gate.creole.ml
Class MachineLearningPR.Cache

java.lang.Object
  gate.creole.ml.MachineLearningPR.Cache

Enclosing class:

MachineLearningPR

protected class MachineLearningPR.Cache
extends Object

Field Summary

protected List	backwardCache Stores cached data with attribute values for instances placed before the current instance.
protected Map	currentAttributes A Map with annotationTypes as keys.
protected List	forwardCache Stores cached data with attribute values for instances placed after the current instance.

Constructor Summary

MachineLearningPR.Cache()

Method Summary

String	getAttributeValue(int instanceIndex, Attribute attribute) Finds the value of a specified attribute for a particular instance.
protected String	getValue(Attribute attribute, int instanceIndex, Map cache) Finds the value for a particular attribute and returns it.
void	shift() Notifies the cache that it should advance its internal structures one step forward.

Methods inherited from class java.lang.Object

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

Field Detail

forwardCache

protected List forwardCache

Stores cached data with attribute values for instances placed after the current instance. For each instance (i.e. for each position in the list) the data is a Map with annotationTypes as keys. For each annotation type the data stored is another Map with feature names as keys and feature values as values. The null key is used for a boolean value (stored as one of the "true" or "false" strings) signifying the presence (or lack of presence) of the required type of annotation at the location. forwardCache[2].get("Lookup").get(null) == "false" means that no lookup annotation covers the second instance to the right from the current instance.

backwardCache

protected List backwardCache

Stores cached data with attribute values for instances placed before the current instance. For each instance (i.e. for each position in the list) the data is a Map with annotationTypes as keys. For each annotation type the data stored is another Map with feature names as keys and feature values as values. The null key is used for a boolean value (stored as one of the "true" or "false" strings) signifying the presence (or lack of presence) of the required type of annotation at the location. backwardCache[2].get("Lookup").get(null) == "false" means that no lookup annotation covers the second instance to the left from the current instance.

currentAttributes

protected Map currentAttributes

A Map with annotationTypes as keys. For each annotation type the data stored is another Map with feature names as keys and feature values as values. The null key is used for a boolean value (stored as one of the "true" or "false" strings) signifying the presence (or lack of presence) of the required type of annotation at the location. currentAttributes.get(Lookup).get(null) == "false" means that the current instance is not covered by a Lookup annotation. currentAttributes.get(Lookup) == null menas nothing is known about Lookup annotations caovering the current instance.

Constructor Detail

MachineLearningPR.Cache

public MachineLearningPR.Cache()

Method Detail

getAttributeValue

public String getAttributeValue(int instanceIndex,
                                Attribute attribute)

Finds the value of a specified attribute for a particular instance.

Parameters:

instanceIndex - the index of the current instance in the annotations List.

attribute - the attribute whose value needs to be found

Returns:

a String representing the value for the attribute.

shift

public void shift()

Notifies the cache that it should advance its internal structures one step forward.

getValue

protected String getValue(Attribute attribute,
                          int instanceIndex,
                          Map cache)

Finds the value for a particular attribute and returns it. If the value is not present in the cache it will be retrieved from the document and the cache will be updated.

Parameters:

attribute - the attribute whose value is requested.

cache - the Map containing the cache for the appropriate position for the attribute

instanceIndex - the index of the instance annotation which is covered by the sought attribute

Returns:

a String value.