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Stanford CoreNLP provides a set of natural language analysis tools which can take raw English language text input and give the base forms of words, their parts of speech, whether they are names of companies, people, etc., normalize dates, times, and numeric quantities, mark up the structure of sentences in terms of phrases and word dependencies, and indicate which noun phrases refer to the same entities. It provides the foundational building blocks for higher level text understanding applications.

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package edu.stanford.nlp.tagger.io;

import java.io.BufferedReader;
import java.io.FileInputStream;
import java.io.InputStreamReader;
import java.io.IOException;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;
import java.util.NoSuchElementException;
import edu.stanford.nlp.ling.TaggedWord;

public class TSVTaggedFileReader implements TaggedFileReader {
  final BufferedReader reader;
  final String filename;
  final int wordColumn, tagColumn;
  List next = null;
  int linesRead = 0;

  static final int DEFAULT_WORD_COLUMN = 0;
  static final int DEFAULT_TAG_COLUMN = 1;

  public TSVTaggedFileReader(TaggedFileRecord record) {
    filename = record.file;
    try {
      reader = new BufferedReader(new InputStreamReader
                                  (new FileInputStream(filename),
                                   record.encoding));
    } catch (IOException e) {
      throw new RuntimeException(e);
    }
    wordColumn = ((record.wordColumn == null) ?
                  DEFAULT_WORD_COLUMN : record.wordColumn);
    tagColumn = ((record.tagColumn == null) ?
                 DEFAULT_TAG_COLUMN : record.tagColumn);
    primeNext();
  }

  public Iterator> iterator() { return this; }

  public String filename() { return filename; }

  public boolean hasNext() { return next != null; }

  public List next() {
    if (next == null) {
      throw new NoSuchElementException();
    }
    List thisIteration = next;
    primeNext();
    return thisIteration;
  }


  void primeNext() {
    // eat all blank lines until we hit the next block of text
    String line = "";
    while (line.trim().equals("")) {
      try {
        line = reader.readLine();
        ++linesRead;
      } catch (IOException e) {
        throw new RuntimeException(e);
      }
      if (line == null) {
        next = null;
        return;
      }
    }
    // we hit something with text, so now we read one line at a time
    // until we hit the next blank line.  the next blank line (or EOF)
    // ends the sentence.
    next = new ArrayList<>();
    while (line != null && !line.trim().equals("")) {
      String[] pieces = line.split("\t");
      if (pieces.length <= wordColumn || pieces.length <= tagColumn) {
        throw new IllegalArgumentException("File " + filename + " line #" +
                                           linesRead + " too short");
      }
      String word = pieces[wordColumn];
      String tag = pieces[tagColumn];
      next.add(new TaggedWord(word, tag));
      try {
        line = reader.readLine();
        ++linesRead;
      } catch (IOException e) {
        throw new RuntimeException(e);
      }
    }
  }

  public void remove() { throw new UnsupportedOperationException(); }
}