package di.uniba.it.tri.tokenizer;
import java.util.regex.*;
import java.util.Arrays;
import java.util.List;
import java.util.ArrayList;
import org.apache.commons.lang3.StringEscapeUtils;
/**
* Twokenize -- a tokenizer designed for Twitter text in English and some other
* European languages. This is the Java version. If you want the old Python
* version, see: http://github.com/brendano/tweetmotif
*
* This tokenizer code has gone through a long history:
*
* (1) Brendan O'Connor wrote original version in Python,
* http://github.com/brendano/tweetmotif TweetMotif: Exploratory Search and
* Topic Summarization for Twitter. Brendan O'Connor, Michel Krieger, and David
* Ahn. ICWSM-2010 (demo track),
* http://brenocon.com/oconnor_krieger_ahn.icwsm2010.tweetmotif.pdf (2a) Kevin
* Gimpel and Daniel Mills modified it for POS tagging for the CMU ARK Twitter
* POS Tagger (2b) Jason Baldridge and David Snyder ported it to Scala (3)
* Brendan bugfixed the Scala port and merged with POS-specific changes for the
* CMU ARK Twitter POS Tagger (4) Tobi Owoputi ported it back to Java and added
* many improvements (2012-06)
*
* Current home is http://github.com/brendano/ark-tweet-nlp and
* http://www.ark.cs.cmu.edu/TweetNLP
*
* There have been at least 2 other Java ports, but they are not in the lineage
* for the code here.
*/
public class Twokenize {
static Pattern Contractions = Pattern.compile("(?i)(\\w+)(n['’′]t|['’′]ve|['’′]ll|['’′]d|['’′]re|['’′]s|['’′]m)$");
static Pattern Whitespace = Pattern.compile("[\\s\\p{Zs}]+");
static String punctChars = "['\"“”‘’.?!…,:;]";
//static String punctSeq = punctChars+"+"; //'anthem'. => ' anthem '.
static String punctSeq = "['\"“”‘’]+|[.?!,…]+|[:;]+"; //'anthem'. => ' anthem ' .
static String entity = "&(?:amp|lt|gt|quot);";
// URLs
// BTO 2012-06: everyone thinks the daringfireball regex should be better, but they're wrong.
// If you actually empirically test it the results are bad.
// Please see https://github.com/brendano/ark-tweet-nlp/pull/9
static String urlStart1 = "(?:https?://|\\bwww\\.)";
static String commonTLDs = "(?:com|org|edu|gov|net|mil|aero|asia|biz|cat|coop|info|int|jobs|mobi|museum|name|pro|tel|travel|xxx)";
static String ccTLDs = "(?:ac|ad|ae|af|ag|ai|al|am|an|ao|aq|ar|as|at|au|aw|ax|az|ba|bb|bd|be|bf|bg|bh|bi|bj|bm|bn|bo|br|bs|bt|"
+ "bv|bw|by|bz|ca|cc|cd|cf|cg|ch|ci|ck|cl|cm|cn|co|cr|cs|cu|cv|cx|cy|cz|dd|de|dj|dk|dm|do|dz|ec|ee|eg|eh|"
+ "er|es|et|eu|fi|fj|fk|fm|fo|fr|ga|gb|gd|ge|gf|gg|gh|gi|gl|gm|gn|gp|gq|gr|gs|gt|gu|gw|gy|hk|hm|hn|hr|ht|"
+ "hu|id|ie|il|im|in|io|iq|ir|is|it|je|jm|jo|jp|ke|kg|kh|ki|km|kn|kp|kr|kw|ky|kz|la|lb|lc|li|lk|lr|ls|lt|"
+ "lu|lv|ly|ma|mc|md|me|mg|mh|mk|ml|mm|mn|mo|mp|mq|mr|ms|mt|mu|mv|mw|mx|my|mz|na|nc|ne|nf|ng|ni|nl|no|np|"
+ "nr|nu|nz|om|pa|pe|pf|pg|ph|pk|pl|pm|pn|pr|ps|pt|pw|py|qa|re|ro|rs|ru|rw|sa|sb|sc|sd|se|sg|sh|si|sj|sk|"
+ "sl|sm|sn|so|sr|ss|st|su|sv|sy|sz|tc|td|tf|tg|th|tj|tk|tl|tm|tn|to|tp|tr|tt|tv|tw|tz|ua|ug|uk|us|uy|uz|"
+ "va|vc|ve|vg|vi|vn|vu|wf|ws|ye|yt|za|zm|zw)"; //TODO: remove obscure country domains?
