void AddToResult(SearchResult result, Postings found)
{
foreach (Posting posting in found)
{
result.Add(new SearchHit(posting.Record));
}
}
void SearchToken(SearchResult result, Token token)
{
Postings postings = (Postings)_postings[token.Value];
if (null != postings)
{
AddToResult(result, postings);
}
}
SearchResult IncludeAll(ITokenizer tokenizer, Token token)
{
ArrayList results = new ArrayList();
while (null != token)
{
SearchResult tokenResult = new SearchResult();
SearchToken(tokenResult, token);
results.Add(tokenResult);
token = tokenizer.NextToken();
}
SearchResult result = (SearchResult)results[0];
for (int i=1; i<results.Count && result.Count > 0; ++i)
{
result = result.Intersect((SearchResult)results[i]);
}
return result;
}
SearchResult IncludeAny(ITokenizer tokenizer, Token token)
{
SearchResult result = new SearchResult();
while (null != token)
{
SearchToken(result, token);
token = tokenizer.NextToken();
}
return result;
}
/// <summary>
/// Build a new SearchResult object including
/// only those elements for which the
/// filter returns true.
/// </summary>
/// <param name="filter">filter</param>
/// <returns>a new SearchResult containing all the elements for which
/// <see cref="ISearchHitFilter.Test"/> returned true</returns>
public SearchResult Filter(ISearchHitFilter filter)
{
SearchResult result = new SearchResult();
foreach (SearchHit hit in _hits)
{
if (filter.Test(hit))
{
result.Add(hit);
}
}
return result;
}
/// <summary>
/// Set intersection operation. Creates
/// a new SearchResult with all the records
/// that exist in both SearchResult objects.
/// </summary>
/// <param name="other"></param>
/// <returns>a SearchResult representing the
/// intersection between the this and other objects
/// </returns>
/// <remarks>all the SearchHit objects in
/// the resulting SearchResult are clones from
/// the original ones combined to the ones in
/// other</remarks>
public SearchResult Intersect(SearchResult other)
{
SearchResult result = new SearchResult();
foreach (SearchHit hit in _hits)
{
SearchHit otherHit = other.FindSearchHit(hit.Record);
if (null != otherHit)
{
SearchHit resultingHit = hit.Clone();
resultingHit.Combine(otherHit);
result.Add(resultingHit);
}
}
return result;
}
