public final class PatternCaptureGroupTokenFilter extends TokenFilterCaptureGroup uses Java regexes to emit multiple tokens - one for each capture group in one or more patterns.
For example, a pattern like:
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
A camelCaseFilter could be written as:
preserveOriginalis true, it would also return
All Methods Instance Methods Concrete Methods Modifier and Type Method Description
IndexWriter) use this method to advance the stream to the next token.
reset()This method is called by a consumer before it begins consumption using
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, toString
public PatternCaptureGroupTokenFilter(TokenStream input, boolean preserveOriginal, Pattern... patterns)
public boolean incrementToken() throws IOExceptionDescription copied from class:
IndexWriter) use this method to advance the stream to the next token. Implementing classes must implement this method and update the appropriate
AttributeImpls with the attributes of the next token.
The producer must make no assumptions about the attributes after the method has been returned: the caller may arbitrarily change it. If the producer needs to preserve the state for subsequent calls, it can use
AttributeSource.captureState()to create a copy of the current attribute state.
This method is called for every token of a document, so an efficient implementation is crucial for good performance. To avoid calls to
AttributeSource.getAttribute(Class), references to all
AttributeImpls that this stream uses should be retrieved during instantiation.
To ensure that filters and consumers know which attributes are available, the attributes must be added during instantiation. Filters and consumers are not required to check for availability of attributes in
public void reset() throws IOExceptionDescription copied from class:
TokenFilterThis method is called by a consumer before it begins consumption using
Resets this stream to a clean state. Stateful implementations must implement this method so that they can be reused, just as if they had been created fresh.
NOTE: The default implementation chains the call to the input TokenStream, so be sure to call
super.reset()when overriding this method.