// This is a simplified query builder which works for single Terms and single Phrases
// Returns null, TermQuery, or PhraseQuery
public static Lucene.Net.Search.Query GetFieldQuery(Analyzer analyzer, string field, string queryText)
{
TokenStream stream = analyzer.TokenStream(field, new StringReader(queryText));
TokenFilter filter = new CachingTokenFilter(stream);
filter.Reset();
// This attribute way of getting token properties isn't very good, but it's the non-obsolete one.
var attr1 = filter.GetAttribute <ITermAttribute>();
Func <string> getText = () => attr1 != null ? attr1.Term : null;
Func <int> getPositionIncrement;
if (filter.HasAttribute <IPositionIncrementAttribute>())
{
var attr = filter.GetAttribute <IPositionIncrementAttribute>();
getPositionIncrement = () => attr.PositionIncrement;
}
else
{
getPositionIncrement = () => 1;
}
// 0 tokens
if (!filter.IncrementToken())
{
return(new BooleanQuery());
}
// 1 token?
string token1 = getText();
int position = 0;
if (!filter.IncrementToken())
{
return(new TermQuery(new Term(field, token1)));
}
// many tokens - handle first token
PhraseQuery ret = new PhraseQuery();
ret.Add(new Term(field, token1));
do
{
// handle rest of tokens
string tokenNext = getText();
position += getPositionIncrement();
ret.Add(new Term(field, tokenNext), position);
}while (filter.IncrementToken());
return(ret);
}
protected override IQueryNode PostProcessNode(IQueryNode node)
{
if (node is ITextableQueryNode &&
!(node is WildcardQueryNode) &&
!(node is FuzzyQueryNode) &&
!(node is RegexpQueryNode) &&
!(node.Parent is IRangeQueryNode))
{
FieldQueryNode fieldNode = ((FieldQueryNode)node);
string text = fieldNode.GetTextAsString();
string field = fieldNode.GetFieldAsString();
CachingTokenFilter buffer = null;
IPositionIncrementAttribute posIncrAtt = null;
int numTokens = 0;
int positionCount = 0;
bool severalTokensAtSamePosition = false;
TokenStream source = null;
try
{
source = this.analyzer.GetTokenStream(field, text);
source.Reset();
buffer = new CachingTokenFilter(source);
if (buffer.HasAttribute <IPositionIncrementAttribute>())
{
posIncrAtt = buffer.GetAttribute <IPositionIncrementAttribute>();
}
try
{
while (buffer.IncrementToken())
{
numTokens++;
int positionIncrement = (posIncrAtt != null) ? posIncrAtt
.PositionIncrement : 1;
if (positionIncrement != 0)
{
positionCount += positionIncrement;
}
else
{
severalTokensAtSamePosition = true;
}
}
}
#pragma warning disable 168
catch (IOException e)
#pragma warning restore 168
{
// ignore
}
}
catch (IOException e)
{
throw new Exception(e.ToString(), e);
}
finally
{
IOUtils.DisposeWhileHandlingException(source);
}
// rewind the buffer stream
buffer.Reset();
if (!buffer.HasAttribute <ICharTermAttribute>())
{
return(new NoTokenFoundQueryNode());
}
ICharTermAttribute termAtt = buffer.GetAttribute <ICharTermAttribute>();
if (numTokens == 0)
{
return(new NoTokenFoundQueryNode());
}
else if (numTokens == 1)
{
string term = null;
try
{
bool hasNext;
hasNext = buffer.IncrementToken();
if (Debugging.AssertsEnabled)
{
Debugging.Assert(hasNext == true);
}
term = termAtt.ToString();
}
catch (IOException) // LUCENENET: IDE0059: Remove unnecessary value assignment
{
// safe to ignore, because we know the number of tokens
}
fieldNode.Text = term.AsCharSequence();
return(fieldNode);
}
else if (severalTokensAtSamePosition || !(node is QuotedFieldQueryNode))
{
if (positionCount == 1 || !(node is QuotedFieldQueryNode))
{
// no phrase query:
if (positionCount == 1)
{
// simple case: only one position, with synonyms
List <IQueryNode> children = new List <IQueryNode>();
for (int i = 0; i < numTokens; i++)
{
string term = null;
try
{
bool hasNext = buffer.IncrementToken();
if (Debugging.AssertsEnabled)
{
Debugging.Assert(hasNext == true);
}
term = termAtt.ToString();
