We are attempting to perform a filtered search on two indices joined by a MultiSearcher. Unfortunately, it appears there is an issue in the lucene code that is causing the filter to be simply reused at the starting ordinal for each individual index instead of being augmented by the starting document identifier. We are hoping there is an alternate API that will allow us to perform a filtered search on multiple indices.
For example, we have two indices with three documents each, and a filter containing only doc ID 1. When we perform a filtered search on a MultiSearcher that joins these two indices, we get two documents back (1, 4), where we were expecting only the one. This is because the MultiSearcher, instead of starting at doc ID 3 for the second index, is interpreting the filter individually for each index. We are using Lucene 3.0.2. The API we see this behavior with is MultiSearcher.search(Query, Filter, nDocs) with a MatchAllDocsQuery and the filter code pasted below: public class OpenBitSetFilter extends Filter { private OpenBitSet openBitSet; public OpenBitSetFilter(OpenBitSet openBitSet) { this.openBitSet = openBitSet; } public DocIdSet getDocIdSet(IndexReader indexReader) throws IOException { return openBitSet; } }