package edu.stanford.nlp.trees;
import java.util.List;
import edu.stanford.nlp.ling.HasLemma;
import edu.stanford.nlp.ling.HasTag;
import edu.stanford.nlp.ling.Label;
import edu.stanford.nlp.ling.TaggedWord;
import edu.stanford.nlp.process.Morphology;
public class TreeLemmatizer implements TreeTransformer {
public Tree transformTree(Tree t) {
Morphology morphology = new Morphology();
List<TaggedWord> tagged = null;
int index = 0;
for (Tree leaf : t.getLeaves()) {
Label label = leaf.label();
if (label == null) {
continue;
}
String tag;
if (!(label instanceof HasTag) || ((HasTag) label).tag() == null) {
if (tagged == null) {
tagged = t.taggedYield();
}
tag = tagged.get(index).tag();
} else {
tag = ((HasTag) label).tag();
}
if (!(label instanceof HasLemma)) {
throw new IllegalArgumentException("Got a tree with labels which do not support lemma");
}
((HasLemma) label).setLemma(morphology.lemma(label.value(), tag, true));
++index;
}
return t;
}
}