public class CategoryAttributesStream extends TokenStream
Iterable of
CategoryAttribute. This stream should then be passed through several
filters (see CategoryParentsStream, CategoryListTokenizer and
CategoryTokenizer) until a token stream is produced that can be
indexed by Lucene.
A CategoryAttributesStream object can be reused for producing more than one
stream. To do that, the user should cause the underlying
Iterablereset() to allow this stream to be used again.
AttributeSource.AttributeFactory, AttributeSource.State| Modifier and Type | Field and Description |
|---|---|
protected CategoryAttribute |
categoryAttribute |
| Constructor and Description |
|---|
CategoryAttributesStream(Iterable<CategoryAttribute> iterable)
Constructor
|
| Modifier and Type | Method and Description |
|---|---|
boolean |
incrementToken()
Consumers (i.e.,
IndexWriter) use this method to advance the stream to
the next token. |
void |
reset()
Resets this stream to the beginning.
|
close, endaddAttribute, addAttributeImpl, captureState, clearAttributes, cloneAttributes, copyTo, equals, getAttribute, getAttributeClassesIterator, getAttributeFactory, getAttributeImplsIterator, hasAttribute, hasAttributes, hashCode, reflectAsString, reflectWith, restoreState, toStringprotected CategoryAttribute categoryAttribute
public CategoryAttributesStream(Iterable<CategoryAttribute> iterable)
iterable - Iterable of CategoryAttribute, from which
categories are taken.public final boolean incrementToken()
throws IOException
TokenStreamIndexWriter) 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().
incrementToken in class TokenStreamIOExceptionpublic void reset()
TokenStreamTokenStream.reset() is not needed for
the standard indexing process. However, if the tokens of a
TokenStream are intended to be consumed more than once, it is
necessary to implement TokenStream.reset(). Note that if your TokenStream
caches tokens and feeds them back again after a reset, it is imperative
that you clone the tokens when you store them away (on the first pass) as
well as when you return them (on future passes after TokenStream.reset()).reset in class TokenStream