public FeatureDiffReaderImpl getDifferences(
String fromVersion, String toVersion, Filter filter, String[] userIds) throws IOException {
if (filter == null) filter = Filter.INCLUDE;
RevisionInfo r1 = new RevisionInfo(fromVersion);
RevisionInfo r2 = new RevisionInfo(toVersion);
// gather modified ids
ModifiedFeatureIds mfids =
store.getModifiedFeatureFIDs(
schema.getTypeName(), fromVersion, toVersion, filter, userIds, getTransaction());
// build all the filters to gather created, deleted and modified features at the appropriate
// revisions, depending also on wheter creation/deletion should be swapped or not
FilterFactory ff = CommonFactoryFinder.getFilterFactory(null);
VersionedFIDMapper mapper = (VersionedFIDMapper) store.getFIDMapper(schema.getTypeName());
return new FeatureDiffReaderImpl(store, getTransaction(), schema, r1, r2, mapper, mfids);
}
