Class CategoryTokenizerBase

  extended by org.apache.lucene.util.AttributeSource
      extended by org.apache.lucene.analysis.TokenStream
          extended by org.apache.lucene.analysis.TokenFilter
              extended by org.apache.lucene.facet.index.streaming.CategoryTokenizerBase
All Implemented Interfaces:
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
Constructor Summary
CategoryTokenizerBase(TokenStream input, FacetIndexingParams indexingParams)
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


protected CategoryAttribute categoryAttribute
The stream's category attributes.


protected PayloadAttribute payloadAttribute
The stream's payload attribute.


protected CharTermAttribute termAttribute
The stream's term attribute.


protected Payload payload
The object used for constructing payloads.


protected FacetIndexingParams indexingParams
Indexing params for creating term text

Constructor Detail


public CategoryTokenizerBase(TokenStream input,
                             FacetIndexingParams indexingParams)

input - The input stream, either CategoryParentsStream or an extension of CategoryTokenizerBase.
indexingParams - The indexing params to use.
Method Detail


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
false for end of stream; true otherwise

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