I want to POStag an English sentence and do some processing. I would like to use openNLP. I have it installed
When I execute the command
I:\Workshop\Programming\nlp\opennlp-tools-1.5.0-bin\opennlp-tools-1.5.0>java -jar opennlp-tools-1.5.0.jar POSTagger models\en-pos-maxent.bin < Text.txt
It gives output POSTagging the input in Text.txt
Loading POS Tagger model ... done (4.009s)
My_PRP$ name_NN is_VBZ Shabab_NNP i_FW am_VBP 22_CD years_NNS old._.
Average: 66.7 sent/s
Total: 1 sent
Runtime: 0.015s
I hope it installed properly?
Now how do i do this POStagging from inside a java application? I have added the openNLPtools, jwnl, maxent jar to the project but how do i invoke the POStagging?
Here's some (old) sample code I threw together, with modernized code to follow:
package opennlp;
import opennlp.tools.cmdline.PerformanceMonitor;
import opennlp.tools.cmdline.postag.POSModelLoader;
import opennlp.tools.postag.POSModel;
import opennlp.tools.postag.POSSample;
import opennlp.tools.postag.POSTaggerME;
import opennlp.tools.tokenize.WhitespaceTokenizer;
import opennlp.tools.util.ObjectStream;
import opennlp.tools.util.PlainTextByLineStream;
import java.io.File;
import java.io.IOException;
import java.io.StringReader;
public class OpenNlpTest {
public static void main(String[] args) throws IOException {
POSModel model = new POSModelLoader().load(new File("en-pos-maxent.bin"));
PerformanceMonitor perfMon = new PerformanceMonitor(System.err, "sent");
POSTaggerME tagger = new POSTaggerME(model);
String input = "Can anyone help me dig through OpenNLP's horrible documentation?";
ObjectStream<String> lineStream =
new PlainTextByLineStream(new StringReader(input));
perfMon.start();
String line;
while ((line = lineStream.read()) != null) {
String whitespaceTokenizerLine[] = WhitespaceTokenizer.INSTANCE.tokenize(line);
String[] tags = tagger.tag(whitespaceTokenizerLine);
POSSample sample = new POSSample(whitespaceTokenizerLine, tags);
System.out.println(sample.toString());
perfMon.incrementCounter();
}
perfMon.stopAndPrintFinalResult();
}
}
The output is:
Loading POS Tagger model ... done (2.045s)
Can_MD anyone_NN help_VB me_PRP dig_VB through_IN OpenNLP's_NNP horrible_JJ documentation?_NN
Average: 76.9 sent/s
Total: 1 sent
Runtime: 0.013s
This is basically working from the POSTaggerTool class included as part of OpenNLP. The sample.getTags()
is a String
array that has the tag types themselves.
This requires direct file access to the training data, which is really, really lame.
An updated codebase for this is a little different (and probably more useful.)
First, a Maven POM:
<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>org.javachannel</groupId>
<artifactId>opennlp-example</artifactId>
<version>1.0-SNAPSHOT</version>
<dependencies>
<dependency>
<groupId>org.apache.opennlp</groupId>
<artifactId>opennlp-tools</artifactId>
<version>1.6.0</version>
</dependency>
<dependency>
<groupId>org.testng</groupId>
<artifactId>testng</artifactId>
<version>[6.8.21,)</version>
<scope>test</scope>
</dependency>
</dependencies>
<build>
<plugins>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-compiler-plugin</artifactId>
<version>3.1</version>
<configuration>
<source>1.8</source>
<target>1.8</target>
</configuration>
</plugin>
</plugins>
</build>
</project>
And here's the code, written as a test, therefore located in ./src/test/java/org/javachannel/opennlp/example
:
package org.javachannel.opennlp.example;
import opennlp.tools.cmdline.PerformanceMonitor;
import opennlp.tools.postag.POSModel;
import opennlp.tools.postag.POSSample;
import opennlp.tools.postag.POSTaggerME;
import opennlp.tools.tokenize.WhitespaceTokenizer;
import org.testng.annotations.DataProvider;
import org.testng.annotations.Test;
import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.net.URL;
import java.nio.channels.Channels;
import java.nio.channels.ReadableByteChannel;
import java.util.stream.Stream;
public class POSTest {
private void download(String url, File destination) throws IOException {
URL website = new URL(url);
ReadableByteChannel rbc = Channels.newChannel(website.openStream());
FileOutputStream fos = new FileOutputStream(destination);
fos.getChannel().transferFrom(rbc, 0, Long.MAX_VALUE);
}
@DataProvider
Object[][] getCorpusData() {
return new Object[][][]{{{
"Can anyone help me dig through OpenNLP's horrible documentation?"
}}};
}
@Test(dataProvider = "getCorpusData")
public void showPOS(Object[] input) throws IOException {
File modelFile = new File("en-pos-maxent.bin");
if (!modelFile.exists()) {
System.out.println("Downloading model.");
download("http://opennlp.sourceforge.net/models-1.5/en-pos-maxent.bin", modelFile);
}
POSModel model = new POSModel(modelFile);
PerformanceMonitor perfMon = new PerformanceMonitor(System.err, "sent");
POSTaggerME tagger = new POSTaggerME(model);
perfMon.start();
Stream.of(input).map(line -> {
String whitespaceTokenizerLine[] = WhitespaceTokenizer.INSTANCE.tokenize(line.toString());
String[] tags = tagger.tag(whitespaceTokenizerLine);
POSSample sample = new POSSample(whitespaceTokenizerLine, tags);
perfMon.incrementCounter();
return sample.toString();
}).forEach(System.out::println);
perfMon.stopAndPrintFinalResult();
}
}
This code doesn't actually test anything - it's a smoke test, if anything - but it should serve as a starting point. Another (potentially) nice thing is that it downloads a model for you if you don't have it downloaded already.