static String urlStart2 = "\\b(?:[A-Za-z\\d-])+(?:\\.[A-Za-z0-9]+){0,3}\\." + "(?:" + commonTLDs + "|" + ccTLDs + ")" + "(?:\\." + ccTLDs + ")?(?=\\W|$)";
static String urlBody = "(?:[^\\.\\s<>][^\\s<>]*?)?";
static String urlExtraCrapBeforeEnd = "(?:" + punctChars + "|" + entity + ")+?";
static String urlEnd = "(?:\\.\\.+|[<>]|\\s|$)";
public static String url = "(?:" + urlStart1 + "|" + urlStart2 + ")" + urlBody + "(?=(?:" + urlExtraCrapBeforeEnd + ")?" + urlEnd + ")";
// Numeric
static String timeLike = "\\d+(?::\\d+){1,2}";
//static String numNum = "\\d+\\.\\d+";
static String numberWithCommas = "(?:(?<!\\d)\\d{1,3},)+?\\d{3}" + "(?=(?:[^,\\d]|$))";
static String numComb = "\\p{Sc}?\\d+(?:\\.\\d+)+%?";
// Abbreviations
static String boundaryNotDot = "(?:$|\\s|[“\\u0022?!,:;]|" + entity + ")";
static String aa1 = "(?:[A-Za-z]\\.){2,}(?=" + boundaryNotDot + ")";
static String aa2 = "[^A-Za-z](?:[A-Za-z]\\.){1,}[A-Za-z](?=" + boundaryNotDot + ")";
static String standardAbbreviations = "\\b(?:[Mm]r|[Mm]rs|[Mm]s|[Dd]r|[Ss]r|[Jj]r|[Rr]ep|[Ss]en|[Ss]t)\\.";
static String arbitraryAbbrev = "(?:" + aa1 + "|" + aa2 + "|" + standardAbbreviations + ")";
static String separators = "(?:--+|―|—|~|–|=)";
static String decorations = "(?:[♫♪]+|[★☆]+|[♥❤♡]+|[\\u2639-\\u263b]+|[\\ue001-\\uebbb]+)";
static String thingsThatSplitWords = "[^\\s\\.,?\"]";
static String embeddedApostrophe = thingsThatSplitWords + "+['’′]" + thingsThatSplitWords + "*";
public static String OR(String... parts) {
String prefix = "(?:";
StringBuilder sb = new StringBuilder();
for (String s : parts) {
sb.append(prefix);
prefix = "|";
sb.append(s);
}
sb.append(")");
return sb.toString();
}
// Emoticons
static String normalEyes = "(?iu)[:=]"; // 8 and x are eyes but cause problems
static String wink = "[;]";
static String noseArea = "(?:|-|[^a-zA-Z0-9 ])"; // doesn't get :'-(
static String happyMouths = "[D\\)\\]\\}]+";
static String sadMouths = "[\\(\\[\\{]+";
static String tongue = "[pPd3]+";
static String otherMouths = "(?:[oO]+|[/\\\\]+|[vV]+|[Ss]+|[|]+)"; // remove forward slash if http://'s aren't cleaned
// mouth repetition examples:
// @aliciakeys Put it in a love song :-))
// @hellocalyclops =))=))=)) Oh well
static String bfLeft = "(♥|0|o|°|v|\\$|t|x|;|\\u0CA0|@|ʘ|•|・|◕|\\^|¬|\\*)";
static String bfCenter = "(?:[\\.]|[_-]+)";
static String bfRight = "\\2";
static String s3 = "(?:--['\"])";
static String s4 = "(?:<|<|>|>)[\\._-]+(?:<|<|>|>)";
static String s5 = "(?:[.][_]+[.])";
static String basicface = "(?:(?i)" + bfLeft + bfCenter + bfRight + ")|" + s3 + "|" + s4 + "|" + s5;
static String eeLeft = "[＼\\\\ƪԄ\\(（<>;ヽ\\-=~\\*]+";
static String eeRight = "[\\-=\\);'\\u0022<>ʃ）/／ノﾉ丿╯σっµ~\\*]+";
static String eeSymbol = "[^A-Za-z0-9\\s\\(\\)\\*:=-]";
static String eastEmote = eeLeft + "(?:" + basicface + "|" + eeSymbol + ")+" + eeRight;
public static String emoticon = OR(
// Standard version :) :( :] :D :P
"(?:>|>)?" + OR(normalEyes, wink) + OR(noseArea, "[Oo]")
+ OR(tongue + "(?=\\W|$|RT|rt|Rt)", otherMouths + "(?=\\W|$|RT|rt|Rt)", sadMouths, happyMouths),
// reversed version (: D: use positive lookbehind to remove "(word):"
// because eyes on the right side is more ambiguous with the standard usage of : ;
"(?<=(?: |^))" + OR(sadMouths, happyMouths, otherMouths) + noseArea + OR(normalEyes, wink) + "(?:<|<)?",
//inspired by http://en.wikipedia.org/wiki/User:Scapler/emoticons#East_Asian_style
eastEmote.replaceFirst("2", "1"), basicface
// iOS 'emoji' characters (some smileys, some symbols) [\ue001-\uebbb]
// TODO should try a big precompiled lexicon from Wikipedia, Dan Ramage told me (BTO) he does this
);
static String Hearts = "(?:<+/?3+)+"; //the other hearts are in decorations
static String Arrows = "(?:<*[-―—=]*>+|<+[-―—=]*>*)|\\p{InArrows}+";
// BTO 2011-06: restored Hashtag, AtMention protection (dropped in original scala port) because it fixes
// "hello (#hashtag)" ==> "hello (#hashtag )" WRONG
// "hello (#hashtag)" ==> "hello ( #hashtag )" RIGHT
// "hello (@person)" ==> "hello (@person )" WRONG
// "hello (@person)" ==> "hello ( @person )" RIGHT
// ... Some sort of weird interaction with edgepunct I guess, because edgepunct
// has poor content-symbol detection.
