[LUCENE-9096] Implementation of CompressingTermVectorsWriter.flushOffsets can be simpler

• Type: Improvement
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 8.2
• Fix Version/s: 8.5
• Component/s: core/codecs
• Lucene Fields: New
• Assignee: Unassigned
• Reporter: kkewwei
• Created: 17/Dec/19 03:30
• Updated: 24/Mar/20 12:44
• Resolved: 06/Jan/20 08:23

Description

In CompressingTermVectorsWriter.flushOffsets,  we count 

sumPos and sumOffsets by the way

for (int i = 0; i < fd.numTerms; ++i) { 
  int previousPos = 0;
  int previousOff = 0;
  for (int j = 0; j < fd.freqs[i]; ++j) { 
    final int position = positionsBuf[fd.posStart + pos];
    final int startOffset = startOffsetsBuf[fd.offStart + pos];
    sumPos[fieldNumOff] += position - previousPos; 
    sumOffsets[fieldNumOff] += startOffset - previousOff; 
    previousPos = position;
    previousOff = startOffset;
    ++pos;
  }
}

we always use the position - previousPos,  it can be summarized like this: 

(position5-position4)+(position4-position3)+(position3-position2)+(position2-position1)

If we should simplify it: position5-position1

 

Issue Links

• links to: GitHub Pull Request #1125