org.apache.lucene.analysis.el
Class GreekLowerCaseFilter

java.lang.Object
  org.apache.lucene.util.AttributeSource
      org.apache.lucene.analysis.TokenStream
          org.apache.lucene.analysis.TokenFilter
              org.apache.lucene.analysis.el.GreekLowerCaseFilter

All Implemented Interfaces:

Closeable

public final class GreekLowerCaseFilter
extends TokenFilter

Normalizes token text to lower case, removes some Greek diacritics, and standardizes final sigma to sigma.

You must specify the required Version compatibility when creating GreekLowerCaseFilter:

• As of 3.1, supplementary characters are properly lowercased.

Nested Class Summary

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

AttributeSource.AttributeFactory, AttributeSource.State

Field Summary

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

input

Constructor Summary

GreekLowerCaseFilter(TokenStream in)
Deprecated. Use GreekLowerCaseFilter(Version, TokenStream) instead.

GreekLowerCaseFilter(Version matchVersion, TokenStream in)
Create a GreekLowerCaseFilter that normalizes Greek token text.

Method Summary

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

Constructor Detail

GreekLowerCaseFilter

@Deprecated
public GreekLowerCaseFilter(TokenStream in)

Deprecated. Use GreekLowerCaseFilter(Version, TokenStream) instead.

GreekLowerCaseFilter

public GreekLowerCaseFilter(Version matchVersion,
                            TokenStream in)

Create a GreekLowerCaseFilter that normalizes Greek token text.

Parameters:

matchVersion - Lucene compatibility version, See above

in - TokenStream to filter

Method Detail

incrementToken

public 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