// This also gets #1 #40 which probably aren't hashtags .. but good as tokens.
// If you want good hashtag identification, use a different regex.
static String Hashtag = "#[a-zA-Z0-9_]+"; //optional: lookbehind for \b
//optional: lookbehind for \b, max length 15
static String AtMention = "[@＠][a-zA-Z0-9_]+";
// I was worried this would conflict with at-mentions
// but seems ok in sample of 5800: 7 changes all email fixes
// http://www.regular-expressions.info/email.html
static String Bound = "(?:\\W|^|$)";
public static String Email = "(?<=" + Bound + ")[a-zA-Z0-9._%+-]+@[a-zA-Z0-9.-]+\\.[a-zA-Z]{2,4}(?=" + Bound + ")";
// We will be tokenizing using these regexps as delimiters
// Additionally, these things are "protected", meaning they shouldn't be further split themselves.
static Pattern Protected = Pattern.compile(
OR(
Hearts,
url,
Email,
timeLike,
//numNum,
numberWithCommas,
numComb,
emoticon,
Arrows,
entity,
punctSeq,
arbitraryAbbrev,
separators,
decorations,
embeddedApostrophe,
Hashtag,
AtMention
));
// Edge punctuation
// Want: 'foo' => ' foo '
// While also: don't => don't
// the first is considered "edge punctuation".
// the second is word-internal punctuation -- don't want to mess with it.
// BTO (2011-06): the edgepunct system seems to be the #1 source of problems these days.
// I remember it causing lots of trouble in the past as well. Would be good to revisit or eliminate.
// Note the 'smart quotes' (http://en.wikipedia.org/wiki/Smart_quotes)
static String edgePunctChars = "'\"“”‘’«»{}\\(\\)\\[\\]\\*&"; //add \\p{So}? (symbols)
static String edgePunct = "[" + edgePunctChars + "]";
static String notEdgePunct = "[a-zA-Z0-9]"; // content characters
static String offEdge = "(^|$|:|;|\\s|\\.|,)"; // colon here gets "(hello):" ==> "( hello ):"
static Pattern EdgePunctLeft = Pattern.compile(offEdge + "(" + edgePunct + "+)(" + notEdgePunct + ")");
static Pattern EdgePunctRight = Pattern.compile("(" + notEdgePunct + ")(" + edgePunct + "+)" + offEdge);
public static String splitEdgePunct(String input) {
Matcher m1 = EdgePunctLeft.matcher(input);
input = m1.replaceAll("$1$2 $3");
m1 = EdgePunctRight.matcher(input);
input = m1.replaceAll("$1 $2$3");
return input;
}
private static class Pair<T1, T2> {
public T1 first;
public T2 second;
public Pair(T1 x, T2 y) {
first = x;
second = y;
}
}
// The main work of tokenizing a tweet.
private static List<String> simpleTokenize(String text) {
// Do the no-brainers first
String splitPunctText = splitEdgePunct(text);
int textLength = splitPunctText.length();
// BTO: the logic here got quite convoluted via the Scala porting detour
// It would be good to switch back to a nice simple procedural style like in the Python version
// ... Scala is such a pain. Never again.
