org.apache.lucene.search.spans

Class NearSpansPayloadOrdered

java.lang.Object

org.apache.lucene.search.DocIdSetIterator

org.apache.lucene.search.spans.Spans

org.apache.lucene.search.spans.NearSpansOrdered

org.apache.lucene.search.spans.NearSpansPayloadOrdered

public class NearSpansPayloadOrdered
extends NearSpansOrdered

A NearSpansOrdered that allows collecting payloads. Expert: Only public for subclassing. Most implementations should not need this class

Field Summary

Fields inherited from class org.apache.lucene.search.spans.NearSpansOrdered

matchDoc, matchEnd, matchStart

Fields inherited from class org.apache.lucene.search.spans.Spans

NO_MORE_POSITIONS

Fields inherited from class org.apache.lucene.search.DocIdSetIterator

NO_MORE_DOCS

Constructor Summary

Constructors

Constructor and Description
NearSpansPayloadOrdered(SpanNearQuery query, List<Spans> subSpans)

Method Summary

Methods

Modifier and Type	Method and Description
int	advance(int target) Advances to the first beyond the current whose document number is greater than or equal to target, and returns the document number itself.
TwoPhaseIterator	asTwoPhaseIterator() Return a TwoPhaseIterator view of this ConjunctionSpans.
long	cost() Returns the estimated cost of this DocIdSetIterator.
int	docID() Returns the following: -1 if DocIdSetIterator.nextDoc() or DocIdSetIterator.advance(int) were not called yet.
Collection<byte[]>	getPayload() Return payloads when available.
Spans[]	getSubSpans()
boolean	isPayloadAvailable() Indicates whether payloads are available
int	nextDoc() Advances to the next document in the set and returns the doc it is currently on, or DocIdSetIterator.NO_MORE_DOCS if there are no more docs in the set. NOTE: after the iterator has exhausted you should not call this method, as it may result in unpredicted behavior.
protected boolean	shrinkToAfterShortestMatch() The subSpans are ordered in the same doc, so there is a possible match.
String	toString()

Methods inherited from class org.apache.lucene.search.spans.NearSpansOrdered

endPosition, nextStartPosition, startPosition

Methods inherited from class org.apache.lucene.search.DocIdSetIterator

all, empty, slowAdvance

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Constructor Detail

NearSpansPayloadOrdered

public NearSpansPayloadOrdered(SpanNearQuery query,
                       List<Spans> subSpans)
                        throws IOException

Throws:

IOException

Method Detail

shrinkToAfterShortestMatch

protected boolean shrinkToAfterShortestMatch()
                                      throws IOException

The subSpans are ordered in the same doc, so there is a possible match. Compute the slop while making the match as short as possible by using nextStartPosition on all subSpans, except the last one, in reverse order. Also collect the payloads.

Overrides:

shrinkToAfterShortestMatch in class NearSpansOrdered

Throws:

IOException

getPayload

public Collection<byte[]> getPayload()
                              throws IOException

Return payloads when available.

Overrides:

getPayload in class NearSpansOrdered

Returns:

a List of byte arrays containing the data of this payload, otherwise null if isPayloadAvailable is false

Throws:

IOException - if there is a low-level I/O error

isPayloadAvailable

public boolean isPayloadAvailable()

Indicates whether payloads are available

Overrides:

isPayloadAvailable in class NearSpansOrdered

Returns:

true if there is a payload available at this start/end position that can be loaded

toString

public String toString()

Overrides:

toString in class NearSpansOrdered

docID

public int docID()

Description copied from class: DocIdSetIterator

Returns the following:

• -1 if DocIdSetIterator.nextDoc() or DocIdSetIterator.advance(int) were not called yet.
• DocIdSetIterator.NO_MORE_DOCS if the iterator has exhausted.
• Otherwise it should return the doc ID it is currently on.

Specified by:

docID in class DocIdSetIterator

cost

public long cost()

Description copied from class: DocIdSetIterator

Returns the estimated cost of this DocIdSetIterator.

This is generally an upper bound of the number of documents this iterator might match, but may be a rough heuristic, hardcoded value, or otherwise completely inaccurate.

Specified by:

cost in class DocIdSetIterator

nextDoc

public int nextDoc()
            throws IOException

Description copied from class: DocIdSetIterator

Advances to the next document in the set and returns the doc it is currently on, or DocIdSetIterator.NO_MORE_DOCS if there are no more docs in the set.
NOTE: after the iterator has exhausted you should not call this method, as it may result in unpredicted behavior.

Specified by:

nextDoc in class DocIdSetIterator

Throws:

IOException

advance

public int advance(int target)
            throws IOException

Description copied from class: DocIdSetIterator

Advances to the first beyond the current whose document number is greater than or equal to target, and returns the document number itself. Exhausts the iterator and returns DocIdSetIterator.NO_MORE_DOCS if target is greater than the highest document number in the set.

The behavior of this method is undefined when called with target ≤ current, or after the iterator has exhausted. Both cases may result in unpredicted behavior.

When target > current it behaves as if written:

 int advance(int target) {
   int doc;
   while ((doc = nextDoc()) < target) {
   }
   return doc;
 }
 

Some implementations are considerably more efficient than that.

NOTE: this method may be called with DocIdSetIterator.NO_MORE_DOCS for efficiency by some Scorers. If your implementation cannot efficiently determine that it should exhaust, it is recommended that you check for that value in each call to this method.

Specified by:

advance in class DocIdSetIterator

Throws:

IOException

asTwoPhaseIterator

public TwoPhaseIterator asTwoPhaseIterator()

Return a TwoPhaseIterator view of this ConjunctionSpans.

Overrides:

asTwoPhaseIterator in class Spans

getSubSpans

public Spans[] getSubSpans()