public Parse getHead()

in opennlp-coref/src/main/java/opennlp/tools/coref/mention/PTBHeadFinder.java [55:107]
47 lines of code
18 McCabe index (conditional complexity)

  public Parse getHead(Parse p) {
    if (p == null) {
      return null;
    }
    if (p.isNounPhrase()) {
      List<Parse> parts = p.getSyntacticChildren();
      //shallow parse POS
      if (parts.size() > 2) {
        Parse child0 = parts.get(0);
        Parse child1 = parts.get(1);
        Parse child2 = parts.get(2);
        if (child1.isToken() && child1.getSyntacticType().equals("POS")
            && child0.isNounPhrase() && child2.isNounPhrase()) {
          return child2;
        }
      }
      //full parse POS
      if (parts.size() > 1) {
        Parse child0 = parts.get(0);
        if (child0.isNounPhrase()) {
          List<Parse> ctoks = child0.getTokens();
          if (ctoks.size() == 0) {
            System.err.println("PTBHeadFinder: NP " + child0 + " with no tokens");
          }
          Parse tok = ctoks.get(ctoks.size() - 1);
          if (tok.getSyntacticType().equals("POS")) {
            return null;
          }
        }
      }
      //coordinated nps are their own entities
      if (parts.size() > 1) {
        for (int pi = 1; pi < parts.size() - 1; pi++) {
          Parse child = parts.get(pi);
          if (child.isToken() && child.getSyntacticType().equals("CC")) {
            return null;
          }
        }
      }
      //all other NPs
      for (Parse child : parts) {
        //System.err.println("PTBHeadFinder.getHead: "+p.getSyntacticType()+" "+p
        // +" child "+pi+"="+child.getSyntacticType()+" "+child);
        if (child.isNounPhrase()) {
          return child;
        }
      }
      return null;
    }
    else {
      return null;
    }
  }