org.apache.lucene.analysis.miscellaneous

Class WordDelimiterFilter

java.lang.Object

org.apache.lucene.util.AttributeSource

org.apache.lucene.analysis.TokenStream

org.apache.lucene.analysis.TokenFilter

org.apache.lucene.analysis.miscellaneous.WordDelimiterFilter

All Implemented Interfaces:

Closeable, AutoCloseable

Deprecated.

Use WordDelimiterGraphFilter instead: it produces a correct token graph so that e.g. PhraseQuery works correctly when it's used in the search time analyzer.

@Deprecated
public final class WordDelimiterFilter
extends TokenFilter

Splits words into subwords and performs optional transformations on subword groups. Words are split into subwords with the following rules:

• split on intra-word delimiters (by default, all non alpha-numeric characters): "Wi-Fi" → "Wi", "Fi"
• split on case transitions: "PowerShot" → "Power", "Shot"
• split on letter-number transitions: "SD500" → "SD", "500"
• leading and trailing intra-word delimiters on each subword are ignored: "//hello---there, 'dude'" → "hello", "there", "dude"
• trailing "'s" are removed for each subword: "O'Neil's" → "O", "Neil"
  • Note: this step isn't performed in a separate filter because of possible subword combinations.

The combinations parameter affects how subwords are combined:

• combinations="0" causes no subword combinations: "PowerShot" → 0:"Power", 1:"Shot" (0 and 1 are the token positions)
• combinations="1" means that in addition to the subwords, maximum runs of non-numeric subwords are catenated and produced at the same position of the last subword in the run:
  • "PowerShot" → 0:"Power", 1:"Shot" 1:"PowerShot"
  • "A's+B's&C's" > 0:"A", 1:"B", 2:"C", 2:"ABC"
  • "Super-Duper-XL500-42-AutoCoder!" → 0:"Super", 1:"Duper", 2:"XL", 2:"SuperDuperXL", 3:"500" 4:"42", 5:"Auto", 6:"Coder", 6:"AutoCoder"

One use for WordDelimiterFilter is to help match words with different subword delimiters. For example, if the source text contained "wi-fi" one may want "wifi" "WiFi" "wi-fi" "wi+fi" queries to all match. One way of doing so is to specify combinations="1" in the analyzer used for indexing, and combinations="0" (the default) in the analyzer used for querying. Given that the current StandardTokenizer immediately removes many intra-word delimiters, it is recommended that this filter be used after a tokenizer that does not do this (such as WhitespaceTokenizer).

Nested Class Summary

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

AttributeSource.State

Field Summary

Fields

Modifier and Type	Field and Description
static int	ALPHA Deprecated.
static int	ALPHANUM Deprecated.
static int	CATENATE_ALL Deprecated. Causes all subword parts to be catenated:
static int	CATENATE_NUMBERS Deprecated. Causes maximum runs of word parts to be catenated:
static int	CATENATE_WORDS Deprecated. Causes maximum runs of word parts to be catenated:
static int	DIGIT Deprecated.
static int	GENERATE_NUMBER_PARTS Deprecated. Causes number subwords to be generated:
static int	GENERATE_WORD_PARTS Deprecated. Causes parts of words to be generated:
static int	LOWER Deprecated.
static int	PRESERVE_ORIGINAL Deprecated. Causes original words are preserved and added to the subword list (Defaults to false)
static int	SPLIT_ON_CASE_CHANGE Deprecated. If not set, causes case changes to be ignored (subwords will only be generated given SUBWORD_DELIM tokens)
static int	SPLIT_ON_NUMERICS Deprecated. If not set, causes numeric changes to be ignored (subwords will only be generated given SUBWORD_DELIM tokens).
static int	STEM_ENGLISH_POSSESSIVE Deprecated. Causes trailing "'s" to be removed for each subword
static int	SUBWORD_DELIM Deprecated.
static int	UPPER Deprecated.

