PatternCaptureGroupTokenFilter (Lucene 9.0.0 common API)

java.lang.Object
- org.apache.lucene.util.AttributeSource
- - org.apache.lucene.analysis.TokenStream
  - - org.apache.lucene.analysis.TokenFilter
    - - org.apache.lucene.analysis.pattern.PatternCaptureGroupTokenFilter

All Implemented Interfaces:

Closeable, AutoCloseable
```
public final class PatternCaptureGroupTokenFilter
extends TokenFilter
```
CaptureGroup uses Java regexes to emit multiple tokens - one for each capture group in one or more patterns.
For example, a pattern like:
"(https?://([a-zA-Z\-_0-9.]+))"
when matched against the string "http://www.foo.com/index" would return the tokens "https://www.foo.com" and "www.foo.com".
If none of the patterns match, or if preserveOriginal is true, the original token will be preserved.
Each pattern is matched as often as it can be, so the pattern "(...)", when matched against "abcdefghi" would produce ["abc","def","ghi"]
A camelCaseFilter could be written as:
"([A-Z]{2,})", "(?<![A-Z])([A-Z][a-z]+)", "(?:^|\\b|(?<=[0-9_])|(?<=[A-Z]{2}))([a-z]+)", "([0-9]+)"
plus if preserveOriginal is true, it would also return "camelCaseFilter"

Nested Class Summary
- Nested classes/interfaces inherited from class org.apache.lucene.util.AttributeSource
  AttributeSource.State

Field Summary
- 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	Description
`PatternCaptureGroupTokenFilter(TokenStream input, boolean preserveOriginal, Pattern... patterns)`

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type Method Description

boolean incrementToken()

void reset()
- 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

- Constructor Detail
  - PatternCaptureGroupTokenFilter
```
public PatternCaptureGroupTokenFilter(TokenStream input,
                                      boolean preserveOriginal,
                                      Pattern... patterns)
```
    Parameters:
    
    input - the input TokenStream
    
    preserveOriginal - set to true to return the original token even if one of the patterns matches
    
    patterns - an array of Pattern objects to match against each token
- Method Detail
  - incrementToken
```
public boolean incrementToken()
                       throws IOException
```
    Specified by:
    
    incrementToken in class TokenStream
    
    Throws:
    
    IOException
  - reset
```
public void reset()
           throws IOException
```
    Overrides:
    
    reset in class TokenFilter
    
    Throws:
    
    IOException