/**
* opennlp part of speech tagging
*
* @param tokens
* @return
* @return
* @throws IOException
*/
public static List<String> taggerAndStemmer(String inputFile) throws IOException {
String tags[] = null;
String[] tokens = tokenizer(inputFile);
List<String> token_tag = new ArrayList<String>();
List<String> stemmedwords = new ArrayList<String>();
PlingStemmer stemmer = new PlingStemmer();
try (InputStream posModelStream = new FileInputStream("openNLPmodels\\en-pos-maxent.bin");
InputStream chunkerStream = new FileInputStream("openNLPmodels\\en-chunker.bin"); ) {
POSModel modelTagger = new POSModel(posModelStream);
POSTaggerME tagger = new POSTaggerME(modelTagger);
tags = tagger.tag(tokens);
for (int i = 0; i < tags.length; i++) {
String w = tokens[i].toLowerCase(); // lowercase phrase
w = stemmer.stem(w); // stemming phrase
if (tags[i].equals("NNS")) token_tag.add(w + "/" + "NN");
else token_tag.add(w + "/" + tags[i]);
}
} catch (IOException ex) {
// Handle exceptions
}
return token_tag;
}
/**
* stemmer (remove stop words) remove special characters, duplicate spaces, numbers, stop words
* return a list of words
*
* @param rawdatapath
* @return
* @throws IOException
*/
public static List<String> cleanAndstemmer(String rawdatapath) throws IOException {
String line = "";
String combline = "";
// read input data
try {
BufferedReader br = new BufferedReader(new FileReader(rawdatapath));
while ((line = br.readLine()) != null) combline = combline + " " + line;
} catch (FileNotFoundException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
/** */
// remove url
// combline = combline.replaceAll("https?://\\S+\\s?", "");
// replace "- " with a white space
// combline = combline.replaceAll("-", " ");
// remove non letter
// combline = combline.replaceAll("[^a-zA-Z\\s]", "");
// one other way: combline=combline.replaceAll("[-+^,\\.\\;:?()'><*&*#%{}=$\\d]", "");
// remove duplicate spaces
combline = combline.replaceAll("\\s+", " ").trim();
List<String> words = Lists.newArrayList(combline.split(" "));
// stemming
List<String> stemmedwords = new ArrayList<String>();
PlingStemmer stemmer = new PlingStemmer();
for (String w : words) {
w = w.toLowerCase();
if (!w.equals("'s")) w = stemmer.stem(w);
stemmedwords.add(w);
}
return stemmedwords;
}
