package edu.stanford.nlp.parser.lexparser;
import edu.stanford.nlp.ling.CategoryWordTag;
import edu.stanford.nlp.ling.Label;
import edu.stanford.nlp.trees.Tree;
import edu.stanford.nlp.trees.TreeTransformer;
import java.util.*;
/**
*/
public class CNFTransformers {
private CNFTransformers() {}
static class ToCNFTransformer implements TreeTransformer {
public Tree transformTree(Tree t) {
if (t.isLeaf()) {
return t.treeFactory().newLeaf(t.label());
}
Tree[] children = t.children();
if (children.length > 1 || t.isPreTerminal() || t.label().value().startsWith("ROOT")) {
Label label = t.label();
Tree[] transformedChildren = new Tree[children.length];
for (int childIndex = 0; childIndex < children.length; childIndex++) {
Tree child = children[childIndex];
transformedChildren[childIndex] = transformTree(child);
}
return t.treeFactory().newTreeNode(label, Arrays.asList(transformedChildren));
}
Tree tree = t;
List<String> conjoinedList = new ArrayList<String>();
while (tree.children().length == 1 && !tree.isPrePreTerminal()) {
String nodeString = tree.label().value();
if (!nodeString.startsWith("@")) {
conjoinedList.add(nodeString);
}
tree = tree.children()[0];
}
String nodeString = tree.label().value();
if (!nodeString.startsWith("@")) {
conjoinedList.add(nodeString);
}
String conjoinedLabels;
if (conjoinedList.size() > 1) {
StringBuilder conjoinedLabelsBuilder = new StringBuilder();
for (String s : conjoinedList) {
conjoinedLabelsBuilder.append("&");
conjoinedLabelsBuilder.append(s);
}
conjoinedLabels = conjoinedLabelsBuilder.toString();
} else if (conjoinedList.size() == 1) {
conjoinedLabels = conjoinedList.iterator().next();
} else {
return transformTree(t.children()[0]);
}
children = tree.children();
Label label = t.label().labelFactory().newLabel(conjoinedLabels);
Tree[] transformedChildren = new Tree[children.length];
for (int childIndex = 0; childIndex < children.length; childIndex++) {
Tree child = children[childIndex];
transformedChildren[childIndex] = transformTree(child);
}
return t.treeFactory().newTreeNode(label, Arrays.asList(transformedChildren));
}
}
static class FromCNFTransformer implements TreeTransformer {
public Tree transformTree(Tree t) {
if (t.isLeaf()) {
return t.treeFactory().newLeaf(t.label());
}
Tree[] children = t.children();
Tree[] transformedChildren = new Tree[children.length];
for (int childIndex = 0; childIndex < children.length; childIndex++) {
Tree child = children[childIndex];
transformedChildren[childIndex] = transformTree(child);
}
Label label = t.label();
if (!label.value().startsWith("&")) {
return t.treeFactory().newTreeNode(label, Arrays.asList(transformedChildren));
}
String[] nodeStrings = label.value().split("&");
int i = nodeStrings.length - 1;
label = t.label().labelFactory().newLabel(nodeStrings[i]);
Tree result = t.treeFactory().newTreeNode(label, Arrays.asList(transformedChildren));
while (i > 1) {
i--;
label = t.label().labelFactory().newLabel(nodeStrings[i]);
result = t.treeFactory().newTreeNode(label, Collections.singletonList(result));
}
return result;
}
}
public static void main(String[] args) {
CategoryWordTag.printWordTag = false;
String path = args[0];
List<Tree> trees = TreebankAnnotator.getTrees(path, 200, 219, 0, 10);
List<Tree> annotatedTrees = new TreebankAnnotator(new Options(), path).annotateTrees(trees);
for (Tree tree : annotatedTrees) {
System.out.println("ORIGINAL:\n");
tree.pennPrint();
System.out.println("CNFed:\n");
Tree cnfTree = new ToCNFTransformer().transformTree(tree);
cnfTree.pennPrint();
System.out.println("UnCNFed:\n");
Tree unCNFTree = new FromCNFTransformer().transformTree(cnfTree);
unCNFTree.pennPrint();
System.out.println("\n\n");
}
}
}