java - 斯坦福 NLP 在运行代码时给出异常

Question

我正在尝试使用文件输入运行此代码并将其输出到另一个文件:

import java.util.*;

import edu.stanford.nlp.pipeline.*;
import edu.stanford.nlp.io.*;
import edu.stanford.nlp.ling.*;
import edu.stanford.nlp.neural.rnn.*;
import edu.stanford.nlp.sentiment.*;
import edu.stanford.nlp.sentiment.SentimentCoreAnnotations.SentimentAnnotatedTree;
import edu.stanford.nlp.trees.*;
import edu.stanford.nlp.util.*;

import java.io.BufferedReader;
//import java.io.BufferedWriter;
import java.io.FileReader;
//import java.io.FileWriter;
import java.io.IOException;
import java.io.PrintWriter;
public class TestCoreNLP {

  public static void main(String[] args) throws IOException {
    PrintWriter out =  new PrintWriter("/home/aims/Desktop/outputNLP1");

    Properties props=new Properties();
    props.setProperty("annotators","tokenize, ssplit, pos,lemma");
    StanfordCoreNLP pipeline = new StanfordCoreNLP(props);
    Annotation annotation;  
    String readString = "";
        //PrintWriter pw = null;
    BufferedReader br  = new BufferedReader ( new FileReader ( "/home/aims/Desktop/testNLP" )  ) ;
        //pw = new PrintWriter ( new BufferedWriter ( new FileWriter ( "/home/aims/Desktop/outputNLP", true )  )  ) ;      
    //String x = "";
        while  (( readString = br.readLine ())  != null)   {
            // pw.println ( readString ) ; 
             //String xx=readString;x=xx;//System.out.println("OKKKKK"); 
        annotation = new Annotation(readString);
 //System.out.print(readString);
    pipeline.annotate(annotation);    //System.out.println("LamoohAKA");
    pipeline.prettyPrint(annotation, out);
    out.println();
    out.println("The top level annotation");
    out.println(annotation.toShorterString());
    List<CoreMap> sentences = annotation.get(CoreAnnotations.SentencesAnnotation.class);

    if (sentences != null && !sentences.isEmpty()) {
        for (int i = 0; i < sentences.size (); i++) {
            CoreMap sentence = sentences.get(i);
            Tree tree = sentence.get(SentimentAnnotatedTree.class);//Tree tree = sentence.get(SentimentAnnotatedTree.class);
            int sentiment = RNNCoreAnnotations.getPredictedClass(tree);
            String sentimentName = sentence.get(SentimentCoreAnnotations.SentimentClass.class);

            out.println();
            out.println("The sentence is:");
            out.println(sentence.toShorterString());
            out.println();
            out.println("Sentiment of \n> \""+sentence.get(CoreAnnotations.TextAnnotation.class)+"\"\nis: " + sentiment+" (i.e., "+sentimentName+")");
            out.println();
          }
    }

    IOUtils.closeIgnoringExceptions(out);
        }
        br.close (  ) ;
   // pw.close (  ) ;
    System.out.println("Done...");


  }

}

这段代码的输入是:

I am glad you are here.
I will see you tomorrow.
I hate you.
Remember me!
I like ice-cream to utmost level of likeness.

当我使用 Eclipse Neon 运行代码时，出现以下错误:

[main] INFO edu.stanford.nlp.pipeline.StanfordCoreNLP - Adding annotator tokenize
[main] INFO edu.stanford.nlp.pipeline.TokenizerAnnotator - No tokenizer type provided. Defaulting to PTBTokenizer.
[main] INFO edu.stanford.nlp.pipeline.StanfordCoreNLP - Adding annotator ssplit
[main] INFO edu.stanford.nlp.pipeline.StanfordCoreNLP - Adding annotator pos
[main] INFO edu.stanford.nlp.tagger.maxent.MaxentTagger - Loading POS tagger from edu/stanford/nlp/models/pos-tagger/english-left3words/english-left3words-distsim.tagger ... done [2.4 sec].
[main] INFO edu.stanford.nlp.pipeline.StanfordCoreNLP - Adding annotator lemma
Exception in thread "main" java.lang.NullPointerException
    at edu.stanford.nlp.neural.rnn.RNNCoreAnnotations.getPredictedClass(RNNCoreAnnotations.java:83)
    at TestCoreNLP.main(TestCoreNLP.java:48)

现在我不明白为什么会发生这种情况？我应该怎么做才能成功运行此代码？

Answer 1

您没有在管道中运行情感注释器或解析器。这是一个命令行调用，显示运行管道并获取情绪。通过设置管道的属性以匹配此调用指定的属性，您可以轻松地使其适应 Java 代码。

java -Xmx8g edu.stanford.nlp.pipeline.StanfordCoreNLP -annotators tokenize,ssplit,pos,lemma,parse,sentiment -parse.binaryTrees -file example-sentence.txt -outputFormat text

您需要将 parse 和 sentiment 注释器添加到管道中，并且需要确保 parse 注释器生成二叉树parse.binaryTrees 属性设置为 true。

以下是一些示例代码，显示了访问情绪:

import edu.stanford.nlp.ling.*;
import edu.stanford.nlp.pipeline.*;
import edu.stanford.nlp.sentiment.*;
import edu.stanford.nlp.util.*;
import java.util.Properties;

public class SentimentExample {

  public static void main(String[] args) {
    Annotation document = new Annotation("I liked the first movie.  I hated the second movie.");
    Properties props = new Properties();
    props.setProperty("annotators", "tokenize,ssplit,pos,lemma,ner,parse,sentiment");
    props.setProperty("parse.binaryTrees","true");
    StanfordCoreNLP pipeline = new StanfordCoreNLP(props);
    pipeline.annotate(document);
    for (CoreMap sentence : document.get(CoreAnnotations.SentencesAnnotation.class)) {
      System.out.println("---");
      System.out.println(sentence.get(CoreAnnotations.TextAnnotation.class));
      System.out.println(sentence.get(SentimentCoreAnnotations.SentimentClass.class));
    }
  }
}