org.apache.lucene.analysis.standard

Class ClassicTokenizer

java.lang.Object

org.apache.lucene.util.AttributeSource

org.apache.lucene.analysis.TokenStream

org.apache.lucene.analysis.Tokenizer

org.apache.lucene.analysis.standard.ClassicTokenizer

All Implemented Interfaces:

Closeable

public final class ClassicTokenizer
extends Tokenizer

A grammar-based tokenizer constructed with JFlex

This should be a good tokenizer for most European-language documents:

• Splits words at punctuation characters, removing punctuation. However, a dot that's not followed by whitespace is considered part of a token.
• Splits words at hyphens, unless there's a number in the token, in which case the whole token is interpreted as a product number and is not split.
• Recognizes email addresses and internet hostnames as one token.

Many applications have specific tokenizer needs. If this tokenizer does not suit your application, please consider copying this source code directory to your project and maintaining your own grammar-based tokenizer. ClassicTokenizer was named StandardTokenizer in Lucene versions prior to 3.1. As of 3.1, StandardTokenizer implements Unicode text segmentation, as specified by UAX#29.

Nested Class Summary

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

AttributeSource.AttributeFactory, AttributeSource.State

Field Summary

Fields

Modifier and Type	Field and Description
static int	ACRONYM
static int	ACRONYM_DEP
static int	ALPHANUM
static int	APOSTROPHE
static int	CJ
static int	COMPANY
static int	EMAIL
static int	HOST
static int	NUM
static String[]	TOKEN_TYPES String token types that correspond to token type int constants

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

input

Constructor Summary

Constructors

Constructor and Description
ClassicTokenizer(Version matchVersion, AttributeSource.AttributeFactory factory, Reader input) Creates a new ClassicTokenizer with a given AttributeSource.AttributeFactory
ClassicTokenizer(Version matchVersion, Reader input) Creates a new instance of the ClassicTokenizer.

Method Summary

Methods

Modifier and Type	Method and Description
void	end()
int	getMaxTokenLength()
boolean	incrementToken()
void	reset()
void	setMaxTokenLength(int length) Set the max allowed token length.

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

close, correctOffset, setReader

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

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

Methods inherited from class java.lang.Object

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

Field Detail

ALPHANUM

public static final int ALPHANUM

See Also:

Constant Field Values

APOSTROPHE

public static final int APOSTROPHE

See Also:

Constant Field Values

ACRONYM

public static final int ACRONYM

See Also:

Constant Field Values

COMPANY

public static final int COMPANY

See Also:

Constant Field Values

EMAIL

public static final int EMAIL

See Also:

Constant Field Values

HOST

public static final int HOST

See Also:

Constant Field Values

NUM

public static final int NUM

See Also:

Constant Field Values

CJ

public static final int CJ

See Also:

Constant Field Values

ACRONYM_DEP

public static final int ACRONYM_DEP

See Also:

Constant Field Values

TOKEN_TYPES

public static final String[] TOKEN_TYPES

String token types that correspond to token type int constants

Constructor Detail

ClassicTokenizer

public ClassicTokenizer(Version matchVersion,
                Reader input)

Creates a new instance of the ClassicTokenizer. Attaches the input to the newly created JFlex scanner.

Parameters:

input - The input reader See http://issues.apache.org/jira/browse/LUCENE-1068

ClassicTokenizer

public ClassicTokenizer(Version matchVersion,
                AttributeSource.AttributeFactory factory,
                Reader input)

Creates a new ClassicTokenizer with a given AttributeSource.AttributeFactory

Method Detail

setMaxTokenLength

public void setMaxTokenLength(int length)

Set the max allowed token length. Any token longer than this is skipped.

getMaxTokenLength

public int getMaxTokenLength()

See Also:

setMaxTokenLength(int)

incrementToken

public final boolean incrementToken()
                             throws IOException

Specified by:

incrementToken in class TokenStream

Throws:

IOException

end

public final void end()

Overrides:

end in class TokenStream

reset

public void reset()
           throws IOException

Overrides:

reset in class TokenStream

Throws:

IOException