public virtual string[] CreateFragments(IndexReader reader, int docId,
string fieldName, FieldFragList fieldFragList, int maxNumFragments,
string[] preTags, string[] postTags, IEncoder encoder)
{
// LUCENENET specific - added guard clauses to check for null
if (reader is null)
{
throw new ArgumentNullException(nameof(reader));
}
if (fieldFragList is null)
{
throw new ArgumentNullException(nameof(fieldFragList));
}
if (preTags is null)
{
throw new ArgumentNullException(nameof(preTags));
}
if (postTags is null)
{
throw new ArgumentNullException(nameof(postTags));
}
if (encoder is null)
{
throw new ArgumentNullException(nameof(encoder));
}
if (maxNumFragments < 0)
{
throw new ArgumentOutOfRangeException(nameof(maxNumFragments), "maxNumFragments(" + maxNumFragments + ") must be positive number."); // LUCENENET specific - changed from IllegalArgumentException to ArgumentOutOfRangeException (.NET convention)
}
IList <WeightedFragInfo> fragInfos = fieldFragList.FragInfos;
Field[]
values = GetFields(reader, docId, fieldName);
if (values.Length == 0)
{
return(null);
}
if (discreteMultiValueHighlighting && values.Length > 1)
{
fragInfos = DiscreteMultiValueHighlighting(fragInfos, values);
}
fragInfos = GetWeightedFragInfoList(fragInfos);
int limitFragments = maxNumFragments < fragInfos.Count ? maxNumFragments : fragInfos.Count;
JCG.List <string> fragments = new JCG.List <string>(limitFragments);
StringBuilder buffer = new StringBuilder();
int[] nextValueIndex = { 0 };
for (int n = 0; n < limitFragments; n++)
{
WeightedFragInfo fragInfo = fragInfos[n];
fragments.Add(MakeFragment(buffer, nextValueIndex, values, fragInfo, preTags, postTags, encoder));
}
return(fragments.ToArray(/* new String[fragments.size()] */));
}
public virtual string[] CreateFragments(IndexReader reader, int docId,
string fieldName, FieldFragList fieldFragList, int maxNumFragments,
string[] preTags, string[] postTags, IEncoder encoder)
{
if (maxNumFragments < 0)
{
throw new ArgumentException("maxNumFragments(" + maxNumFragments + ") must be positive number.");
}
IList <WeightedFragInfo> fragInfos = fieldFragList.FragInfos;
Field[]
values = GetFields(reader, docId, fieldName);
if (values.Length == 0)
{
return(null);
}
if (discreteMultiValueHighlighting && values.Length > 1)
{
fragInfos = DiscreteMultiValueHighlighting(fragInfos, values);
}
fragInfos = GetWeightedFragInfoList(fragInfos);
int limitFragments = maxNumFragments < fragInfos.Count ? maxNumFragments : fragInfos.Count;
List <string> fragments = new List <string>(limitFragments);
StringBuilder buffer = new StringBuilder();
int[] nextValueIndex = { 0 };
for (int n = 0; n < limitFragments; n++)
{
WeightedFragInfo fragInfo = fragInfos[n];
fragments.Add(MakeFragment(buffer, nextValueIndex, values, fragInfo, preTags, postTags, encoder));
}
return(fragments.ToArray(/* new String[fragments.size()] */));
}
protected virtual IList <WeightedFragInfo> DiscreteMultiValueHighlighting(IList <WeightedFragInfo> fragInfos, Field[] fields)
{
IDictionary <string, List <WeightedFragInfo> > fieldNameToFragInfos = new Dictionary <string, List <WeightedFragInfo> >();
foreach (Field field in fields)
{
fieldNameToFragInfos[field.Name] = new List <WeightedFragInfo>();
}
foreach (WeightedFragInfo fragInfo in fragInfos)
{
int fieldStart;
int fieldEnd = 0;
foreach (Field field in fields)
{
if (field.GetStringValue().Length == 0)
{
fieldEnd++;
continue;
}
fieldStart = fieldEnd;
fieldEnd += field.GetStringValue().Length + 1; // + 1 for going to next field with same name.
