Description Maneesh 2006-06-11 10:26:55 EDT

In two methods of CrossReferenceAdapter, #setTarget and #updateImportsAndExports there is an iterator to iterate over crossreference values of given EObject. This iterator also computes derived features.

Later on in these methods, there is a check to ignore unchangeable feature. The performance is improved a lot by creating an iterator that ignores unchangeable features.

Please use getOptimizedCrossReferenceIterator instead of eCrossReferences().iterator in #setTarget and #updateImportsAndExports


Please see the code below...

    private static Map eClassToChangeableFeatures = new HashMap();
    private static List nullList = new ArrayList(1);
    private static List getCrossReferencesChangeableFeatures(EClass eCls) {
        List features = (List)eClassToChangeableFeatures.get(eCls);
        if(features == null) {
            features = nullList;
            EStructuralFeature [] crossReferenceFeatures = 
                ((EClassImpl.FeatureSubsetSupplier)eCls.getEAllStructuralFeatures()).crossReferences();
            if(crossReferenceFeatures != null) {
                features = new ArrayList(crossReferenceFeatures.length);
                for(int i=0; i<crossReferenceFeatures.length; i++) {
                    EStructuralFeature feature = crossReferenceFeatures[i];
                    if(feature.isChangeable())
                        features.add(feature);
                }
            }
            eClassToChangeableFeatures.put(eCls, features);
        }
        return features != nullList ? features : null;
    }

    private EContentsEList.FeatureIterator getOptimizedCrossReferenceIterator(EObject eObj) {
        List features = getCrossReferencesChangeableFeatures(eObj.eClass());
        if(features != null) {
            EContentsEList list = null;
            if(features.size() > 0) {
                list = new ECrossReferenceEList(eObj, (EStructuralFeature[])features.toArray(new EStructuralFeature[features.size()])) {
                    // to get to the protected constructor
                };
            } else {
                list = ECrossReferenceEList.EMPTY_CROSS_REFERENCE_ELIST;
            }
    
            return (EContentsEList.FeatureIterator) (resolve() ? list.iterator()
                : ((InternalEList) list)
                        .basicIterator());
        }
        return (EContentsEList.FeatureIterator)ECrossReferenceEList.EMPTY_CROSS_REFERENCE_ELIST.iterator();
    }