/*
* Copyright 2004 The Apache Software Foundation
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
using System;
using Lucene.Net.Index;
namespace Lucene.Net.Search{
sealed class PhrasePositions
{
internal int doc; // current doc
internal int position; // position in doc
internal int count; // remaining pos in this doc
internal int offset; // position in phrase
internal TermPositions tp; // stream of positions
internal PhrasePositions next; // used to make lists
internal PhrasePositions(TermPositions t, int o)
{
tp = t;
offset = o;
}
internal bool Next()
{
// increments to next doc
if (!tp.Next())
{
tp.Close(); // close stream
doc = System.Int32.MaxValue; // sentinel value
return false;
}
doc = tp.Doc();
position = 0;
return true;
}
internal bool SkipTo(int target)
{
if (!tp.SkipTo(target))
{
tp.Close(); // close stream
doc = System.Int32.MaxValue; // sentinel value
return false;
}
doc = tp.Doc();
position = 0;
return true;
}
internal void FirstPosition()
{
count = tp.Freq(); // read first pos
NextPosition();
}
internal bool NextPosition()
{
if (count-- > 0)
{
// read subsequent pos's
position = tp.NextPosition() - offset;
return true;
}
else
return false;
}
}
}
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