associations are navigable in both directions in OCL, so this loss is a bug. (The new Pivot-based Eclipse OCL goes back to the primary UML model in order to avoid UML2Ecore losses. Once Eclipse QVTo migrates to the Pivot OCL you should see the behavior you expected.)
Related
I used the suggested approach in this question to return HATEOAS formatted outputs that match those returned by spring-data-rest. It works good, but is there a way to avoid boiler plate code to create entity resource assemblers like the QuestionResourceAssembler in the referenced question, if I only want to add 'self' links using the id to all entities? Perhaps using ResourceAssemblerSupport?
The easiest way is to simply use the Resource wrapper type:
Resource<Person> personResource = new Resource<>(person);
personResource.addLink(…);
personResource.addLink(…);
Links can be created either by simply instantiating them (i.e. new Link("http://localhost/foo", "relation") or by using the ControllerLinkBuilder which allows you to point to Controller methods for obtain a reverse mapping. See this section of the Readme for details.
With intellij idea, how do I find out what makes a variable be visible?
An example of when it is hard:
Suppose you look at class A, and you see a variable something. If you jump to source you see that it's defined in trait X. But you don't extend trait X directly. What do you extend, then, that makes this variable visible? If you have a deeply nested hierarchy, tracking can be hard.
Any recommendations or solutions?
EDIT: Please vote for the feature if you're interested: http://youtrack.jetbrains.com/issue/IDEA-124369
I don't think that IntelliJ IDEA has any shortcut for "finding what makes a variable visible".
However you can determine it using the "Find Usages" option (Alt + F7). For example:
import java.nio._
object TempObj extends App {
def func = 2
val p = file.Paths.get("some-path")
func
}
So Find Usages on "file", tells you that its from the Package "file" (in heading of the new Tab it also shows the complete package name, ex: Find Usages of java.nio.file in Project Files).
Whereas Find Usages on func will tell you that its a Method (And the Tab heading now says: Find Usages of func() in Project and Libraries)
So now in way you can determine, what exactly makes the variable visible. This also works for imports since it shows the package from which it is imported and you can then look for import of that packages.
I know of two almost-solutions to this problem.
Go-to-declaration, as you mentioned, solves this problem in the case of local variables.
More generally, the "find usages" feature gives you a neat little breakdown by type and file of different uses of the variable. From this you can see if it's involved in a static import.
It's not perfect, but with a moment's thought these two are generally sufficient to figure out what you want.
Use ctrl+b or F4 to jump to source code. Alternatively you can use ctrl+shift+a to get option/action. You can find shortcuts at http://gaerfield.github.io/ide-shortcuts/ as well. Hope it will help.
From what I understood you want to see the code that creates an Object you use, for instance Mystery someMystery;.
That gives you two options to populate someMystery:
someMystery = ... where ... is your code to populate
someMystery and if that is the case you should follow
that code (with ctrl+B as far as you need to) to the point where it
actually creates the Mystery object.
Use CDI to populate that object instance for you, in which case you should look into the CDI mechanism in order to see in what way the object instance is populated.
In either way IMO there is no way to know for sure if the someMystery instance is of some more concrete class than Mystery, because it is decided in runtime, not in compile time, so your next bet would be to run the program in debug and see what object goes into someMystery, although you are not guaranteed to get the same type of object every time.
PS. My answer is based entirely on my java understanding of the topic, can't say if it is valid for scala also.
This might not be exactly the answer you were hoping to get.
However, quoting yourself,
If you have a deeply nested hierarchy, tracking can be hard.
Have you considered using composition over inheritance? Perhaps this would remove the need for the feature you are looking for.
Deeply nested hierarchy doesn't sound good. I understand your pain about that.
When you override vals or defs there is a little circle next to the line number that shows where it is from even when it is from nested hierarchy. Hovering over vals with the command key down also shows you a little tooltip where it is from.
Does this help?
https://youtu.be/r3D9axSlBo8
if you want class, field or method to be visible, you need to implement them as public. If it was your question.
I'm using the #Check annotation in order to validate my dsl. my dsl is for json.
at first the method was invoked for a specific object and once per change
but it suddenly doesn't work in the same way anymore (and i'm not sure what i've done that effected it)
the method signature is:
#Check
public void validateJson(ObjectValue object) {...}
now its entering this method for each node in the gui although i'm editing only one node
The validator works normally in this case. When Xtext re-parses your model, it cannot always avoid re-creating the EMF model that is validated in the Check expression - in other words, the model is practically re-created every time, thus warranting a full validation.
However, in some cases, it is possible that only a partial re-creation of the model is necessary - in these cases it is possible that not all elements are re-validated (however, I am not sure whether this optimization was included).
I'm writing an Eclipse Plugin to do some simple code generation. I'm able to grab an IMethod representing the Method I need to modify, but I'm unsure how to actually write additional code in its body. I know this can be done with AST nodes, so is there a way to convert betwen IMethod and MethodDeclaration or something like that?
IMethod is a class of JDT's Java model while MethodDeclaration is a node class of the JDT AST. The Java model has no connection to the AST. But you can use the model to create an AST, typically ICompilationUnit (represents a Java source file) is used, although creating an AST from a string is also possible.
I would suggest checking out this article
Edit:
Possibly "no direct connection" would have been the better wording. In the JDT FAQ is the following:
How to go from one of IBinding, IJavaElement, ASTNode to another?
[...]
From an IJavaElement to an IBinding
If you only need the binding key and not the binding object itself, look for a 'getKey()' method in a subtype of IJavaElement. This method returns the binding key, which can be useful in many situations e.g. see next point. Note that not all subtypes of IJavaElement have a corresponding binding, e.g. IType and IMethod have one but IPackageFragment and IImportContainer do not.
If you really need the binding objects you can use 'org.eclipse.jdt.core.dom.ASTParser.createBindings(IJavaElement[], IProgressMonitor)'. Note that this operation is slightly expensive, compared to just getting the binding key, as the bindings have to be created.
From an IJavaElement to its declaring ASTNode
org.eclipse.jdt.core.dom.CompilationUnit.findDeclaringNode(String) - The string parameter is the binding key, see previous point.
Having created a standard Silverlight Business Application in VS2010 and set up a model from a SQL Server database, I have various entities and associations, among which AssetGroup and Asset are in a 1:m relationship.
Allegedly I can use dot notation to get the associated AssetGroup out of an asset instance. Through the modern miracles of deferred execution and lazy loading, I am assured, my data will be delivered the very moment that I need it.
But it doesn't work.
What are the required incantations, and do I have to slay a chicken or a goat?
This looks promising. As soon as I've tried it out I'll update.
In the question I mention a blog post containing a possible solution. That solution works, but entails changes to generated code, which is obviously as fragile as a solution gets.
Here's a robust way to apply the solution: change the code generator.
On the EDMX designer surface right-click for the context menu and choose Add Code Generation Items...
Try to improve on "Model1.tt" as a name and save the TT file.
Open the TT file.
Search for "return (" to directly find the method template you need to change.
Edit as shown.
Rebuild the solution.
Change this
return /* big hairy expression */;
to this
var entity = /* big hairy expression */;
if (!entity.IsLoaded) entity.Load();
return entity;