SynonymTokenFilter (Lucene 2.9.4 API)

java.lang.Object
- org.apache.lucene.util.AttributeSource
- - org.apache.lucene.analysis.TokenStream
  - - org.apache.lucene.analysis.TokenFilter
    - - org.apache.lucene.index.memory.SynonymTokenFilter

```
public class SynonymTokenFilter
extends TokenFilter
```
Injects additional tokens for synonyms of token terms fetched from the underlying child stream; the child stream must deliver lowercase tokens for synonyms to be found.

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 java.lang.String SYNONYM_TOKEN_TYPE
The Token.type used to indicate a synonym to higher level filters.
- Fields inherited from class org.apache.lucene.analysis.TokenFilter
  input

Fields
Modifier and Type	Field and Description
`static java.lang.String`	`SYNONYM_TOKEN_TYPE` The Token.type used to indicate a synonym to higher level filters.

Constructor Summary

Constructors
Constructor and Description
`SynonymTokenFilter(TokenStream input, SynonymMap synonyms, int maxSynonyms)` Creates an instance for the given underlying stream and synonym table.

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`protected boolean`	`createToken(java.lang.String synonym, AttributeSource.State current)` Creates and returns a token for the given synonym of the current input token; Override for custom (stateless or stateful) behavior, if desired.
`boolean`	`incrementToken()` Returns the next token in the stream, or null at EOS.
`void`	`reset()` Reset the filter as well as the input TokenStream.

Methods inherited from class org.apache.lucene.analysis.TokenFilter
close, end

Methods inherited from class org.apache.lucene.analysis.TokenStream
getOnlyUseNewAPI, next, next, setOnlyUseNewAPI

Methods inherited from class org.apache.lucene.util.AttributeSource
addAttribute, addAttributeImpl, captureState, clearAttributes, cloneAttributes, equals, getAttribute, getAttributeClassesIterator, getAttributeFactory, getAttributeImplsIterator, hasAttribute, hasAttributes, hashCode, restoreState, toString

Methods inherited from class java.lang.Object
clone, finalize, getClass, notify, notifyAll, wait, wait, wait

- Field Detail
  - SYNONYM_TOKEN_TYPE
```
public static final java.lang.String SYNONYM_TOKEN_TYPE
```
    The Token.type used to indicate a synonym to higher level filters.
    
    See Also:
    
    Constant Field Values
- Constructor Detail
  - SynonymTokenFilter
```
public SynonymTokenFilter(TokenStream input,
                          SynonymMap synonyms,
                          int maxSynonyms)
```
    Creates an instance for the given underlying stream and synonym table.
    
    Parameters:
    
    input - the underlying child token stream
    
    synonyms - the map used to extract synonyms for terms
    
    maxSynonyms - the maximum number of synonym tokens to return per underlying token word (a value of Integer.MAX_VALUE indicates unlimited)
- Method Detail
  - incrementToken
```
public final boolean incrementToken()
                             throws java.io.IOException
```
    Returns the next token in the stream, or null at EOS.
    
    Overrides:
    
    incrementToken in class TokenStream
    
    Returns:
    
    false for end of stream; true otherwise
    Note that this method will be defined abstract in Lucene 3.0.
    
    Throws:
    
    java.io.IOException
  - createToken
```
protected boolean createToken(java.lang.String synonym,
                              AttributeSource.State current)
```
    Creates and returns a token for the given synonym of the current input token; Override for custom (stateless or stateful) behavior, if desired.
    
    Parameters:
    
    synonym - a synonym for the current token's term
    
    current - the current token from the underlying child stream
    
    Returns:
    
    a new token, or null to indicate that the given synonym should be ignored
  - reset
```
public void reset()
           throws java.io.IOException
```
    Description copied from class: TokenFilter
    
    Reset the filter as well as the input TokenStream.
    
    Overrides:
    
    reset in class TokenFilter
    
    Throws:
    
    java.io.IOException

Class SynonymTokenFilter

Nested Class Summary

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

Field Summary

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

Constructor Summary

Method Summary

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

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

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

Methods inherited from class java.lang.Object

Field Detail

SYNONYM_TOKEN_TYPE

Constructor Detail

SynonymTokenFilter

Method Detail

incrementToken

createToken

reset