Class ScandinavianFoldingFilter

This filter folds Scandinavian characters åÅäæÄÆ->a and öÖøØ->o. It also discriminate against use of double vowels aa, ae, ao, oe and oo, leaving just the first one.

It's is a semantically more destructive solution than ScandinavianNormalizationFilter but can in addition help with matching raksmorgas as räksmörgås.

blåbærsyltetøj == blåbärsyltetöj == blaabaarsyltetoej == blabarsyltetoj räksmörgås == ræksmørgås == ræksmörgaos == raeksmoergaas == raksmorgas

Background: Swedish åäö are in fact the same letters as Norwegian and Danish åæø and thus interchangeable when used between these languages. They are however folded differently when people type them on a keyboard lacking these characters.

In that situation almost all Swedish people use a, a, o instead of å, ä, ö.

Norwegians and Danes on the other hand usually type aa, ae and oe instead of å, æ and ø. Some do however use a, a, o, oo, ao and sometimes permutations of everything above.

This filter solves that mismatch problem, but might also cause new.

Inheritance
System.Object
Lucene.Net.Util.AttributeSource
Lucene.Net.Analysis.TokenStream
Lucene.Net.Analysis.TokenFilter
ScandinavianFoldingFilter
Implements
System.IDisposable
Inherited Members
Lucene.Net.Analysis.TokenFilter.m_input
Lucene.Net.Analysis.TokenFilter.End()
Lucene.Net.Analysis.TokenFilter.Reset()
Lucene.Net.Analysis.TokenStream.Dispose()
Lucene.Net.Util.AttributeSource.GetAttributeFactory()
Lucene.Net.Util.AttributeSource.GetAttributeClassesEnumerator()
Lucene.Net.Util.AttributeSource.GetAttributeImplsEnumerator()
Lucene.Net.Util.AttributeSource.AddAttributeImpl(Lucene.Net.Util.Attribute)
Lucene.Net.Util.AttributeSource.AddAttribute<T>()
Lucene.Net.Util.AttributeSource.HasAttributes
Lucene.Net.Util.AttributeSource.HasAttribute<T>()
Lucene.Net.Util.AttributeSource.GetAttribute<T>()
Lucene.Net.Util.AttributeSource.ClearAttributes()
Lucene.Net.Util.AttributeSource.CaptureState()
Lucene.Net.Util.AttributeSource.RestoreState(Lucene.Net.Util.AttributeSource.State)
Lucene.Net.Util.AttributeSource.GetHashCode()
Lucene.Net.Util.AttributeSource.ReflectWith(Lucene.Net.Util.IAttributeReflector)
Lucene.Net.Util.AttributeSource.CloneAttributes()
Lucene.Net.Util.AttributeSource.CopyTo(Lucene.Net.Util.AttributeSource)
Lucene.Net.Util.AttributeSource.ToString()
System.Object.Equals(System.Object, System.Object)
System.Object.GetType()
System.Object.MemberwiseClone()
System.Object.ReferenceEquals(System.Object, System.Object)
Namespace: Lucene.Net.Analysis.Miscellaneous
Assembly: Lucene.Net.Analysis.Common.dll
Syntax
public sealed class ScandinavianFoldingFilter : TokenFilter, IDisposable

Constructors

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ScandinavianFoldingFilter(TokenStream)

Declaration
public ScandinavianFoldingFilter(TokenStream input)
Parameters
Type Name Description
Lucene.Net.Analysis.TokenStream input

Methods

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IncrementToken()

Declaration
public override bool IncrementToken()
Returns
Type Description
System.Boolean
Overrides
Lucene.Net.Analysis.TokenStream.IncrementToken()

Implements

System.IDisposable

See Also