Class ChineseFilter

A Lucene.Net.Analysis.TokenFilter with a stop word table.

  • Numeric tokens are removed.
  • English tokens must be larger than 1 character.
  • One Chinese character as one Chinese word.
TO DO:
  1. Add Chinese stop words, such as \ue400
  2. Dictionary based Chinese word extraction
  3. Intelligent Chinese word extraction
Inheritance
object
AttributeSource
TokenStream
TokenFilter
ChineseFilter
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.Cn
Assembly: Lucene.Net.Analysis.Common.dll
Syntax
[Obsolete("(3.1) Use StopFilter instead, which has the same functionality.")]
public sealed class ChineseFilter : TokenFilter, IDisposable

Constructors

ChineseFilter(TokenStream)

A Lucene.Net.Analysis.TokenFilter with a stop word table.

  • Numeric tokens are removed.
  • English tokens must be larger than 1 character.
  • One Chinese character as one Chinese word.
TO DO:
  1. Add Chinese stop words, such as \ue400
  2. Dictionary based Chinese word extraction
  3. Intelligent Chinese word extraction
Declaration
public ChineseFilter(TokenStream @in)
Parameters
Type Name Description
TokenStream in

Fields

STOP_WORDS

A Lucene.Net.Analysis.TokenFilter with a stop word table.

  • Numeric tokens are removed.
  • English tokens must be larger than 1 character.
  • One Chinese character as one Chinese word.
TO DO:
  1. Add Chinese stop words, such as \ue400
  2. Dictionary based Chinese word extraction
  3. Intelligent Chinese word extraction
Declaration
public static readonly string[] STOP_WORDS
Field Value
Type Description
string[]

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()

Implements