sorting xtext AST through quickfix - eclipse

Question

I've Been Trying to change the order of nodes through quickfix, but something is wrong.
Here's my code in xtend:
#Fix(org.xtext.custom.conventions.validation.ConventionsValidator::CONVENTION_NOT_ORDERED)
def fixFeatureName( Issue issue, IssueResolutionAcceptor acceptor){
acceptor.accept(issue, 'Sort', "Sort '" + issue.data.head + "'", null)[
element, context |
var gr=(element as Greeting)
if (gr.name === null || gr.name.length === 0)
return;
var econt=gr.eContainer.eContents
var comparator = [ EObject obj1, EObject obj2 |
var o1 = (obj1 as Greeting)
var o2 = (obj2 as Greeting)
return o1.name.compareTo(o2.name)
]
ECollections::sort(econt, comparator)
]
}
No exception is being thrown to console, in debug I found an UnsupportedOperationException is thrown and handled by xtext.
I suspect that EList is immutable.
So how can I sort the AST?
(Here is the generated code: )
#Fix(ConventionsValidator.CONVENTION_NOT_ORDERED)
public void fixFeatureName(final Issue issue, final IssueResolutionAcceptor acceptor) {
String[] _data = issue.getData();
String _head = IterableExtensions.<String>head(((Iterable<String>)Conversions.doWrapArray(_data)));
String _plus = ("Sort \'" + _head);
String _plus_1 = (_plus + "\'");
final ISemanticModification _function = new ISemanticModification() {
public void apply(final EObject element, final IModificationContext context) throws Exception {
Greeting gr = ((Greeting) element);
boolean _or = false;
String _name = gr.getName();
boolean _tripleEquals = (_name == null);
if (_tripleEquals) {
_or = true;
} else {
String _name_1 = gr.getName();
int _length = _name_1.length();
boolean _tripleEquals_1 = (Integer.valueOf(_length) == Integer.valueOf(0));
_or = (_tripleEquals || _tripleEquals_1);
}
if (_or) {
return;
}
EObject _eContainer = gr.eContainer();
EList<EObject> econt = _eContainer.eContents();
final Function2<EObject,EObject,Integer> _function = new Function2<EObject,EObject,Integer>() {
public Integer apply(final EObject obj1, final EObject obj2) {
Greeting o1 = ((Greeting) obj1);
Greeting o2 = ((Greeting) obj2);
String _name = o1.getName();
String _name_1 = o2.getName();
return _name.compareTo(_name_1);
}
};
Function2<EObject,EObject,Integer> comparator = _function;
final Function2<EObject,EObject,Integer> _converted_comparator = (Function2<EObject,EObject,Integer>)comparator;
ECollections.<EObject>sort(econt, new Comparator<EObject>() {
public int compare(EObject o1,EObject o2) {
return _converted_comparator.apply(o1,o2);
}
});
}
};
acceptor.accept(issue, "Sort", _plus_1, null, _function);
}
thanks!

Answer 1

Sorting a temporary collection which will then replace econt didn't work. but I managed to solve it in a different way.
so one solution was to force a cast of eContainer as it's runtime element (which is Model), and then getting a list with it's getGreetings getter, and with that element the sorting works, but I didn't want to involve non-generic code, for technical reasons.
So after a lot of experiments I finally found that element without involving any other elements or keywords from the grammar:
var econt = (gr.eContainer.eGet(gr.eContainingFeature) as EObjectContainmentEList<Greeting>)
and that is exactly what was looking for. Sorting is successful!
Here's the resulting Xtend code (got rid of casing in the comperator as well):
#Fix(ConventionsValidator::CONVENTION_NOT_ORDERED)
def fixFeatureName(Issue issue, IssueResolutionAcceptor acceptor) {
acceptor.accept(issue, 'Sort', "Sort '" + issue.data.head + "'", null) [
element, context |
var gr = (element as Greeting)
if (gr.name === null || gr.name.length === 0)
return;
var econt = (gr.eContainer.eGet(gr.eContainingFeature) as EObjectContainmentEList<Greeting>)
var comparator = [ Greeting o1, Greeting o2 |
return o1.name.compareTo(o2.name)
]
ECollections::sort(econt, comparator)
]
}
and the generated java:
#Fix(ConventionsValidator.CONVENTION_NOT_ORDERED)
public void fixFeatureName(final Issue issue, final IssueResolutionAcceptor acceptor) {
String[] _data = issue.getData();
String _head = IterableExtensions.<String>head(((Iterable<String>)Conversions.doWrapArray(_data)));
String _plus = ("Sort \'" + _head);
String _plus_1 = (_plus + "\'");
final ISemanticModification _function = new ISemanticModification() {
public void apply(final EObject element, final IModificationContext context) throws Exception {
Greeting gr = ((Greeting) element);
boolean _or = false;
String _name = gr.getName();
boolean _tripleEquals = (_name == null);
if (_tripleEquals) {
_or = true;
} else {
String _name_1 = gr.getName();
int _length = _name_1.length();
boolean _tripleEquals_1 = (Integer.valueOf(_length) == Integer.valueOf(0));
_or = (_tripleEquals || _tripleEquals_1);
}
if (_or) {
return;
}
EObject _eContainer = gr.eContainer();
EStructuralFeature _eContainingFeature = gr.eContainingFeature();
Object _eGet = _eContainer.eGet(_eContainingFeature);
EObjectContainmentEList<Greeting> econt = ((EObjectContainmentEList<Greeting>) _eGet);
final Function2<Greeting,Greeting,Integer> _function = new Function2<Greeting,Greeting,Integer>() {
public Integer apply(final Greeting o1, final Greeting o2) {
String _name = o1.getName();
String _name_1 = o2.getName();
return _name.compareTo(_name_1);
}
};
Function2<Greeting,Greeting,Integer> comparator = _function;
final Function2<Greeting,Greeting,Integer> _converted_comparator = (Function2<Greeting,Greeting,Integer>)comparator;
ECollections.<Greeting>sort(econt, new Comparator<Greeting>() {
public int compare(Greeting o1,Greeting o2) {
return _converted_comparator.apply(o1,o2);
}
});
}
};
acceptor.accept(issue, "Sort", _plus_1, null, _function);
}