package cn.edu.bjut.chapter2;

import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.InputStream;

import opennlp.tools.postag.POSModel;
import opennlp.tools.postag.POSTaggerME;

public class PoSTaggerByOpenNLP {
	private static POSTaggerME tagger = null;
	private static final String MODEL_FILE = 
			"resource/opennlp-en-ud-ewt-pos-1.0-1.9.3.bin";

	private static void loadModel(String fname) {
		POSModel model = null;
		try {
			InputStream stream = new FileInputStream(fname);

			try {
				model = new POSModel(stream);
			} catch (IOException e) {
				e.printStackTrace();
			} finally {
				if (stream != null) {
					try {
						stream.close();
					} catch (IOException e) {
						e.printStackTrace();
					}
				}
			}

			tagger = new POSTaggerME(model);
		} catch (FileNotFoundException e) {
			e.printStackTrace();
		}
	}

	public static String[] tag(String[] tokens) {
		if (tagger == null) {
			loadModel(MODEL_FILE);
		}

		return tagger.tag(tokens);
	}

	public static void main(String[] args) {
		String tokens[] = new String[] { "Most", "large", "cities", "in", "the", 
				"US", "had", "morning", "and", "afternoon", "newspapers", "." };
		String tags[] = tag(tokens);

		for (int i = 0; i < tags.length; i++) {
			System.out.println(tokens[i] + "\t" + tags[i]);
		}
	}
}