se.lth.cs.nlp.nlputils.ml
Class Classifier<ItemType>

java.lang.Object
  se.lth.cs.nlp.nlputils.ml.Classifier<ItemType>

All Implemented Interfaces:

Serializable

Direct Known Subclasses:

BinaryNumericClassifier, ClasswiseClassifier, PairwiseClassifier, ProbabilityClassifier

public abstract class Classifier<ItemType>
extends Object
implements Serializable

Abstract class representing a classifier.

Author:

Richard Johansson (richard@cs.lth.se)

See Also:

Serialized Form

Field Summary

protected FeatureExtractor<ItemType>	extractor The feature extractor that is used in classify(ItemType item).
protected FeatureList	list The feature list that is used in classify(ItemType item).

Constructor Summary

Classifier()

Method Summary

abstract Object	classify(FeatureList features) Performs a classification given a feature list.
Object	classify(ItemType item) Auxiliary method that calls the feature extractor on the item.
Object	classifyRestricted(FeatureList features, Collection classes) Optional method that makes sure that restricts the range of the output value.
void	setFeatureExtractor(FeatureExtractor<ItemType> extractor, FeatureList list) Sets the feature extractor of this classifier.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

extractor

protected FeatureExtractor<ItemType> extractor

The feature extractor that is used in classify(ItemType item).

list

protected FeatureList list

The feature list that is used in classify(ItemType item).

Constructor Detail

Classifier

public Classifier()

Method Detail

classify

public Object classify(ItemType item)

Auxiliary method that calls the feature extractor on the item.

Parameters:

item - the item to classify.

Returns:

the result of the classification, or null if the feature extraction did not return FEATURE_EXTRACTOR_OK.

classify

public abstract Object classify(FeatureList features)

Performs a classification given a feature list.

Parameters:

features - the feature list.

Returns:

the result of the classification.

setFeatureExtractor

public void setFeatureExtractor(FeatureExtractor<ItemType> extractor,
                                FeatureList list)

Sets the feature extractor of this classifier.

Parameters:

extractor - the feature extractor.

classifyRestricted

public Object classifyRestricted(FeatureList features,
                                 Collection classes)

Optional method that makes sure that restricts the range of the output value.

Parameters:

features - the feature list.

classes - a collection of allowed classes.

Returns:

the result of the classification.

Throws:

UnsupportedOperationException - if the method is not implemented.