Package org.apache.lucene.analysis.miscellaneous

Class ScandinavianNormalizationFilter

java.lang.Object

org.apache.lucene.util.AttributeSource

org.apache.lucene.analysis.TokenStream

org.apache.lucene.analysis.TokenFilter

org.apache.lucene.analysis.miscellaneous.ScandinavianNormalizationFilter

All Implemented Interfaces:

Closeable, AutoCloseable, Unwrappable<TokenStream>

public final class ScandinavianNormalizationFilter
extends TokenFilter

This filter normalize use of the interchangeable Scandinavian characters æÆäÄöÖøØ and folded variants (aa, ao, ae, oe and oo) by transforming them to åÅæÆøØ.

It's a semantically less destructive solution than ScandinavianFoldingFilter, most useful when a person with a Norwegian or Danish keyboard queries a Swedish index and vice versa. This filter does not the common Swedish folds of å and ä to a nor ö to o.

blåbærsyltetøj == blåbärsyltetöj == blaabaarsyltetoej but not blabarsyltetoj räksmörgås == ræksmørgås == ræksmörgaos == raeksmoergaas but not raksmorgas

There are also separate filters for Norwegian, Danish and Swedish with slightly differing settings

See Also:

• ScandinavianFoldingFilter

Nested Class Summary

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

AttributeSource.State

Field Summary

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

input

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

DEFAULT_TOKEN_ATTRIBUTE_FACTORY

Constructor Summary

Constructors

Constructor	Description
ScandinavianNormalizationFilter(TokenStream input)

Method Summary

Modifier and Type	Method	Description
boolean	incrementToken()

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

close, end, reset, unwrap

Methods inherited from class org.apache.lucene.util.AttributeSource

addAttribute, addAttributeImpl, captureState, clearAttributes, cloneAttributes, copyTo, endAttributes, equals, getAttribute, getAttributeClassesIterator, getAttributeFactory, getAttributeImplsIterator, hasAttribute, hasAttributes, hashCode, reflectAsString, reflectWith, removeAllAttributes, restoreState, toString

Methods inherited from class java.lang.Object

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

Constructor Details

ScandinavianNormalizationFilter

public ScandinavianNormalizationFilter(TokenStream input)

Method Details

incrementToken

public boolean incrementToken()
                       throws IOException

Specified by:

incrementToken in class TokenStream

Throws:

IOException