debugging java implementation of Fame ... - Moose-dev

13 Dec 2010

Hi all,

I need some help with the Java implementation of Fame.

I am trying to implement separate parsing in VerveineJ so that one can
deal with larger project by parsing them piece by piece.
This implies loading in verveine the MSE already created to be able to
add new entities to it.

And The import method of Repository does not work for big MSE files
(that were generated by the export method of Repository BTW) :-(

It crashes with a StackOverflow:
Exception in thread "main" java.lang.StackOverflowError
	at java.util.HashMap.put(HashMap.java:389)
	at java.util.HashMap.putAll(HashMap.java:541)
	at ch.akuhn.fame.fm3.MetaDescription.collectAllAttributes(MetaDescription.java:192)
	at ch.akuhn.fame.fm3.MetaDescription.collectAllAttributes(MetaDescription.java:191)
	at ch.akuhn.fame.fm3.MetaDescription.collectAllAttributes(MetaDescription.java:191)
	at ch.akuhn.fame.fm3.MetaDescription.collectAllAttributes(MetaDescription.java:191)
	at ch.akuhn.fame.fm3.MetaDescription.collectAllAttributes(MetaDescription.java:191)
	at ch.akuhn.fame.fm3.MetaDescription.collectAllAttributes(MetaDescription.java:191)
	at ch.akuhn.fame.fm3.MetaDescription.allAttributes(MetaDescription.java:139)
	at ch.akuhn.fame.Repository.add(Repository.java:121)
	at ch.akuhn.fame.Repository.add(Repository.java:131)
	at ch.akuhn.fame.Repository.add(Repository.java:131)
+ zillions of this same line, Repository.add calling itself
recursively at line 131

I looked a bit into it and think that the problem may come from line
131 into the Repository.add() method :-)

    public void add(Object element) {
        assert element != null;
        if (elements.add(element)) {
            MetaDescription meta = metamodel.getDescription(element.getClass());
            assert meta != null : element.getClass();
            for (PropertyDescription property : meta.allAttributes())
{   <--- line 121
                if (!property.isPrimitive()) {
                    boolean isRoot = property.getType().isRoot();
                    for (Object value : property.readAll(element)) {
                        assert value != null : property.getFullname();
                        if (!(isRoot &&
                                (value instanceof String ||
                                value instanceof Boolean ||
                                value instanceof Number))) {
                            try {
                                this.add(value);
                              <--- line 131
                            } catch (ClassNotMetadescribedException e) {
                                throw new
ElementInPropertyNotMetadescribed(property);
                            }
                        }
                    }
                }
            }
        }
    }

My suspicion is that this recursive call is actually walking through
the entire graph of FamixEntities because every entity is related to
some other entity ...

1- Anybody want to comment on this suspicion?
2- Any idea how to correct it?

nicolas

-- 
Nicolas Anquetil        Univ. Lille1 / INRIA-equipe RMod