java - Apache OpenNLP : java. io.FileInputStream 无法转换为 opennlp.tools.util.InputStreamFactory

Question

我正在尝试使用 Apache OpenNLP 1.7 构建自定义 NER。来自可用文档 Here ，我开发了如下代码

import java.io.BufferedOutputStream;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.nio.charset.Charset;

import opennlp.tools.namefind.NameFinderME;
import opennlp.tools.namefind.NameSample;
import opennlp.tools.namefind.NameSampleDataStream;
import opennlp.tools.namefind.TokenNameFinderFactory;
import opennlp.tools.namefind.TokenNameFinderModel;
import opennlp.tools.util.ObjectStream;
import opennlp.tools.util.PlainTextByLineStream;
import opennlp.tools.util.TrainingParameters;

public class PersonClassifierTrainer {

        static String modelFile = "/opt/NLP/data/en-ner-customperson.bin";

        public static void main(String[] args) throws IOException {

            Charset charset = Charset.forName("UTF-8");
            **ObjectStream<String> lineStream = new PlainTextByLineStream(new FileInputStream("/opt/NLP/data/person.train"), charset);**
            ObjectStream<NameSample> sampleStream = new NameSampleDataStream(lineStream);

            TokenNameFinderModel model;
            TokenNameFinderFactory nameFinderFactory = null;

            try {
                model = NameFinderME.train("en", "person", sampleStream, TrainingParameters.defaultParams(),
                        nameFinderFactory);
            } finally {
                sampleStream.close();
            }

            BufferedOutputStream modelOut = null;

            try {
                modelOut = new BufferedOutputStream(new FileOutputStream(modelFile));
                model.serialize(modelOut);
            } finally {
                if (modelOut != null)
                    modelOut.close();
            }
        }
    }

上面突出显示的代码显示 - 'Cast argument 'file' to 'insputstreamfactory'

我不得不强制转换它，否则它会显示错误。

现在，当我运行我的代码时，出现以下错误

java.io.FileInputStream cannot be cast to opennlp.tools.util.InputStreamFactory

这里有什么遗漏吗？

编辑 1:Person.train 文件有这个数据

<START:person> Hardik <END> is a software Professional.<START:person> Hardik works at company<END> and <START:person> is part of development team<END>. <START:person> Hardik<END> lives in New York
<START:person> Hardik<END> loves R statistical software
<START:person> Hardik<END> is a student at ISB
<START:person> Hardik<END> loves nature

Edit2:我现在遇到空指针异常，有什么帮助吗？

Answer 1

您需要一个 InputStreamFactory 实例，它将检索您的 InputStream。此外，TokenNameFinderFactory 不能为 null。

public class PersonClassifierTrainer {

    static String modelFile = "/opt/NLP/data/en-ner-customperson.bin";

    public static void main(String[] args) throws IOException {

        InputStreamFactory isf = new InputStreamFactory() {
            public InputStream createInputStream() throws IOException {
                return new FileInputStream("/opt/NLP/data/person.train");
            }
        };

        Charset charset = Charset.forName("UTF-8");
        ObjectStream<String> lineStream = new PlainTextByLineStream(isf, charset);
        ObjectStream<NameSample> sampleStream = new NameSampleDataStream(lineStream);

        TokenNameFinderModel model;
        TokenNameFinderFactory nameFinderFactory = new TokenNameFinderFactory();

        try {
            model = NameFinderME.train("en", "person", sampleStream, TrainingParameters.defaultParams(),
                    nameFinderFactory);
        } finally {
            sampleStream.close();
        }

        BufferedOutputStream modelOut = null;

        try {
            modelOut = new BufferedOutputStream(new FileOutputStream(modelFile));
            model.serialize(modelOut);
        } finally {
            if (modelOut != null)
                modelOut.close();
        }
    }
}

编辑 1:Person.train 文件有这个数据

<START:person> Hardik <END> is a software Professional.<START:person> Hardik works at company<END> and <START:person> is part of development team<END>. <START:person> Hardik<END> lives in New York
<START:person> Hardik<END> loves R statistical software
<START:person> Hardik<END> is a student at ISB
<START:person> Hardik<END> loves nature