}
catch (IOException) // LUCENENET: IDE0059: Remove unnecessary value assignment
{
// safe to ignore, because we know the number of tokens
}
children.Add(new FieldQueryNode(field, term, -1, -1));
}
return(new GroupQueryNode(
new StandardBooleanQueryNode(children, positionCount == 1)));
}
else
{
// multiple positions
IQueryNode q = new StandardBooleanQueryNode(Collections.EmptyList <IQueryNode>(), false);
IQueryNode currentQuery = null;
for (int i = 0; i < numTokens; i++)
{
string term = null;
try
{
bool hasNext = buffer.IncrementToken();
if (Debugging.AssertsEnabled)
{
Debugging.Assert(hasNext == true);
}
term = termAtt.ToString();
}
catch (IOException) // LUCENENET: IDE0059: Remove unnecessary value assignment
{
// safe to ignore, because we know the number of tokens
}
if (posIncrAtt != null && posIncrAtt.PositionIncrement == 0)
{
if (!(currentQuery is BooleanQueryNode))
{
IQueryNode t = currentQuery;
currentQuery = new StandardBooleanQueryNode(Collections.EmptyList <IQueryNode>(), true);
((BooleanQueryNode)currentQuery).Add(t);
}
((BooleanQueryNode)currentQuery).Add(new FieldQueryNode(field, term, -1, -1));
}
else
{
if (currentQuery != null)
{
if (this.defaultOperator == Operator.OR)
{
q.Add(currentQuery);
}
else
{
q.Add(new ModifierQueryNode(currentQuery, Modifier.MOD_REQ));
}
}
currentQuery = new FieldQueryNode(field, term, -1, -1);
}
}
if (this.defaultOperator == Operator.OR)
{
q.Add(currentQuery);
}
else
{
q.Add(new ModifierQueryNode(currentQuery, Modifier.MOD_REQ));
}
if (q is BooleanQueryNode)
{
q = new GroupQueryNode(q);
}
return(q);
}
}
else
{
// phrase query:
MultiPhraseQueryNode mpq = new MultiPhraseQueryNode();
List <FieldQueryNode> multiTerms = new List <FieldQueryNode>();
int position = -1;
int i = 0;
int termGroupCount = 0;
for (; i < numTokens; i++)
{
string term = null;
int positionIncrement = 1;
try
{
bool hasNext = buffer.IncrementToken();
if (Debugging.AssertsEnabled)
{
Debugging.Assert(hasNext == true);
}
term = termAtt.ToString();
if (posIncrAtt != null)
{
positionIncrement = posIncrAtt.PositionIncrement;
}
}
catch (IOException) // LUCENENET: IDE0059: Remove unnecessary value assignment
{
// safe to ignore, because we know the number of tokens
}
if (positionIncrement > 0 && multiTerms.Count > 0)
{
foreach (FieldQueryNode termNode in multiTerms)
{
if (this.positionIncrementsEnabled)
{
termNode.PositionIncrement = position;
}
else
{
termNode.PositionIncrement = termGroupCount;
}
mpq.Add(termNode);
}
// Only increment once for each "group" of
// terms that were in the same position:
termGroupCount++;
multiTerms.Clear();
}
position += positionIncrement;
multiTerms.Add(new FieldQueryNode(field, term, -1, -1));
}
foreach (FieldQueryNode termNode in multiTerms)
{
if (this.positionIncrementsEnabled)
{
termNode.PositionIncrement = position;
}
else
{
termNode.PositionIncrement = termGroupCount;
}
mpq.Add(termNode);
}
return(mpq);
}
}
else
{
TokenizedPhraseQueryNode pq = new TokenizedPhraseQueryNode();
int position = -1;
for (int i = 0; i < numTokens; i++)
{
string term = null;
int positionIncrement = 1;
try
{
bool hasNext = buffer.IncrementToken();
if (Debugging.AssertsEnabled)
{
Debugging.Assert(hasNext == true);
}
term = termAtt.ToString();
if (posIncrAtt != null)
{
positionIncrement = posIncrAtt.PositionIncrement;
}
}
catch (IOException) // LUCENENET: IDE0059: Remove unnecessary value assignment
{
// safe to ignore, because we know the number of tokens
}
FieldQueryNode newFieldNode = new FieldQueryNode(field, term, -1, -1);
if (this.positionIncrementsEnabled)
{
position += positionIncrement;
newFieldNode.PositionIncrement = position;
}
else
{
newFieldNode.PositionIncrement = i;
}
pq.Add(newFieldNode);
}
return(pq);
}
}
return(node);
}
/// <summary>
/// Creates a query from the analysis chain.
