org.apache.lucene.search.spans
Class TermSpans

java.lang.Object
  org.apache.lucene.search.spans.TermSpans

All Implemented Interfaces:

PayloadSpans, Spans

public class TermSpans
extends Object
implements PayloadSpans

Expert: Public for extension only

Field Summary

protected int	count
protected int	doc
protected int	freq
protected int	position
protected TermPositions	positions
protected Term	term

Constructor Summary

TermSpans(TermPositions positions, Term term)

Method Summary

int	doc() Returns the document number of the current match.
int	end() Returns the end position of the current match.
Collection	getPayload() Returns the payload data for the current span.
TermPositions	getPositions()
boolean	isPayloadAvailable() Checks if a payload can be loaded at this position.
boolean	next() Move to the next match, returning true iff any such exists.
boolean	skipTo(int target) Skips to the first match beyond the current, whose document number is greater than or equal to target.
int	start() Returns the start position of the current match.
String	toString()

Methods inherited from class java.lang.Object

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

Field Detail

positions

protected TermPositions positions

term

protected Term term

doc

protected int doc

freq

protected int freq

count

protected int count

position

protected int position

Constructor Detail

TermSpans

public TermSpans(TermPositions positions,
                 Term term)
          throws IOException

Throws:

IOException

Method Detail

next

public boolean next()
             throws IOException

Description copied from interface: Spans

Move to the next match, returning true iff any such exists.

Specified by:

next in interface Spans

Throws:

IOException

skipTo

public boolean skipTo(int target)
               throws IOException

Description copied from interface: Spans

Skips to the first match beyond the current, whose document number is greater than or equal to target.

Returns true iff there is such a match.

Behaves as if written:

   boolean skipTo(int target) {
     do {
       if (!next())
             return false;
     } while (target > doc());
     return true;
   }
 

Most implementations are considerably more efficient than that.

Specified by:

skipTo in interface Spans

Throws:

IOException

doc

public int doc()

Description copied from interface: Spans

Returns the document number of the current match. Initially invalid.

Specified by:

doc in interface Spans

start

public int start()

Description copied from interface: Spans

Returns the start position of the current match. Initially invalid.

Specified by:

start in interface Spans

end

public int end()

Description copied from interface: Spans

Returns the end position of the current match. Initially invalid.

Specified by:

end in interface Spans

getPayload

public Collection getPayload()
                      throws IOException

Description copied from interface: PayloadSpans

Returns the payload data for the current span. This is invalid until Spans.next() is called for the first time. This method must not be called more than once after each call of Spans.next(). However, payloads are loaded lazily, so if the payload data for the current position is not needed, this method may not be called at all for performance reasons.

Note that the return type is a collection, thus the ordering should not be relied upon.

WARNING: The status of the Payloads feature is experimental. The APIs introduced here might change in the future and will not be supported anymore in such a case.

Specified by:

getPayload in interface PayloadSpans

Returns:

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

Throws:

IOException

isPayloadAvailable

public boolean isPayloadAvailable()

Description copied from interface: PayloadSpans

Checks if a payload can be loaded at this position.

Payloads can only be loaded once per call to Spans.next().

WARNING: The status of the Payloads feature is experimental. The APIs introduced here might change in the future and will not be supported anymore in such a case.

Specified by:

isPayloadAvailable in interface PayloadSpans

Returns:

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

toString

public String toString()

Overrides:

toString in class Object

getPositions

public TermPositions getPositions()