我怎样才能获得树的斯坦福德依赖关系“nsubj”的主体价值？

Question

这是我的代码的一部分：

String sentence="My dog also likes eating sausage."; 
LexicalizedParser lp = new LexicalizedParser("englishPCFG.ser.gz"); 
TokenizerFactory tf = PTBTokenizer.factory(false, new WordTokenFactory()); 
TreePrint tp = new TreePrint("penn,typedDependenciesCollapsed"); 

List tokens = tf.getTokenizer(new StringReader(sentence)).tokenize(); 
lp.parse(tokens); // parse the tokens 
Tree t = lp.getBestParse(); 

我怎样才能获得主题（狗）的价值？

这是一种依赖，我想提取主题：

nsubj(likes-4, dog-2) 

Answer 1

尝试是这样的：

String sentence="My dog also likes eating sausage."; 
LexicalizedParser lp = new LexicalizedParser("resources/stanford-parser-2011-06-27/grammar/englishPCFG.ser.gz"); 
TokenizerFactory tf = PTBTokenizer.factory(false, new WordTokenFactory()); 
TreePrint tp = new TreePrint("penn,typedDependenciesCollapsed"); 

List tokens = tf.getTokenizer(new StringReader(sentence)).tokenize(); 
lp.parse(tokens); // parse the tokens 
Tree t = lp.getBestParse(); 

TreebankLanguagePack languagePack = new PennTreebankLanguagePack(); 
GrammaticalStructure structure = languagePack.grammaticalStructureFactory().newGrammaticalStructure(t); 
Collection<TypedDependency> typedDependencies = structure.typedDependenciesCollapsed(); 

for(TypedDependency td : typedDependencies) { 
    if(td.reln().equals(EnglishGrammaticalRelations.NOMINAL_SUBJECT)) { 
    System.out.println(td); 
    } 
} 

，它将打印：

nsubj(likes-4, dog-2)