After doing some debugging, here is what I think is the problem:
In the ExpansionTerms.java file, line 82
github line 82
: the object te of class EntryStatistics is always assigned a value of null. Thus the if statement in the next line(83) is never evaluated to true and therefore the originalTermids don't get assigned any value.
Now the reason that the EntryStatistics object has a null value is because when the properties of a term is initialized at line 337 ( github line 337
) of MatchingQueryTerms.java with the QueryTermProperties constructors in lines 92-95 ( github line 92
) of MatchingQueryTerms.java, it doesn't assign any value to the stats variable. Therefore, it will have a value of null by default.
If you think this is a bug, what would you suggest to resolve it?
Many thanks for your time!