C# Class Lucene.Net.Analysis.Pattern.PatternCaptureGroupTokenFilter

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

Inheritance: TokenFilter
Datei anzeigen Open project: apache/lucenenet Class Usage Examples

Public Methods

Method Description
IncrementToken ( ) : bool
PatternCaptureGroupTokenFilter ( TokenStream input, bool preserveOriginal ) : Lucene.Net.Analysis.Tokenattributes
Reset ( ) : void

Private Methods

Method Description
NextCapture ( ) : bool

Method Details

IncrementToken() public method

public IncrementToken ( ) : bool
return bool

PatternCaptureGroupTokenFilter() public method

public PatternCaptureGroupTokenFilter ( TokenStream input, bool preserveOriginal ) : Lucene.Net.Analysis.Tokenattributes
input TokenStream /// the input
preserveOriginal bool /// set to true to return the original token even if one of the /// patterns matches
return Lucene.Net.Analysis.Tokenattributes

Reset() public method

public Reset ( ) : void
return void