public override Query Rewrite(IndexReader reader, MultiTermQuery query)
{
FilteredTermEnum enumerator = query.GetEnum(reader);
BooleanQuery result = new BooleanQuery(true);
int count = 0;
try
{
do
{
Term t = enumerator.Term();
if (t != null)
{
TermQuery tq = new TermQuery(t); // found a match
tq.SetBoost(query.GetBoost() * enumerator.Difference()); // set the boost
result.Add(tq, BooleanClause.Occur.SHOULD); // add to query
count++;
}
}while (enumerator.Next());
}
finally
{
enumerator.Close();
}
query.IncTotalNumberOfTerms(count);
return(result);
}
public override Query Rewrite(IndexReader reader)
{
FilteredTermEnum enumerator = GetEnum(reader);
int maxClauseCount = BooleanQuery.GetMaxClauseCount();
ScoreTermQueue stQueue = new ScoreTermQueue(maxClauseCount);
ScoreTerm reusableST = null;
try
{
do
{
float score = 0.0f;
Term t = enumerator.Term();
if (t != null)
{
score = enumerator.Difference();
if (reusableST == null)
{
reusableST = new ScoreTerm(t, score);
}
else if (score >= reusableST.score)
{
// reusableST holds the last "rejected" entry, so, if
// this new score is not better than that, there's no
// need to try inserting it
reusableST.score = score;
reusableST.term = t;
}
else
{
continue;
}
reusableST = (ScoreTerm)stQueue.InsertWithOverflow(reusableST);
}
}while (enumerator.Next());
}
finally
{
enumerator.Close();
}
BooleanQuery query = new BooleanQuery(true);
int size = stQueue.Size();
for (int i = 0; i < size; i++)
{
ScoreTerm st = (ScoreTerm)stQueue.Pop();
TermQuery tq = new TermQuery(st.term); // found a match
tq.SetBoost(GetBoost() * st.score); // set the boost
query.Add(tq, BooleanClause.Occur.SHOULD); // add to query
}
return(query);
}
public override Query Rewrite(IndexReader reader)
{
FilteredTermEnum enumerator = GetEnum(reader);
int maxClauseCount = BooleanQuery.GetMaxClauseCount();
ScoreTermQueue stQueue = new ScoreTermQueue(maxClauseCount);
try
{
do
{
float minScore = 0.0f;
float score = 0.0f;
Term t = enumerator.Term();
if (t != null)
{
score = enumerator.Difference();
// terms come in alphabetical order, therefore if queue is full and score
// not bigger than minScore, we can skip
if (stQueue.Size() < maxClauseCount || score > minScore)
{
stQueue.Insert(new ScoreTerm(t, score));
minScore = ((ScoreTerm)stQueue.Top()).score; // maintain minScore
}
}
}while (enumerator.Next());
}
finally
{
enumerator.Close();
}
BooleanQuery query = new BooleanQuery(true);
int size = stQueue.Size();
for (int i = 0; i < size; i++)
{
ScoreTerm st = (ScoreTerm)stQueue.Pop();
TermQuery tq = new TermQuery(st.term); // found a match
tq.SetBoost(GetBoost() * st.score); // set the boost
query.Add(tq, BooleanClause.Occur.SHOULD); // add to query
}
return(query);
}
public override Query Rewrite(IndexReader reader)
{
FilteredTermEnum enumerator = GetEnum(reader);
BooleanQuery query = new BooleanQuery(true);
try
{
do
{
Term t = enumerator.Term();
if (t != null)
{
TermQuery tq = new TermQuery(t); // found a match
tq.SetBoost(GetBoost() * enumerator.Difference()); // set the boost
query.Add(tq, BooleanClause.Occur.SHOULD); // add to query
}
}while (enumerator.Next());
}
finally
{
enumerator.Close();
}
return(query);
}
public override Query Rewrite(IndexReader reader, IState state)
{
if (!termLongEnough)
{
// can only match if it's exact
return(new TermQuery(Term));
}
int maxSize = BooleanQuery.MaxClauseCount;
// TODO: Java uses a PriorityQueue. Using Linq, we can emulate it,
// however it's considerable slower than the java counterpart.
// this should be a temporary thing, fixed before release
SortedList <ScoreTerm, ScoreTerm> stQueue = new SortedList <ScoreTerm, ScoreTerm>();
FilteredTermEnum enumerator = GetEnum(reader, state);
try
{
ScoreTerm st = new ScoreTerm();
do
{
Term t = enumerator.Term;
if (t == null)
{
break;
}
float score = enumerator.Difference();
//ignore uncompetetive hits
if (stQueue.Count >= maxSize && score <= stQueue.Keys.First().score)
{
continue;
}
// add new entry in PQ
st.term = t;
st.score = score;
stQueue.Add(st, st);
// possibly drop entries from queue
if (stQueue.Count > maxSize)
{
st = stQueue.Keys.First();
stQueue.Remove(st);
}
else
{
st = new ScoreTerm();
}
}while (enumerator.Next(state));
}
finally
{
enumerator.Close();
}
BooleanQuery query = new BooleanQuery(true);
foreach (ScoreTerm st in stQueue.Keys)
{
TermQuery tq = new TermQuery(st.term); // found a match
tq.Boost = Boost * st.score; // set the boost
query.Add(tq, Occur.SHOULD); // add to query
}
return(query);
}