On Wed, Jan 7, 2009 at 11:55 AM, Roberto Franchini
<[email protected]> wrote:
> Hi,
> I need to get a parent annotation of a given one.
> Example: given a Token annotation, I want to know the parent Sentence.
> I need to extract it from a cas. Maybe filters or constraint?
> I mean a sort of "parentIterator", as the subiterator, but "reversed" :)
> Regards,
> Roberto
Here's the answer with filtered iterator:
public static FSIterator getAnnotationParent(JCas jcas, Annotation
son, Type parent) {
ConstraintFactory cf = jcas.getConstraintFactory();
FSIntConstraint beginCons = cf.createIntConstraint();
beginCons.leq(son.getBegin());
FSIntConstraint endCons = cf.createIntConstraint();
endCons.geq(son.getEnd());
FSTypeConstraint typeCons = cf.createTypeConstraint();
Type type = jcas.getTypeSystem().getType(parent.getName());
typeCons.add(type);
Feature beginFeature = type.getFeatureByBaseName("begin");
FeaturePath beginPath = jcas.createFeaturePath();
beginPath.addFeature(beginFeature);
Feature endFeature = type.getFeatureByBaseName("end");
FeaturePath endPath = jcas.createFeaturePath();
endPath.addFeature(endFeature);
FSMatchConstraint begin = cf.embedConstraint(beginPath,
beginCons);
FSMatchConstraint end = cf.embedConstraint(endPath, endCons);
FSMatchConstraint beginAndEnd = cf.and(begin, end);
FSMatchConstraint beginAndEndAndType = cf.and(beginAndEnd,
typeCons);
FSIterator filteredIterator =
jcas.createFilteredIterator(jcas.getAnnotationIndex(parent).iterator(),
beginAndEndAndType);
return filteredIterator;
}
Here's a test (junit).
@Test
public void getParent() throws Exception {
AnalysisEngine tokenizer = AnnotatorFactory.createTokenizer();
//this is my own factory for tests!!!
JCas jcas = tokenizer.newJCas();
jcas.setDocumentText("My name is .");
Sentence sentence = new Sentence(jcas, 0,
jcas.getDocumentText().length());
sentence.addToIndexes();
tokenizer.process(jcas);
FSIterator iterator =
jcas.getAnnotationIndex(Token.type).iterator();
iterator.moveToNext();
Token token = (Token) iterator.get();
FSIterator parentIt = CasUtil.getAnnotationParent(jcas, token,
sentence.getType());
assertNotNull(parentIt);
parentIt.moveToFirst();
Sentence sentence2 = (Sentence) parentIt.get();
assertNotNull(sentence2);
assertEquals(sentence.getCoveredText(),
sentence2.getCoveredText());
}
It works :)
Roberto
--
Roberto Franchini
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