if (fragInfo.StartOffset >= fieldStart && fragInfo.EndOffset >= fieldStart &&
fragInfo.StartOffset <= fieldEnd && fragInfo.EndOffset <= fieldEnd)
{
fieldNameToFragInfos[field.Name].Add(fragInfo);
goto fragInfos_continue;
}
if (!fragInfo.SubInfos.Any())
{
goto fragInfos_continue;
}
Toffs firstToffs = fragInfo.SubInfos[0].TermsOffsets[0];
if (fragInfo.StartOffset >= fieldEnd || firstToffs.StartOffset >= fieldEnd)
{
continue;
}
int fragStart = fieldStart;
if (fragInfo.StartOffset > fieldStart && fragInfo.StartOffset < fieldEnd)
{
fragStart = fragInfo.StartOffset;
}
int fragEnd = fieldEnd;
if (fragInfo.EndOffset > fieldStart && fragInfo.EndOffset < fieldEnd)
{
fragEnd = fragInfo.EndOffset;
}
// LUCENENET specific - track the fragInfo.SubInfos items to delete
List <SubInfo> fragInfo_SubInfos_ToDelete = new List <SubInfo>();
List <SubInfo> subInfos = new List <SubInfo>();
float boost = 0.0f; // The boost of the new info will be the sum of the boosts of its SubInfos
using (IEnumerator <SubInfo> subInfoIterator = fragInfo.SubInfos.GetEnumerator())
{
while (subInfoIterator.MoveNext())
{
SubInfo subInfo = subInfoIterator.Current;
List <Toffs> toffsList = new List <Toffs>();
using (IEnumerator <Toffs> toffsIterator = subInfo.TermsOffsets.GetEnumerator())
{
while (toffsIterator.MoveNext())
{
Toffs toffs = toffsIterator.Current;
if (toffs.StartOffset >= fieldStart && toffs.EndOffset <= fieldEnd)
{
toffsList.Add(toffs);
//toffsIterator.Remove();
}
}
}
if (toffsList.Any())
{
// LUCENENET NOTE: Instead of removing during iteration (which isn't allowed in .NET when using an IEnumerator),
// we just remove the items at this point. We only get here if there are items to remove.
subInfo.TermsOffsets.RemoveAll(toffsList);
subInfos.Add(new SubInfo(subInfo.Text, toffsList, subInfo.Seqnum, subInfo.Boost));
boost += subInfo.Boost;
}
if (!subInfo.TermsOffsets.Any())
{
//subInfoIterator.Remove();
fragInfo_SubInfos_ToDelete.Add(subInfo);
}
}
}
// LUCENENET specific - now that we are done iterating the loop, it is safe to delete
// the items we earmarked. Note this is just a list of pointers, so it doens't consume
// much RAM.
fragInfo.SubInfos.RemoveAll(fragInfo_SubInfos_ToDelete);
WeightedFragInfo weightedFragInfo = new WeightedFragInfo(fragStart, fragEnd, subInfos, boost);
fieldNameToFragInfos[field.Name].Add(weightedFragInfo);
}
fragInfos_continue : { }
}
List <WeightedFragInfo> result = new List <WeightedFragInfo>();
foreach (List <WeightedFragInfo> weightedFragInfos in fieldNameToFragInfos.Values)
{
result.AddRange(weightedFragInfos);
}
CollectionUtil.TimSort(result, new DiscreteMultiValueHighlightingComparerAnonymousHelper());
return(result);
}
protected virtual string MakeFragment(StringBuilder buffer, int[] index, Field[] values, WeightedFragInfo fragInfo,
string[] preTags, string[] postTags, IEncoder encoder)
{
StringBuilder fragment = new StringBuilder();
int s = fragInfo.StartOffset;
int[] modifiedStartOffset = { s };
string src = GetFragmentSourceMSO(buffer, index, values, s, fragInfo.EndOffset, modifiedStartOffset);
int srcIndex = 0;
foreach (SubInfo subInfo in fragInfo.SubInfos)
{
foreach (Toffs to in subInfo.TermsOffsets)
{
fragment
.Append(encoder.EncodeText(src.Substring(srcIndex, (to.StartOffset - modifiedStartOffset[0]) - srcIndex)))
.Append(GetPreTag(preTags, subInfo.Seqnum))
.Append(encoder.EncodeText(src.Substring(to.StartOffset - modifiedStartOffset[0], (to.EndOffset - modifiedStartOffset[0]) - (to.StartOffset - modifiedStartOffset[0]))))
.Append(GetPostTag(postTags, subInfo.Seqnum));
srcIndex = to.EndOffset - modifiedStartOffset[0];
}
}
fragment.Append(encoder.EncodeText(src.Substring(srcIndex)));
return(fragment.ToString());
}
protected virtual IList <WeightedFragInfo> DiscreteMultiValueHighlighting(IList <WeightedFragInfo> fragInfos, Field[] fields)
{
IDictionary <string, IList <WeightedFragInfo> > fieldNameToFragInfos = new Dictionary <string, IList <WeightedFragInfo> >();
foreach (Field field in fields)
{
fieldNameToFragInfos[field.Name] = new JCG.List <WeightedFragInfo>();
}
foreach (WeightedFragInfo fragInfo in fragInfos)
{
int fieldStart;
int fieldEnd = 0;
foreach (Field field in fields)
{
if (field.GetStringValue().Length == 0)
{
fieldEnd++;
continue;
}
fieldStart = fieldEnd;
fieldEnd += field.GetStringValue().Length + 1; // + 1 for going to next field with same name.
