Class CJKTokenizer

CJKTokenizer is designed for Chinese, Japanese, and Korean languages.

The tokens returned are every two adjacent characters with overlap match.

Example: "java C1C2C3C4" will be segmented to: "java" "C1C2" "C2C3" "C3C4".

Additionally, the following is applied to Latin text (such as English):

• Text is converted to lowercase.
• Numeric digits, '+', '#', and '_' are tokenized as letters.
• Full-width forms are converted to half-width forms.

For more info on Asian language (Chinese, Japanese, and Korean) text segmentation: please search google

Inheritance

object

AttributeSource

TokenStream

Tokenizer

CJKTokenizer

Implements

IDisposable

Inherited Members

Tokenizer.SetReader(TextReader)

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.Equals(object)

AttributeSource.ReflectAsString(bool)

AttributeSource.ReflectWith(IAttributeReflector)

AttributeSource.CloneAttributes()

AttributeSource.CopyTo(AttributeSource)

AttributeSource.ToString()

object.Equals(object, object)

object.GetType()

object.ReferenceEquals(object, object)

Namespace: Lucene.Net.Analysis.Cjk

Assembly: Lucene.Net.Analysis.Common.dll

Syntax

[Obsolete("Use StandardTokenizer, CJKWidthFilter, CJKBigramFilter, and LowerCaseFilter instead.")]
public sealed class CJKTokenizer : Tokenizer, IDisposable

Constructors

CJKTokenizer(AttributeFactory, TextReader)

CJKTokenizer is designed for Chinese, Japanese, and Korean languages.

The tokens returned are every two adjacent characters with overlap match.

Example: "java C1C2C3C4" will be segmented to: "java" "C1C2" "C2C3" "C3C4".

Additionally, the following is applied to Latin text (such as English):

• Text is converted to lowercase.
• Numeric digits, '+', '#', and '_' are tokenized as letters.
• Full-width forms are converted to half-width forms.

For more info on Asian language (Chinese, Japanese, and Korean) text segmentation: please search google

Declaration

public CJKTokenizer(AttributeSource.AttributeFactory factory, TextReader @in)

Parameters

Type	Name	Description
AttributeSource.AttributeFactory	factory
TextReader	in

CJKTokenizer(TextReader)

Construct a token stream processing the given input.

Declaration

public CJKTokenizer(TextReader @in)

Parameters

Type	Name	Description
TextReader	in	I/O reader

Methods

End()

This method is called by the consumer after the last token has been consumed, after Lucene.Net.Analysis.TokenStream.IncrementToken() returned false (using the new Lucene.Net.Analysis.TokenStream API). Streams implementing the old API should upgrade to use this feature.

This method can be used to perform any end-of-stream operations, such as setting the final offset of a stream. The final offset of a stream might differ from the offset of the last token eg in case one or more whitespaces followed after the last token, but a WhitespaceTokenizer was used.

Additionally any skipped positions (such as those removed by a stopfilter) can be applied to the position increment, or any adjustment of other attributes where the end-of-stream value may be important.

If you override this method, always call base.End();.

Declaration

public override sealed void End()

Overrides

Lucene.Net.Analysis.TokenStream.End()

Exceptions

Type	Condition
IOException	If an I/O error occurs

IncrementToken()

Returns true for the next token in the stream, or false at EOS. See http://java.sun.com/j2se/1.3/docs/api/java/lang/Character.UnicodeBlock.html for detail.

Declaration

public override bool IncrementToken()

Returns

Type	Description
bool	false for end of stream, true otherwise

Overrides

Lucene.Net.Analysis.TokenStream.IncrementToken()

Exceptions

Type	Condition
IOException	when read error happened in the InputStream

Reset()

This method is called by a consumer before it begins consumption using Lucene.Net.Analysis.TokenStream.IncrementToken().

Resets this stream to a clean state. Stateful implementations must implement this method so that they can be reused, just as if they had been created fresh.

If you override this method, always call base.Reset(), otherwise some internal state will not be correctly reset (e.g., Lucene.Net.Analysis.Tokenizer will throw InvalidOperationException on further usage).

Declaration

public override void Reset()

Overrides

Lucene.Net.Analysis.Tokenizer.Reset()

Implements

IDisposable