/// <para/>
/// Expert: this is more useful for subclasses such as queryparsers.
/// If using this class directly, just use <see cref="CreateBooleanQuery(string, string)"/>
/// and <see cref="CreatePhraseQuery(string, string)"/>. </summary>
/// <param name="analyzer"> Analyzer used for this query. </param>
/// <param name="operator"> Default boolean operator used for this query. </param>
/// <param name="field"> Field to create queries against. </param>
/// <param name="queryText"> Text to be passed to the analysis chain. </param>
/// <param name="quoted"> <c>true</c> if phrases should be generated when terms occur at more than one position. </param>
/// <param name="phraseSlop"> Slop factor for phrase/multiphrase queries. </param>
protected Query CreateFieldQuery(Analyzer analyzer, Occur @operator, string field, string queryText, bool quoted, int phraseSlop)
{
Debug.Assert(@operator == Occur.SHOULD || @operator == Occur.MUST);
// Use the analyzer to get all the tokens, and then build a TermQuery,
// PhraseQuery, or nothing based on the term count
CachingTokenFilter buffer = null;
ITermToBytesRefAttribute termAtt = null;
IPositionIncrementAttribute posIncrAtt = null;
int numTokens = 0;
int positionCount = 0;
bool severalTokensAtSamePosition = false;
bool hasMoreTokens = false;
TokenStream source = null;
try
{
source = analyzer.GetTokenStream(field, new StringReader(queryText));
source.Reset();
buffer = new CachingTokenFilter(source);
buffer.Reset();
if (buffer.HasAttribute <ITermToBytesRefAttribute>())
{
termAtt = buffer.GetAttribute <ITermToBytesRefAttribute>();
}
if (buffer.HasAttribute <IPositionIncrementAttribute>())
{
posIncrAtt = buffer.GetAttribute <IPositionIncrementAttribute>();
}
if (termAtt != null)
{
try
{
hasMoreTokens = buffer.IncrementToken();
while (hasMoreTokens)
{
numTokens++;
int positionIncrement = (posIncrAtt != null) ? posIncrAtt.PositionIncrement : 1;
if (positionIncrement != 0)
{
positionCount += positionIncrement;
}
else
{
severalTokensAtSamePosition = true;
}
hasMoreTokens = buffer.IncrementToken();
}
}
catch (System.IO.IOException)
{
// ignore
}
}
}
catch (System.IO.IOException e)
{
throw new Exception("Error analyzing query text", e);
}
finally
{
IOUtils.DisposeWhileHandlingException(source);
}
// rewind the buffer stream
buffer.Reset();
BytesRef bytes = termAtt == null ? null : termAtt.BytesRef;
if (numTokens == 0)
{
return(null);
}
else if (numTokens == 1)
{
try
{
bool hasNext = buffer.IncrementToken();
Debug.Assert(hasNext == true);
termAtt.FillBytesRef();
}
catch (System.IO.IOException)
{
// safe to ignore, because we know the number of tokens
}
return(NewTermQuery(new Term(field, BytesRef.DeepCopyOf(bytes))));
}
else
{
if (severalTokensAtSamePosition || (!quoted))
{
if (positionCount == 1 || (!quoted))
{
// no phrase query:
if (positionCount == 1)
{