if (fragInfo.StartOffset >= fieldStart && fragInfo.EndOffset >= fieldStart &&
fragInfo.StartOffset <= fieldEnd && fragInfo.EndOffset <= fieldEnd)
{
fieldNameToFragInfos[field.Name].Add(fragInfo);
goto fragInfos_continue;
}
if (fragInfo.SubInfos.Count == 0)
{
goto fragInfos_continue;
}
Toffs firstToffs = fragInfo.SubInfos[0].TermsOffsets[0];
if (fragInfo.StartOffset >= fieldEnd || firstToffs.StartOffset >= fieldEnd)
{
continue;
}
int fragStart = fieldStart;
if (fragInfo.StartOffset > fieldStart && fragInfo.StartOffset < fieldEnd)
{
fragStart = fragInfo.StartOffset;
}
int fragEnd = fieldEnd;
if (fragInfo.EndOffset > fieldStart && fragInfo.EndOffset < fieldEnd)
{
fragEnd = fragInfo.EndOffset;
}
// LUCENENET NOTE: Instead of removing during iteration (which isn't allowed in .NET when using an IEnumerator),
// We use the IList<T>.RemoveAll() extension method of J2N. This removal happens in a forward way, but since it
// accepts a predicate, we can put in the rest of Lucene's logic without doing something expensive like keeping
// track of the items to remove in a separate collection. In a nutshell, any time Lucene calls iterator.remove(),
// we return true and any time it is skipped, we return false.
IList <SubInfo> subInfos = new JCG.List <SubInfo>();
float boost = 0.0f; // The boost of the new info will be the sum of the boosts of its SubInfos
fragInfo.SubInfos.RemoveAll((subInfo) =>
{
IList <Toffs> toffsList = new JCG.List <Toffs>();
subInfo.TermsOffsets.RemoveAll((toffs) =>
{
if (toffs.StartOffset >= fieldStart && toffs.EndOffset <= fieldEnd)
{
toffsList.Add(toffs);
return(true); // Remove
}
return(false);
});
if (toffsList.Count > 0)
{
subInfos.Add(new SubInfo(subInfo.Text, toffsList, subInfo.Seqnum, subInfo.Boost));
boost += subInfo.Boost;
}
if (subInfo.TermsOffsets.Count == 0)
{
return(true); // Remove
}
return(false);
});
WeightedFragInfo weightedFragInfo = new WeightedFragInfo(fragStart, fragEnd, subInfos, boost);
fieldNameToFragInfos[field.Name].Add(weightedFragInfo);
}
fragInfos_continue : { }
}
JCG.List <WeightedFragInfo> result = new JCG.List <WeightedFragInfo>();
foreach (IList <WeightedFragInfo> weightedFragInfos in fieldNameToFragInfos.Values)
{
result.AddRange(weightedFragInfos);
}
CollectionUtil.TimSort(result, Comparer <WeightedFragInfo> .Create((info1, info2) => info1.StartOffset - info2.StartOffset));
return(result);
}
