Lucene.Net  3.0.3
Lucene.Net is a port of the Lucene search engine library, written in C# and targeted at .NET runtime users.
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ExactPhraseScorer.cs
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17 
18 using System;
19 
20 using Lucene.Net.Index;
21 
22 namespace Lucene.Net.Search
23 {
24 
26  {
27 
28  internal ExactPhraseScorer(Weight weight, TermPositions[] tps, int[] offsets, Similarity similarity, byte[] norms):base(weight, tps, offsets, similarity, norms)
29  {
30  }
31 
32  protected internal override float PhraseFreq()
33  {
34  // sort list with pq
35  pq.Clear();
36  for (PhrasePositions pp = first; pp != null; pp = pp.next)
37  {
38  pp.FirstPosition();
39  pq.Add(pp); // build pq from list
40  }
41  PqToList(); // rebuild list from pq
42 
43  // for counting how many times the exact phrase is found in current document,
44  // just count how many times all PhrasePosition's have exactly the same position.
45  int freq = 0;
46  do
47  {
48  // find position w/ all terms
49  while (first.position < last.position)
50  {
51  // scan forward in first
52  do
53  {
54  if (!first.NextPosition())
55  return freq;
56  }
57  while (first.position < last.position);
58  FirstToLast();
59  }
60  freq++; // all equal: a match
61  }
62  while (last.NextPosition());
63 
64  return freq;
65  }
66  }
67 }