public final class TurkishLowerCaseFilter extends TokenFilter
Turkish and Azeri have unique casing behavior for some characters. This filter applies Turkish lowercase rules. For more information, see http://en.wikipedia.org/wiki/Turkish_dotted_and_dotless_I
AttributeSource.State
Modifier and Type | Field and Description |
---|---|
private static int |
COMBINING_DOT_ABOVE |
private static int |
LATIN_CAPITAL_LETTER_I |
private static int |
LATIN_SMALL_LETTER_DOTLESS_I |
private static int |
LATIN_SMALL_LETTER_I |
private CharTermAttribute |
termAtt |
input
DEFAULT_TOKEN_ATTRIBUTE_FACTORY
Constructor and Description |
---|
TurkishLowerCaseFilter(TokenStream in)
Create a new TurkishLowerCaseFilter, that normalizes Turkish token text
to lower case.
|
Modifier and Type | Method and Description |
---|---|
private int |
delete(char[] s,
int pos,
int len)
delete a character in-place.
|
boolean |
incrementToken()
Consumers (i.e.,
IndexWriter ) use this method to advance the stream to
the next token. |
private boolean |
isBeforeDot(char[] s,
int pos,
int len)
lookahead for a combining dot above.
|
close, end, reset
addAttribute, addAttributeImpl, captureState, clearAttributes, cloneAttributes, copyTo, endAttributes, equals, getAttribute, getAttributeClassesIterator, getAttributeFactory, getAttributeImplsIterator, hasAttribute, hasAttributes, hashCode, reflectAsString, reflectWith, removeAllAttributes, restoreState, toString
private static final int LATIN_CAPITAL_LETTER_I
private static final int LATIN_SMALL_LETTER_I
private static final int LATIN_SMALL_LETTER_DOTLESS_I
private static final int COMBINING_DOT_ABOVE
private final CharTermAttribute termAtt
public TurkishLowerCaseFilter(TokenStream in)
in
- TokenStream to filterpublic final boolean incrementToken() throws java.io.IOException
TokenStream
IndexWriter
) use this method to advance the stream to
the next token. Implementing classes must implement this method and update
the appropriate AttributeImpl
s 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 AttributeImpl
s 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 TokenStream
java.io.IOException
private boolean isBeforeDot(char[] s, int pos, int len)
private int delete(char[] s, int pos, int len)