|
/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You 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 IndexInput = Lucene.Net.Store.IndexInput;
using BitVector = Lucene.Net.Util.BitVector;
namespace Lucene.Net.Index
{
public class SegmentTermDocs : TermDocs
{
protected internal SegmentReader parent;
protected internal IndexInput freqStream;
protected internal int count;
protected internal int df;
protected internal BitVector deletedDocs;
internal int doc = 0;
internal int freq;
private int skipInterval;
private int maxSkipLevels;
private DefaultSkipListReader skipListReader;
private long freqBasePointer;
private long proxBasePointer;
private long skipPointer;
private bool haveSkipped;
protected internal bool currentFieldStoresPayloads;
// for testing
public IndexInput FreqStream_ForNUnitTest
{
get { return freqStream; }
set { freqStream = value; }
}
public SegmentTermDocs(SegmentReader parent)
{
this.parent = parent;
this.freqStream = (IndexInput) parent.freqStream.Clone();
this.deletedDocs = parent.deletedDocs;
this.skipInterval = parent.tis.GetSkipInterval();
this.maxSkipLevels = parent.tis.GetMaxSkipLevels();
}
public virtual void Seek(Term term)
{
TermInfo ti = parent.tis.Get(term);
Seek(ti, term);
}
public virtual void Seek(TermEnum termEnum)
{
TermInfo ti;
Term term;
// use comparison of fieldinfos to verify that termEnum belongs to the same segment as this SegmentTermDocs
if (termEnum is SegmentTermEnum && ((SegmentTermEnum) termEnum).fieldInfos == parent.fieldInfos)
{
// optimized case
SegmentTermEnum segmentTermEnum = ((SegmentTermEnum) termEnum);
term = segmentTermEnum.Term();
ti = segmentTermEnum.TermInfo();
}
else
{
// punt case
term = termEnum.Term();
ti = parent.tis.Get(term);
}
Seek(ti, term);
}
internal virtual void Seek(TermInfo ti, Term term)
{
count = 0;
FieldInfo fi = parent.fieldInfos.FieldInfo(term.field);
currentFieldStoresPayloads = (fi != null) ? fi.storePayloads : false;
if (ti == null)
{
df = 0;
}
else
{
df = ti.docFreq;
doc = 0;
freqBasePointer = ti.freqPointer;
proxBasePointer = ti.proxPointer;
skipPointer = freqBasePointer + ti.skipOffset;
freqStream.Seek(freqBasePointer);
haveSkipped = false;
}
}
public virtual void Close()
{
freqStream.Close();
if (skipListReader != null)
skipListReader.Close();
}
public int Doc()
{
return doc;
}
public int Freq()
{
return freq;
}
protected internal virtual void SkippingDoc()
{
}
public virtual bool Next()
{
while (true)
{
if (count == df)
return false;
int docCode = freqStream.ReadVInt();
doc += (int) (((uint) docCode) >> 1); // shift off low bit
if ((docCode & 1) != 0)
// if low bit is set
freq = 1;
// freq is one
else
freq = freqStream.ReadVInt(); // else read freq
count++;
if (deletedDocs == null || !deletedDocs.Get(doc))
break;
SkippingDoc();
}
return true;
}
/// <summary>Optimized implementation. </summary>
public virtual int Read(int[] docs, int[] freqs)
{
int length = docs.Length;
int i = 0;
while (i < length && count < df)
{
// manually inlined call to next() for speed
int docCode = freqStream.ReadVInt();
doc += (int) (((uint) docCode) >> 1); // shift off low bit
if ((docCode & 1) != 0)
// if low bit is set
freq = 1;
// freq is one
else
freq = freqStream.ReadVInt(); // else read freq
count++;
if (deletedDocs == null || !deletedDocs.Get(doc))
{
docs[i] = doc;
freqs[i] = freq;
++i;
}
}
return i;
}
/// <summary>Overridden by SegmentTermPositions to skip in prox stream. </summary>
protected internal virtual void SkipProx(long proxPointer)
{
}
protected internal virtual void SkipProx(long proxPointer, int payloadLength)
{
}
/// <summary>Optimized implementation. </summary>
public virtual bool SkipTo(int target)
{
if (df >= skipInterval)
{
// optimized case
if (skipListReader == null)
skipListReader = new DefaultSkipListReader((IndexInput) freqStream.Clone(), maxSkipLevels, skipInterval); // lazily clone
if (!haveSkipped)
{
// lazily initialize skip stream
skipListReader.Init(skipPointer, freqBasePointer, proxBasePointer, df, currentFieldStoresPayloads);
haveSkipped = true;
}
int newCount = skipListReader.SkipTo(target);
if (newCount > count)
{
freqStream.Seek(skipListReader.GetFreqPointer());
SkipProx(skipListReader.GetProxPointer(), skipListReader.GetPayloadLength());
doc = skipListReader.GetDoc();
count = newCount;
}
}
// done skipping, now just scan
do
{
if (!Next())
return false;
}
while (target > doc);
return true;
}
}
}
|
By viewing downloads associated with this article you agree to the Terms of Service and the article's licence.
If a file you wish to view isn't highlighted, and is a text file (not binary), please
let us know and we'll add colourisation support for it.