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

input

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

DEFAULT_TOKEN_ATTRIBUTE_FACTORY

Constructor Summary

Constructors

Constructor and Description
WordDelimiterFilter(TokenStream in, byte[] charTypeTable, int configurationFlags, CharArraySet protWords) Deprecated. Creates a new WordDelimiterFilter
WordDelimiterFilter(TokenStream in, int configurationFlags, CharArraySet protWords) Deprecated. Creates a new WordDelimiterFilter using WordDelimiterIterator.DEFAULT_WORD_DELIM_TABLE as its charTypeTable

Method Summary

Modifier and Type	Method and Description
boolean	incrementToken() Deprecated.
void	reset() Deprecated.

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

close, end

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

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

Methods inherited from class java.lang.Object

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

Field Detail

LOWER

public static final int LOWER

Deprecated.

See Also:

Constant Field Values

UPPER

public static final int UPPER

Deprecated.

See Also:

Constant Field Values

DIGIT

public static final int DIGIT

Deprecated.

See Also:

Constant Field Values

SUBWORD_DELIM

public static final int SUBWORD_DELIM

Deprecated.

See Also:

Constant Field Values

ALPHA

public static final int ALPHA

Deprecated.

See Also:

Constant Field Values

ALPHANUM

public static final int ALPHANUM

Deprecated.

See Also:

Constant Field Values

GENERATE_WORD_PARTS

public static final int GENERATE_WORD_PARTS

Deprecated.

Causes parts of words to be generated:

"PowerShot" => "Power" "Shot"

See Also:

Constant Field Values

GENERATE_NUMBER_PARTS

public static final int GENERATE_NUMBER_PARTS

Deprecated.

Causes number subwords to be generated:

"500-42" => "500" "42"

See Also:

Constant Field Values

CATENATE_WORDS

public static final int CATENATE_WORDS

Deprecated.

Causes maximum runs of word parts to be catenated:

"wi-fi" => "wifi"

See Also:

Constant Field Values

CATENATE_NUMBERS

public static final int CATENATE_NUMBERS

Deprecated.

Causes maximum runs of word parts to be catenated:

"500-42" => "50042"

See Also:

Constant Field Values

CATENATE_ALL

public static final int CATENATE_ALL

Deprecated.

Causes all subword parts to be catenated:

"wi-fi-4000" => "wifi4000"

See Also:

Constant Field Values

PRESERVE_ORIGINAL

public static final int PRESERVE_ORIGINAL

Deprecated.

Causes original words are preserved and added to the subword list (Defaults to false)

"500-42" => "500" "42" "500-42"

See Also:

Constant Field Values

SPLIT_ON_CASE_CHANGE

public static final int SPLIT_ON_CASE_CHANGE

Deprecated.

If not set, causes case changes to be ignored (subwords will only be generated given SUBWORD_DELIM tokens)

See Also:

Constant Field Values

SPLIT_ON_NUMERICS

public static final int SPLIT_ON_NUMERICS

Deprecated.

If not set, causes numeric changes to be ignored (subwords will only be generated given SUBWORD_DELIM tokens).

See Also:

Constant Field Values

STEM_ENGLISH_POSSESSIVE

public static final int STEM_ENGLISH_POSSESSIVE

Deprecated.

Causes trailing "'s" to be removed for each subword

"O'Neil's" => "O", "Neil"

See Also:

Constant Field Values

Constructor Detail

WordDelimiterFilter

public WordDelimiterFilter(TokenStream in,
                           byte[] charTypeTable,
                           int configurationFlags,
                           CharArraySet protWords)

Deprecated.

Creates a new WordDelimiterFilter

Parameters:

in - TokenStream to be filtered

charTypeTable - table containing character types

configurationFlags - Flags configuring the filter

protWords - If not null is the set of tokens to protect from being delimited

WordDelimiterFilter

public WordDelimiterFilter(TokenStream in,
                           int configurationFlags,
                           CharArraySet protWords)

Deprecated.

Creates a new WordDelimiterFilter using WordDelimiterIterator.DEFAULT_WORD_DELIM_TABLE as its charTypeTable

Parameters:

in - TokenStream to be filtered

configurationFlags - Flags configuring the filter

protWords - If not null is the set of tokens to protect from being delimited

Method Detail

incrementToken

public boolean incrementToken()
                       throws IOException

Deprecated.

Specified by:

incrementToken in class TokenStream

Throws:

IOException

reset

public void reset()
           throws IOException

Deprecated.

Overrides:

reset in class TokenFilter

Throws:

IOException