Module org.apache.lucene.suggest

Package org.apache.lucene.search.suggest

Class SortedInputIterator

java.lang.Object

org.apache.lucene.search.suggest.SortedInputIterator

All Implemented Interfaces:

InputIterator, BytesRefIterator

Direct Known Subclasses:

WFSTCompletionLookup.WFSTInputIterator

public class SortedInputIterator
extends Object
implements InputIterator

This wrapper buffers incoming elements and makes sure they are sorted based on given comparator.

Nested Class Summary

Nested classes/interfaces inherited from interface org.apache.lucene.search.suggest.InputIterator

InputIterator.InputIteratorWrapper

Field Summary

Fields

Modifier and Type	Field	Description
private final Comparator<BytesRef>	comparator
private Set<BytesRef>	contexts
private boolean	done
private final boolean	hasContexts
private final boolean	hasPayloads
private BytesRef	payload
private final OfflineSorter.ByteSequencesReader	reader
private final InputIterator	source
private final Directory	tempDir
private final String	tempFileNamePrefix
private IndexOutput	tempInput
private String	tempSortedFileName
private final Comparator<BytesRef>	tieBreakByCostComparator	Sortes by BytesRef (ascending) then cost (ascending).
private long	weight

Fields inherited from interface org.apache.lucene.search.suggest.InputIterator

EMPTY

Constructor Summary

Constructors

Constructor	Description
SortedInputIterator(Directory tempDir, String tempFileNamePrefix, InputIterator source)	Creates a new sorted wrapper, using natural order for sorting.
SortedInputIterator(Directory tempDir, String tempFileNamePrefix, InputIterator source, Comparator<BytesRef> comparator)	Creates a new sorted wrapper, sorting by BytesRef (ascending) then cost (ascending).

Method Summary

Modifier and Type	Method	Description
private void	close()
Set<BytesRef>	contexts()	A term's contexts context can be used to filter suggestions.
protected long	decode(BytesRef scratch, ByteArrayDataInput tmpInput)	decodes the weight at the current position
protected Set<BytesRef>	decodeContexts(BytesRef scratch, ByteArrayDataInput tmpInput)	decodes the contexts at the current position
protected BytesRef	decodePayload(BytesRef scratch, ByteArrayDataInput tmpInput)	decodes the payload at the current position
protected void	encode(OfflineSorter.ByteSequencesWriter writer, ByteArrayDataOutput output, byte[] buffer, BytesRef spare, BytesRef payload, Set<BytesRef> contexts, long weight)	encodes an entry (bytes+(contexts)+(payload)+weight) to the provided writer
boolean	hasContexts()	Returns true if the iterator has contexts
boolean	hasPayloads()	Returns true if the iterator has payloads
BytesRef	next()	Increments the iteration to the next BytesRef in the iterator.
BytesRef	payload()	An arbitrary byte[] to record per suggestion.
private OfflineSorter.ByteSequencesReader	sort()
long	weight()	A term's weight, higher numbers mean better suggestions.

Methods inherited from class java.lang.Object

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

Field Details

source

private final InputIterator source

tempInput

private IndexOutput tempInput

tempSortedFileName

private String tempSortedFileName

reader

private final OfflineSorter.ByteSequencesReader reader

comparator

private final Comparator<BytesRef> comparator

hasPayloads

private final boolean hasPayloads

hasContexts

private final boolean hasContexts

tempDir

private final Directory tempDir

tempFileNamePrefix

private final String tempFileNamePrefix

done

private boolean done

weight

private long weight

payload

private BytesRef payload

contexts

private Set<BytesRef> contexts

tieBreakByCostComparator

private final Comparator<BytesRef> tieBreakByCostComparator

Sortes by BytesRef (ascending) then cost (ascending).

Constructor Details

SortedInputIterator

public SortedInputIterator(Directory tempDir,
 String tempFileNamePrefix,
 InputIterator source)
                    throws IOException

Creates a new sorted wrapper, using natural order for sorting.

Throws:

IOException

SortedInputIterator

public SortedInputIterator(Directory tempDir,
 String tempFileNamePrefix,
 InputIterator source,
 Comparator<BytesRef> comparator)
                    throws IOException

Creates a new sorted wrapper, sorting by BytesRef (ascending) then cost (ascending).

Throws:

IOException

Method Details

next

public BytesRef next()
              throws IOException

Description copied from interface: BytesRefIterator

Increments the iteration to the next BytesRef in the iterator. Returns the resulting BytesRef or null if the end of the iterator is reached. The returned BytesRef may be re-used across calls to next. After this method returns null, do not call it again: the results are undefined.

Specified by:

next in interface BytesRefIterator

Returns:

the next BytesRef in the iterator or null if the end of the iterator is reached.

Throws:

IOException - If there is a low-level I/O error.

weight

public long weight()

Description copied from interface: InputIterator

A term's weight, higher numbers mean better suggestions.

Specified by:

weight in interface InputIterator

payload

public BytesRef payload()

Description copied from interface: InputIterator

An arbitrary byte[] to record per suggestion. See Lookup.LookupResult.payload to retrieve the payload for each suggestion.

Specified by:

payload in interface InputIterator

hasPayloads

public boolean hasPayloads()

Description copied from interface: InputIterator

Returns true if the iterator has payloads

Specified by:

hasPayloads in interface InputIterator

contexts

public Set<BytesRef> contexts()

Description copied from interface: InputIterator

A term's contexts context can be used to filter suggestions. May return null, if suggest entries do not have any context

Specified by:

contexts in interface InputIterator

hasContexts

public boolean hasContexts()

Description copied from interface: InputIterator

Returns true if the iterator has contexts

Specified by:

hasContexts in interface InputIterator

sort

private OfflineSorter.ByteSequencesReader sort()
                                        throws IOException

Throws:

IOException

close

private void close()
            throws IOException

Throws:

IOException

encode

protected void encode(OfflineSorter.ByteSequencesWriter writer,
 ByteArrayDataOutput output,
 byte[] buffer,
 BytesRef spare,
 BytesRef payload,
 Set<BytesRef> contexts,
 long weight)
               throws IOException

encodes an entry (bytes+(contexts)+(payload)+weight) to the provided writer

Throws:

IOException

decode

protected long decode(BytesRef scratch,
 ByteArrayDataInput tmpInput)

decodes the weight at the current position

decodeContexts

protected Set<BytesRef> decodeContexts(BytesRef scratch,
 ByteArrayDataInput tmpInput)

decodes the contexts at the current position

decodePayload

protected BytesRef decodePayload(BytesRef scratch,
 ByteArrayDataInput tmpInput)

decodes the payload at the current position