// simple case: only one position, with synonyms
BooleanQuery q = NewBooleanQuery(true);
for (int i = 0; i < numTokens; i++)
{
try
{
bool hasNext = buffer.IncrementToken();
Debug.Assert(hasNext == true);
termAtt.FillBytesRef();
}
catch (System.IO.IOException)
{
// safe to ignore, because we know the number of tokens
}
Query currentQuery = NewTermQuery(new Term(field, BytesRef.DeepCopyOf(bytes)));
q.Add(currentQuery, Occur.SHOULD);
}
return(q);
}
else
{
// multiple positions
BooleanQuery q = NewBooleanQuery(false);
Query currentQuery = null;
for (int i = 0; i < numTokens; i++)
{
try
{
bool hasNext = buffer.IncrementToken();
Debug.Assert(hasNext == true);
termAtt.FillBytesRef();
}
catch (System.IO.IOException)
{
// safe to ignore, because we know the number of tokens
}
if (posIncrAtt != null && posIncrAtt.PositionIncrement == 0)
{
if (!(currentQuery is BooleanQuery))
{
Query t = currentQuery;
currentQuery = NewBooleanQuery(true);
((BooleanQuery)currentQuery).Add(t, Occur.SHOULD);
}
((BooleanQuery)currentQuery).Add(NewTermQuery(new Term(field, BytesRef.DeepCopyOf(bytes))), Occur.SHOULD);
}
else
{
if (currentQuery != null)
{
q.Add(currentQuery, @operator);
}
currentQuery = NewTermQuery(new Term(field, BytesRef.DeepCopyOf(bytes)));
}
}
q.Add(currentQuery, @operator);
return(q);
}
}
else
{
// phrase query:
MultiPhraseQuery mpq = NewMultiPhraseQuery();
mpq.Slop = phraseSlop;
IList <Term> multiTerms = new List <Term>();
int position = -1;
for (int i = 0; i < numTokens; i++)
{
int positionIncrement = 1;
try
{
bool hasNext = buffer.IncrementToken();
Debug.Assert(hasNext == true);
termAtt.FillBytesRef();
if (posIncrAtt != null)
{
positionIncrement = posIncrAtt.PositionIncrement;
}
}
catch (System.IO.IOException)
{
// safe to ignore, because we know the number of tokens
}
if (positionIncrement > 0 && multiTerms.Count > 0)
{
if (enablePositionIncrements)
{
mpq.Add(multiTerms.ToArray(), position);
}
else
{
mpq.Add(multiTerms.ToArray());
}
multiTerms.Clear();
}
position += positionIncrement;
multiTerms.Add(new Term(field, BytesRef.DeepCopyOf(bytes)));
}
if (enablePositionIncrements)
{
mpq.Add(multiTerms.ToArray(), position);
}
else
{
mpq.Add(multiTerms.ToArray());
}
return(mpq);
}
}
else
{
PhraseQuery pq = NewPhraseQuery();
pq.Slop = phraseSlop;
int position = -1;
for (int i = 0; i < numTokens; i++)
{
int positionIncrement = 1;
try
{
bool hasNext = buffer.IncrementToken();
Debug.Assert(hasNext == true);
termAtt.FillBytesRef();
if (posIncrAtt != null)
{
positionIncrement = posIncrAtt.PositionIncrement;
}
}
catch (System.IO.IOException)
{
// safe to ignore, because we know the number of tokens
}
if (enablePositionIncrements)
{
position += positionIncrement;
pq.Add(new Term(field, BytesRef.DeepCopyOf(bytes)), position);
}
else
{
pq.Add(new Term(field, BytesRef.DeepCopyOf(bytes)));
}
}
return(pq);
}
}
}
