Class ScandinavianNormalizationFilter

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

Constructors

ScandinavianNormalizationFilter(TokenStream)

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
Declaration
public ScandinavianNormalizationFilter(TokenStream input)
Parameters
Type Name Description
TokenStream input
See Also

Methods

IncrementToken()

Consumers (i.e., Lucene.Net.Index.IndexWriter) use this method to advance the stream to the next token. Implementing classes must implement this method and update the appropriate Lucene.Net.Util.IAttributes 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 Lucene.Net.Util.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 Lucene.Net.Util.AttributeSource.AddAttribute<T>() and Lucene.Net.Util.AttributeSource.GetAttribute<T>(), references to all Lucene.Net.Util.IAttributes 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 Lucene.Net.Analysis.TokenStream.IncrementToken().
Declaration
public override bool IncrementToken()
Returns
Type Description
bool

false for end of stream; true otherwise
Overrides
Lucene.Net.Analysis.TokenStream.IncrementToken()
See Also

Implements

See Also