CleartkExtractor (ClearTK TimeML 2.0.0 API)

java.lang.Object
- org.cleartk.ml.feature.extractor.CleartkExtractor<FOCUS_T,SEARCH_T>

All Implemented Interfaces:

FeatureExtractor1<FOCUS_T>, FeatureExtractor2<FOCUS_T,FOCUS_T>
```
public class CleartkExtractor<FOCUS_T extends Annotation,SEARCH_T extends Annotation>
extends Object
implements FeatureExtractor1<FOCUS_T>, FeatureExtractor2<FOCUS_T,FOCUS_T>
```
A feature extractor that finds other Annotations in the context of a focus annotation and extracts features from these. It can be used, for example, to:
- Get the text of the 2 tokens before a focus annotation
- Get the parts of speech of the 3 tokens after a focus annotation
- Get the tokens after a focus annotation, beginning 2 after and ending 5 after, as a bag of words
- Get an ngram concatenating the stem of the first word before a focus annotation and the first word contained in the focus annotation
Copyright (c) 2011, Regents of the University of Colorado
All rights reserved.
Author:

Steven Bethard

Nested Class Summary

Nested Classes
Modifier and Type	Class and Description
`static class`	`CleartkExtractor.Bag` A `CleartkExtractor.Context` that aggregates the features of other contexts into a "bag" where position information of each individual feature is no longer maintained.
`static interface`	`CleartkExtractor.Bounds` A class representing the bounds within which a `CleartkExtractor` should look for annotations.
`static interface`	`CleartkExtractor.Context` A class representing a location that a `CleartkExtractor` should look for annotations.
`static class`	`CleartkExtractor.Count` A `CleartkExtractor.Context` that aggregates the features of other contexts into a bag of counts where only the count of occurrence of each feature value is maintained.
`static class`	`CleartkExtractor.Covered` A `CleartkExtractor.Context` for extracting all annotations within the focus annotation.
`static class`	`CleartkExtractor.FirstCovered` A `CleartkExtractor.Context` for extracting the first annotations within the focus annotation.
`static class`	`CleartkExtractor.Focus` A `CleartkExtractor.Context` for extracting the focus annotation.
`static class`	`CleartkExtractor.Following` A `CleartkExtractor.Context` for extracting annotations appearing after the focus annotation.
`static class`	`CleartkExtractor.LastCovered` A `CleartkExtractor.Context` for extracting the last annotations within the focus annotation.
`static class`	`CleartkExtractor.NestedCountFeature`
`static class`	`CleartkExtractor.Ngram` A `CleartkExtractor.Context` that aggregates the features of other contexts into a single "ngram" feature, where the feature values are concatenated together in order to form a single value.
`static class`	`CleartkExtractor.Ngrams` A `CleartkExtractor.Context` that aggregates the features of other contexts into several "ngrams" features, where sub-sequences of the feature values are concatenated together in order to form single values.
`static class`	`CleartkExtractor.Preceding` A `CleartkExtractor.Context` for extracting annotations appearing before the focus annotation.

Constructor Summary

Constructors
Constructor and Description
`CleartkExtractor(Class<SEARCH_T> annotationClass, FeatureExtractor1<SEARCH_T> extractor, CleartkExtractor.Context... contexts)` Create an extractor that finds `Annotation`s of the given type at the specified `CleartkExtractor.Context`s and applies the given feature extractor to the annotations.

Method Summary

Methods
Modifier and Type	Method and Description
`List<Feature>`	`extract(JCas view, FOCUS_T focusAnnotation)` Some feature extractors will require some specific number of annotations that is greater than one.
`List<Feature>`	`extract(JCas view, FOCUS_T annotation1, FOCUS_T annotation2)`
`List<Feature>`	`extractBetween(JCas view, FOCUS_T annotation1, FOCUS_T annotation2)`
`List<Feature>`	`extractWithin(JCas view, FOCUS_T focusAnnotation, Annotation boundsAnnotation)` Extract features from the annotations around the focus annotation and within the given bounds.

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

- Constructor Detail
  - CleartkExtractor
```
public CleartkExtractor(Class<SEARCH_T> annotationClass,
                FeatureExtractor1<SEARCH_T> extractor,
                CleartkExtractor.Context... contexts)
```
    Create an extractor that finds Annotations of the given type at the specified CleartkExtractor.Contexts and applies the given feature extractor to the annotations.
    
    Parameters:
    annotationClass - The type of annotation which should be searched for in the context.
    extractor - The feature extractor to apply to each annotation found.
    contexts - The contexts where the extractor should look for annotations.
- Method Detail
  - extract
```
public List<Feature> extract(JCas view,
                    FOCUS_T focusAnnotation)
                      throws CleartkExtractorException
```
    Description copied from interface: FeatureExtractor1
    
    Some feature extractors will require some specific number of annotations that is greater than one. Such extractors should not implement this interface.
    
    Specified by:
    
    extract in interface FeatureExtractor1<FOCUS_T extends Annotation>
    
    Parameters:
    view - the current view of the document.
    focusAnnotation - the annotation for which to collect features.
    
    Returns:
    a list of features generated by the extractor for the focus annotation.
    
    Throws:
    
    CleartkExtractorException
  - extract
```
public List<Feature> extract(JCas view,
                    FOCUS_T annotation1,
                    FOCUS_T annotation2)
                      throws CleartkExtractorException
```
    Specified by:
    
    extract in interface FeatureExtractor2<FOCUS_T extends Annotation,FOCUS_T extends Annotation>
    
    Throws:
    
    CleartkExtractorException
  - extractBetween
```
public List<Feature> extractBetween(JCas view,
                           FOCUS_T annotation1,
                           FOCUS_T annotation2)
                             throws CleartkExtractorException
```
    Throws:
    
    CleartkExtractorException
  - extractWithin
```
public List<Feature> extractWithin(JCas view,
                          FOCUS_T focusAnnotation,
                          Annotation boundsAnnotation)
                            throws CleartkExtractorException
```
    Extract features from the annotations around the focus annotation and within the given bounds.
    
    Parameters:
    view - The JCas containing the focus annotation.
    focusAnnotation - The annotation whose context is to be searched.
    boundsAnnotation - The boundary within which context annotations may be identified.
    
    Returns:
    The features extracted in the context of the focus annotation.
    
    Throws:
    
    CleartkExtractorException

Class CleartkExtractor<FOCUS_T extends Annotation,SEARCH_T extends Annotation>

Nested Class Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Constructor Detail

CleartkExtractor

Method Detail

extract

extract

extractBetween

extractWithin