org.apache.lucene.search.suggest.document

Class CompletionTokenStream

java.lang.Object

org.apache.lucene.util.AttributeSource

org.apache.lucene.analysis.TokenStream

org.apache.lucene.analysis.TokenFilter

org.apache.lucene.search.suggest.document.CompletionTokenStream

All Implemented Interfaces:

java.io.Closeable, java.lang.AutoCloseable

public final class CompletionTokenStream
extends TokenFilter

A ConcatenateGraphFilter but we can set the payload and provide access to config options.

Nested Class Summary

Nested classes/interfaces inherited from class org.apache.lucene.util.AttributeSource

AttributeSource.State

Field Summary

Fields

Modifier and Type	Field and Description
(package private) TokenStream	inputTokenStream
(package private) int	maxGraphExpansions
private BytesRef	payload
private PayloadAttribute	payloadAttr
(package private) boolean	preservePositionIncrements
(package private) boolean	preserveSep

Fields inherited from class org.apache.lucene.analysis.TokenFilter

input

Fields inherited from class org.apache.lucene.analysis.TokenStream

DEFAULT_TOKEN_ATTRIBUTE_FACTORY

Constructor Summary

Constructors

Constructor and Description
CompletionTokenStream(TokenStream inputTokenStream)
CompletionTokenStream(TokenStream inputTokenStream, boolean preserveSep, boolean preservePositionIncrements, int maxGraphExpansions)

Method Summary

Modifier and Type	Method and Description
boolean	incrementToken() Consumers (i.e., IndexWriter) use this method to advance the stream to the next token.
void	setPayload(BytesRef payload) Sets a payload available throughout successive token stream enumeration
Automaton	toAutomaton() Delegates to...At
Automaton	toAutomaton(boolean unicodeAware) Delegates to...

Methods inherited from class org.apache.lucene.analysis.TokenFilter

close, end, reset

Methods inherited from class org.apache.lucene.util.AttributeSource

addAttribute, addAttributeImpl, captureState, clearAttributes, cloneAttributes, copyTo, endAttributes, equals, getAttribute, getAttributeClassesIterator, getAttributeFactory, getAttributeImplsIterator, hasAttribute, hasAttributes, hashCode, reflectAsString, reflectWith, removeAllAttributes, restoreState, toString

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Field Detail

payloadAttr

private final PayloadAttribute payloadAttr

inputTokenStream

final TokenStream inputTokenStream

preserveSep

final boolean preserveSep

preservePositionIncrements

final boolean preservePositionIncrements

maxGraphExpansions

final int maxGraphExpansions

payload

private BytesRef payload

Constructor Detail

CompletionTokenStream

CompletionTokenStream(TokenStream inputTokenStream)

CompletionTokenStream

CompletionTokenStream(TokenStream inputTokenStream,
                      boolean preserveSep,
                      boolean preservePositionIncrements,
                      int maxGraphExpansions)

Method Detail

setPayload

public void setPayload(BytesRef payload)

Sets a payload available throughout successive token stream enumeration

incrementToken

public boolean incrementToken()
                       throws java.io.IOException

Description copied from class: TokenStream

Consumers (i.e., IndexWriter) use this method to advance the stream to the next token. Implementing classes must implement this method and update the appropriate AttributeImpls with the attributes of the next token.

The producer must make no assumptions about the attributes after the method has been returned: the caller may arbitrarily change it. If the producer needs to preserve the state for subsequent calls, it can use AttributeSource.captureState() to create a copy of the current attribute state.

This method is called for every token of a document, so an efficient implementation is crucial for good performance. To avoid calls to AttributeSource.addAttribute(Class) and AttributeSource.getAttribute(Class), references to all AttributeImpls that this stream uses should be retrieved during instantiation.

To ensure that filters and consumers know which attributes are available, the attributes must be added during instantiation. Filters and consumers are not required to check for availability of attributes in TokenStream.incrementToken().

Specified by:

incrementToken in class TokenStream

Returns:

false for end of stream; true otherwise

Throws:

java.io.IOException

toAutomaton

public Automaton toAutomaton()
                      throws java.io.IOException

Delegates to...At

Throws:

java.io.IOException

See Also:

ConcatenateGraphFilter.toAutomaton()

toAutomaton

public Automaton toAutomaton(boolean unicodeAware)
                      throws java.io.IOException

Delegates to...

Throws:

java.io.IOException

See Also:

ConcatenateGraphFilter.toAutomaton(boolean)