org.apache.lucene.facet.index.streaming
Class CategoryTokenizerBase

java.lang.Object
  org.apache.lucene.util.AttributeSource
      org.apache.lucene.analysis.TokenStream
          org.apache.lucene.analysis.TokenFilter
              org.apache.lucene.facet.index.streaming.CategoryTokenizerBase

All Implemented Interfaces:

Closeable

Direct Known Subclasses:

CategoryListTokenizer, CategoryTokenizer

public abstract class CategoryTokenizerBase
extends TokenFilter

A base class for all token filters which add term and payload attributes to tokens and are to be used in CategoryDocumentBuilder. Contains three attributes: CategoryAttribute, CharTermAttribute and PayloadAttribute.

WARNING: This API is experimental and might change in incompatible ways in the next release.

Nested Class Summary

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

AttributeSource.AttributeFactory, AttributeSource.State

Field Summary

protected CategoryAttribute	categoryAttribute The stream's category attributes.
protected FacetIndexingParams	indexingParams Indexing params for creating term text
protected Payload	payload The object used for constructing payloads.
protected PayloadAttribute	payloadAttribute The stream's payload attribute.
protected CharTermAttribute	termAttribute The stream's term attribute.

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

input

Constructor Summary

CategoryTokenizerBase(TokenStream input, FacetIndexingParams indexingParams)
Constructor.

Method Summary

abstract boolean

incrementToken() Consumers (i.e., IndexWriter) use this method to advance the stream to the next token.

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, equals, getAttribute, getAttributeClassesIterator, getAttributeFactory, getAttributeImplsIterator, hasAttribute, hasAttributes, hashCode, reflectAsString, reflectWith, restoreState, toString

Methods inherited from class java.lang.Object

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

Field Detail

categoryAttribute

protected CategoryAttribute categoryAttribute

The stream's category attributes.

payloadAttribute

protected PayloadAttribute payloadAttribute

The stream's payload attribute.

termAttribute

protected CharTermAttribute termAttribute

The stream's term attribute.

payload

protected Payload payload

The object used for constructing payloads.

indexingParams

protected FacetIndexingParams indexingParams

Indexing params for creating term text

Constructor Detail

CategoryTokenizerBase

public CategoryTokenizerBase(TokenStream input,
                             FacetIndexingParams indexingParams)

Constructor.

Parameters:

input - The input stream, either CategoryParentsStream or an extension of CategoryTokenizerBase.

indexingParams - The indexing params to use.

Method Detail

incrementToken

public abstract boolean incrementToken()
                                throws 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:

IOException