Maven Apache OpenNLP 工具获取 NullPointerException

Question

我正在尝试将 Apache OpenNLP 与 Maven 一起使用。我在 pom

中添加依赖项

<groupId>org.example</groupId>
<artifactId>nlp-fun</artifactId>
<version>1.0-SNAPSHOT</version>

<properties>
    <maven.compiler.target>1.8</maven.compiler.target>
    <maven.compiler.source>1.8</maven.compiler.source>
</properties>

<dependencies>
    <!-- https://mvnrepository.com/artifact/org.apache.opennlp/opennlp-tools -->
    <dependency>
        <groupId>org.apache.opennlp</groupId>
        <artifactId>opennlp-tools</artifactId>
        <version>1.9.2</version>
    </dependency>

</dependencies>

当我运行下面的代码创建了一个LanguageDetectorModel对象

public class Program {

public void fun() throws Exception{
    InputStream targetStream = new FileInputStream(new File("C:\Users\aaa\Desktop\nlp-fun\src\main\input.txt"));
    LanguageDetectorModel m = new LanguageDetectorModel(targetStream);
    LanguageDetector myCategorizer = new LanguageDetectorME(m);
}

public static void main(String[] args) throws Exception{
    Program program = new Program();
    program.fun();
}

}

我收到以下 NullPointerException，但我不确定该怎么做。我还尝试将 opennlp-tools 添加为外部 jar，但这也没有用

Exception in thread "main" java.lang.NullPointerException
at opennlp.tools.util.model.BaseModel.getManifestProperty(BaseModel.java:506)
at opennlp.tools.util.model.BaseModel.initializeFactory(BaseModel.java:248)
at opennlp.tools.util.model.BaseModel.loadModel(BaseModel.java:234)
at opennlp.tools.util.model.BaseModel.<init>(BaseModel.java:176)
at opennlp.tools.langdetect.LanguageDetectorModel.<init>(LanguageDetectorModel.java:50)
at Program.fun(Program.java:18)
at Program.main(Program.java:24)

Answer 1

targetStream 应该是语言检测模型。您可以从 OpenNLP website. Next, you can use the model to determine the language of the text. See the OpenNLP User's Manual for an example 下载模型文件 (langdetect-183.bin)，也复制如下：

InputStream is = new FileInputStream(new File("c:\path\to\langdetect-183.bin"));
LanguageDetectorModel m = new LanguageDetectorModel(is);

String inputText = "What language is this text?"
LanguageDetector myCategorizer = new LanguageDetectorME(m);

// Get the most probable language
Language bestLanguage = myCategorizer.predictLanguage(inputText);
System.out.println("Best language: " + bestLanguage.getLang());
System.out.println("Best language confidence: " + bestLanguage.getConfidence());

// Get an array with the most probable languages
Language[] languages = myCategorizer.predictLanguages(null);

Maven Apache OpenNLP 工具获取 NullPointerException

Maven Apache OpenNLP tools getting NullPointerException

java

maven

nullpointerexception

opennlp