// Find the matches for subsequences that should be protected,
// e.g. URLs, 1.0, U.N.K.L.E., 12:53
Matcher matches = Protected.matcher(splitPunctText);
//Storing as List[List[String]] to make zip easier later on
List<List<String>> bads = new ArrayList<List<String>>(); //linked list?
List<Pair<Integer, Integer>> badSpans = new ArrayList<Pair<Integer, Integer>>();
while (matches.find()) {
// The spans of the "bads" should not be split.
if (matches.start() != matches.end()) { //unnecessary?
List<String> bad = new ArrayList<String>(1);
bad.add(splitPunctText.substring(matches.start(), matches.end()));
bads.add(bad);
badSpans.add(new Pair<Integer, Integer>(matches.start(), matches.end()));
}
}
// Create a list of indices to create the "goods", which can be
// split. We are taking "bad" spans like
// List((2,5), (8,10))
// to create
/// List(0, 2, 5, 8, 10, 12)
// where, e.g., "12" here would be the textLength
// has an even length and no indices are the same
List<Integer> indices = new ArrayList<Integer>(2 + 2 * badSpans.size());
indices.add(0);
for (Pair<Integer, Integer> p : badSpans) {
indices.add(p.first);
indices.add(p.second);
}
indices.add(textLength);
// Group the indices and map them to their respective portion of the string
List<List<String>> splitGoods = new ArrayList<List<String>>(indices.size() / 2);
for (int i = 0; i < indices.size(); i += 2) {
String goodstr = splitPunctText.substring(indices.get(i), indices.get(i + 1));
List<String> splitstr = Arrays.asList(goodstr.trim().split(" "));
splitGoods.add(splitstr);
}
// Reinterpolate the 'good' and 'bad' Lists, ensuring that
// additonal tokens from last good item get included
List<String> zippedStr = new ArrayList<String>();
int i;
for (i = 0; i < bads.size(); i++) {
zippedStr = addAllnonempty(zippedStr, splitGoods.get(i));
zippedStr = addAllnonempty(zippedStr, bads.get(i));
}
zippedStr = addAllnonempty(zippedStr, splitGoods.get(i));
// BTO: our POS tagger wants "ur" and "you're" to both be one token.
// Uncomment to get "you 're"
/*ArrayList<String> splitStr = new ArrayList<String>(zippedStr.size());
for(String tok:zippedStr)
splitStr.addAll(splitToken(tok));
zippedStr=splitStr;*/
return zippedStr;
}
private static List<String> addAllnonempty(List<String> master, List<String> smaller) {
for (String s : smaller) {
String strim = s.trim();
if (strim.length() > 0) {
master.add(strim);
}
}
return master;
}
/**
* "foo bar " => "foo bar"
*/
public static String squeezeWhitespace(String input) {
return Whitespace.matcher(input).replaceAll(" ").trim();
}
// Final pass tokenization based on special patterns
private static List<String> splitToken(String token) {
Matcher m = Contractions.matcher(token);
if (m.find()) {
String[] contract = {m.group(1), m.group(2)};
return Arrays.asList(contract);
}
String[] contract = {token};
return Arrays.asList(contract);
}
/**
* Assume 'text' has no HTML escaping. *
*/
public static List<String> tokenize(String text) {
return simpleTokenize(squeezeWhitespace(text));
}
/**
* Twitter text comes HTML-escaped, so unescape it. We also first unescape
* &'s, in case the text has been buggily double-escaped.
*
* @param text
* @return
*/
public static String normalizeTextForTagger(String text) {
text = text.replaceAll("&", "&");
text = StringEscapeUtils.unescapeHtml4(text);
return text;
}
/**
* This is intended for raw tweet text -- we do some HTML entity unescaping
* before running the tagger.
*
* This function normalizes the input text BEFORE calling the tokenizer. So
* the tokens you get back may not exactly correspond to substrings of the
* original text.
*/
public static List<String> tokenizeRawTweetText(String text) {
List<String> tokens = tokenize(normalizeTextForTagger(text));
return tokens;
}
/**
* Tokenizes tweet texts on standard input, tokenizations on standard
* output. Input and output UTF-8.
*/
/*public static void main(String[] args) throws IOException {
BufferedReader input = new BufferedReader(new InputStreamReader(System.in, "UTF-8"));
PrintStream output = new PrintStream(System.out, true, "UTF-8");
String line;
while ((line = input.readLine()) != null) {
List<String> toks = tokenizeRawTweetText(line);
for (int i = 0; i < toks.size(); i++) {
output.print(toks.get(i));
if (i < toks.size() - 1) {
output.print(" ");
}
}
output.print("\n");
}
}*/
}