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.core.fieldInfos)
{
// optimized case
SegmentTermEnum segmentTermEnum = ((SegmentTermEnum)termEnum);
term = segmentTermEnum.Term();
ti = segmentTermEnum.TermInfo();
}
else
{
// punt case
term = termEnum.Term();
ti = parent.core.GetTermsReader().Get(term);
}
Seek(ti, term);
}
internal TermInfosReader(Directory dir, System.String seg, FieldInfos fis, int readBufferSize, int indexDivisor)
{
bool success = false;
if (indexDivisor < 1 && indexDivisor != -1)
{
throw new System.ArgumentException("indexDivisor must be -1 (don't load terms index) or greater than 0: got " + indexDivisor);
}
try
{
directory = dir;
segment = seg;
fieldInfos = fis;
origEnum = new SegmentTermEnum(directory.OpenInput(segment + "." + IndexFileNames.TERMS_EXTENSION, readBufferSize), fieldInfos, false);
size = origEnum.size;
if (indexDivisor != -1)
{
// Load terms index
totalIndexInterval = origEnum.indexInterval * indexDivisor;
SegmentTermEnum indexEnum = new SegmentTermEnum(directory.OpenInput(segment + "." + IndexFileNames.TERMS_INDEX_EXTENSION, readBufferSize), fieldInfos, true);
try
{
int indexSize = 1 + ((int)indexEnum.size - 1) / indexDivisor; // otherwise read index
indexTerms = new Term[indexSize];
indexInfos = new TermInfo[indexSize];
indexPointers = new long[indexSize];
for (int i = 0; indexEnum.Next(); i++)
{
indexTerms[i] = indexEnum.Term();
indexInfos[i] = indexEnum.TermInfo();
indexPointers[i] = indexEnum.indexPointer;
for (int j = 1; j < indexDivisor; j++)
{
if (!indexEnum.Next())
{
break;
}
}
}
}
finally
{
indexEnum.Close();
}
}
else
{
// Do not load terms index:
totalIndexInterval = -1;
indexTerms = null;
indexInfos = null;
indexPointers = null;
}
success = true;
}
finally
{
// With lock-less commits, it's entirely possible (and
// fine) to hit a FileNotFound exception above. In
// this case, we want to explicitly close any subset
// of things that were opened so that we don't have to
// wait for a GC to do so.
if (!success)
{
Close();
}
}
}
/// <summary>Returns the TermInfo for a Term in the set, or null. </summary>
private TermInfo Get(Term term, bool useCache)
{
if (size == 0)
{
return(null);
}
EnsureIndexIsRead();
TermInfo ti;
ThreadResources resources = GetThreadResources();
Mono.Lucene.Net.Util.Cache.Cache cache = null;
if (useCache)
{
cache = resources.termInfoCache;
// check the cache first if the term was recently looked up
ti = (TermInfo)cache.Get(term);
if (ti != null)
{
return(ti);
}
}
// optimize sequential access: first try scanning cached enum w/o seeking
SegmentTermEnum enumerator = resources.termEnum;
if (enumerator.Term() != null && ((enumerator.Prev() != null && term.CompareTo(enumerator.Prev()) > 0) || term.CompareTo(enumerator.Term()) >= 0))
{
int enumOffset = (int)(enumerator.position / totalIndexInterval) + 1;
if (indexTerms.Length == enumOffset || term.CompareTo(indexTerms[enumOffset]) < 0)
{
// no need to seek
int numScans = enumerator.ScanTo(term);
if (enumerator.Term() != null && term.CompareTo(enumerator.Term()) == 0)
{
ti = enumerator.TermInfo();
if (cache != null && numScans > 1)
{
// we only want to put this TermInfo into the cache if
// scanEnum skipped more than one dictionary entry.
// This prevents RangeQueries or WildcardQueries to
// wipe out the cache when they iterate over a large numbers
// of terms in order
cache.Put(term, ti);
}
}
else
{
ti = null;
}
return(ti);
}
}
// random-access: must seek
SeekEnum(enumerator, GetIndexOffset(term));
enumerator.ScanTo(term);
if (enumerator.Term() != null && term.CompareTo(enumerator.Term()) == 0)
{
ti = enumerator.TermInfo();
if (cache != null)
{
cache.Put(term, ti);
}
}
else
{
ti = null;
}
return(ti);
}