/// <summary>
/// OBS this implementation can only provide values for properties of type <seealso cref="string"/>.
/// Other property types will still be counted as distinct, but {@code client} won't receive <seealso cref="Value"/>
/// instances for those. </summary>
/// <param name="client"> <seealso cref="IndexProgressor.NodeValueClient"/> to get initialized with this progression. </param>
/// <param name="propertyAccessor"> <seealso cref="NodePropertyAccessor"/> for reading property values. </param>
/// <param name="needsValues"> whether or not to load string values. </param>
public override void DistinctValues(Org.Neo4j.Storageengine.Api.schema.IndexProgressor_NodeValueClient client, NodePropertyAccessor propertyAccessor, bool needsValues)
{
try
{
IndexQuery[] noQueries = new IndexQuery[0];
BridgingIndexProgressor multiProgressor = new BridgingIndexProgressor(client, _descriptor.schema().PropertyIds);
Fields fields = MultiFields.getFields(IndexSearcher.IndexReader);
foreach (ValueEncoding valueEncoding in ValueEncoding.values())
{
Terms terms = fields.terms(valueEncoding.key());
if (terms != null)
{
System.Func <BytesRef, Value> valueMaterializer = valueEncoding == ValueEncoding.String && needsValues ? term => Values.stringValue(term.utf8ToString()) : term => null;
TermsEnum termsIterator = terms.GetEnumerator();
if (valueEncoding == ValueEncoding.Number)
{
termsIterator = NumericUtils.filterPrefixCodedLongs(termsIterator);
}
multiProgressor.Initialize(_descriptor, new LuceneDistinctValuesProgressor(termsIterator, client, valueMaterializer), noQueries, IndexOrder.NONE, needsValues);
}
}
client.Initialize(_descriptor, multiProgressor, noQueries, IndexOrder.NONE, needsValues);
}
catch (IOException e)
{
throw new UncheckedIOException(e);
}
}
/// <summary>
/// Returns TermStats[] ordered by the specified comparator
/// </summary>
//JAVA TO C# CONVERTER WARNING: Method 'throws' clauses are not available in .NET:
//ORIGINAL LINE: public static TermStats[] getHighFreqTerms(org.apache.lucene.index.IndexReader reader, int numTerms, String field, java.util.Comparator<TermStats> comparator) throws Exception
public static TermStats[] getHighFreqTerms(IndexReader reader, int numTerms, string field, IComparer <TermStats> comparator)
{
TermStatsQueue tiq = null;
if (field != null)
{
Fields fields = MultiFields.getFields(reader);
if (fields == null)
{
throw new Exception("field " + field + " not found");
}
Terms terms = fields.terms(field);
if (terms != null)
{
TermsEnum termsEnum = terms.iterator(null);
tiq = new TermStatsQueue(numTerms, comparator);
tiq.fill(field, termsEnum);
}
}
else
{
Fields fields = MultiFields.getFields(reader);
if (fields == null)
{
throw new Exception("no fields found for this index");
}
tiq = new TermStatsQueue(numTerms, comparator);
foreach (string fieldName in fields)
{
Terms terms = fields.terms(fieldName);
if (terms != null)
{
tiq.fill(fieldName, terms.iterator(null));
}
}
}
TermStats[] result = new TermStats[tiq.size()];
// we want highest first so we read the queue and populate the array
// starting at the end and work backwards
int count = tiq.size() - 1;
while (tiq.size() != 0)
{
result[count] = tiq.pop();
count--;
}
return(result);
}
