Multi-term named entities in Stanford Named Entity Recognizer

Question

I\'m using the Stanford Named Entity Recognizer http://nlp.stanford.edu/software/CRF-NER.shtml and it\'s working fine. This is

    List&         


        

Answer 1

The counterpart of the classifyToCharacterOffsets method is that (AFAIK) you can't access the label of the entities.

As proposed by Christopher, here is an example of a loop which assembles "adjacent non-O things". This example also counts the number of occurrences.

public HashMap> extractEntities(String text){

    HashMap> entities =
            new HashMap>();

    for (List lcl : classifier.classify(text)) {

        Iterator iterator = lcl.iterator();

        if (!iterator.hasNext())
            continue;

        CoreLabel cl = iterator.next();

        while (iterator.hasNext()) {
            String answer =
                    cl.getString(CoreAnnotations.AnswerAnnotation.class);

            if (answer.equals("O")) {
                cl = iterator.next();
                continue;
            }

            if (!entities.containsKey(answer))
                entities.put(answer, new HashMap());

            String value = cl.getString(CoreAnnotations.ValueAnnotation.class);

            while (iterator.hasNext()) {
                cl = iterator.next();
                if (answer.equals(
                        cl.getString(CoreAnnotations.AnswerAnnotation.class)))
                    value = value + " " +
                           cl.getString(CoreAnnotations.ValueAnnotation.class);
                else {
                    if (!entities.get(answer).containsKey(value))
                        entities.get(answer).put(value, 0);

                    entities.get(answer).put(value,
                            entities.get(answer).get(value) + 1);

                    break;
                }
            }

            if (!iterator.hasNext())
                break;
        }
    }

    return entities;
}