org.apache.ctakes.chunker.ae.adjuster

Class ChunkAdjuster

java.lang.Object

JCasAnnotator_ImplBase

org.apache.ctakes.chunker.ae.adjuster.ChunkAdjuster

public class ChunkAdjuster
extends JCasAnnotator_ImplBase

UIMA annotator that uses a pattern and a rule about that pattern to adjust certain annotations. The original reason for this annotator is to extend NP annotations to include prepositional phrases so that for the pattern NP PP NP, named entities that includes a word(s) from each of those NPs is found. Searches for the pattern within each Sentence. The end offset of the first chunk in the pattern is extended to match the end offset of the last chunk in the pattern. Note the pattern is applied repeatedly so that a sentence of NP PP NP PP NP results in only the first NP being extended all the way to the last NP in that sentence. This prevents NP annotations from only partially overlapping other NP annotations. This annotator is written to be able to handle more general cases than NP PP NP.

Field Summary

Fields

Modifier and Type	Field and Description
private java.lang.String[]	chunksTypesInPattern
private int	indexOfTokenToInclude
private Logger	logger
static java.lang.String	PARAM_CHUNK_PATTERN The pattern of chunks that trigger an adjustment.
static java.lang.String	PARAM_EXTEND_TO_INCLUDE_TOKEN The index of the token (within the pattern) to extend the end offset to include.

Constructor Summary

Constructors

Constructor and Description
ChunkAdjuster()

Method Summary

Methods

Modifier and Type	Method and Description
protected void	annotateRange(JCas jcas, int rangeBegin, int rangeEnd) A utility method that annotates a given range.
protected void	annotateSentence(JCas jcas, Sentence sent)
private boolean	compareToPattern(java.util.List<Chunk> list, int i) Compares the chunks at index i to the 1st element on the pattern, i+1 to the 2nd element, etc and returns true if the chunks starting at i fit the pattern
private void	configInit() Sets configuration parameters with values from the descriptor.
static AnalysisEngineDescription	createAnnotatorDescription(java.lang.String[] chunkPattern, int patternIndex)
private static Chunk	extendChunk(Chunk chunk, int newEnd) Update the end value for the chunk to have the new value
void	initialize(UimaContext aContext) Performs initialization logic.
void	process(JCas jcas) Invokes this annotator's analysis logic.
private void	removeEnvelopedChunks(java.util.List<Chunk> list, int i) Remove from our local list of chunks the chunks that have been enveloped.

Methods inherited from class java.lang.Object

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

Field Detail

PARAM_CHUNK_PATTERN

public static final java.lang.String PARAM_CHUNK_PATTERN

The pattern of chunks that trigger an adjustment.

See Also:

Constant Field Values

chunksTypesInPattern

private java.lang.String[] chunksTypesInPattern

PARAM_EXTEND_TO_INCLUDE_TOKEN

public static final java.lang.String PARAM_EXTEND_TO_INCLUDE_TOKEN

The index of the token (within the pattern) to extend the end offset to include. E.g. is 2 to extend the first NP to include the last NP in NP PP NP.

See Also:

Constant Field Values

indexOfTokenToInclude

private int indexOfTokenToInclude

logger

private Logger logger

Constructor Detail

ChunkAdjuster

public ChunkAdjuster()

Method Detail

initialize

public void initialize(UimaContext aContext)
                throws ResourceInitializationException

Performs initialization logic. This implementation just reads values for the configuration parameters. This method is not invoked for every document processed.

Throws:

ResourceInitializationException

See Also:

org.apache.uima.analysis_engine.annotator.BaseAnnotator#initialize(AnnotatorContext)

configInit

private void configInit()
                 throws ResourceInitializationException

Sets configuration parameters with values from the descriptor.

Throws:

ResourceInitializationException

process

public void process(JCas jcas)
             throws AnalysisEngineProcessException

Invokes this annotator's analysis logic. Invoked for each document processed. For each Sentence, look for the pattern, and adjust a chunk if the pattern is found.

Throws:

AnalysisEngineProcessException

annotateSentence

protected void annotateSentence(JCas jcas,
                    Sentence sent)
                         throws AnalysisEngineProcessException

Throws:

AnalysisEngineProcessException

annotateRange

protected void annotateRange(JCas jcas,
                 int rangeBegin,
                 int rangeEnd)
                      throws AnalysisEngineProcessException

A utility method that annotates a given range.

Throws:

AnalysisEngineProcessException

removeEnvelopedChunks

private void removeEnvelopedChunks(java.util.List<Chunk> list,
                         int i)

Remove from our local list of chunks the chunks that have been enveloped. This allows the rule to be applied again.

compareToPattern

private boolean compareToPattern(java.util.List<Chunk> list,
                       int i)

Compares the chunks at index i to the 1st element on the pattern, i+1 to the 2nd element, etc and returns true if the chunks starting at i fit the pattern

Parameters:

list - the list of chunks

i - the position within the list to compare to the pattern

Returns:

true if the pattern is matched by the chunks starting with element i in the list. Note if there aren't enough chunks in the list starting at i to match the pattern, returns false.

Throws:

AnnotatorProcessException

extendChunk

private static Chunk extendChunk(Chunk chunk,
                int newEnd)
                          throws AnalysisEngineProcessException

Update the end value for the chunk to have the new value

Parameters:

chunk - The chunk to update

newEnd - The new end value for the chunk.

Returns:

The updated Chunk

Throws:

AnnotatorProcessException

AnalysisEngineProcessException

createAnnotatorDescription

public static AnalysisEngineDescription createAnnotatorDescription(java.lang.String[] chunkPattern,
                                                   int patternIndex)
                                                            throws ResourceInitializationException

Throws:

ResourceInitializationException