java.util.regex.PatternSyntaxException: Unclosed character class near index 44

Question

Here is my code to look for adjacent words around a proper noun. I get an error for this code mentioned below. I've tried adding different permutations and combinations of backslashes and closing brackets but still get the error. Will appreciate help.

 for (String properNoun : properNouns){

             Pattern pattern = Pattern.compile("([^\\s]+\\s+[^\\s]+)\\s+"+properNoun+"\\s+([^\\s]+\\s+[^\\s]+)\\s+");
             Matcher matcher = pattern.matcher(sentence);

             while (matcher.find()){
................

The error I get is:

Exception in thread "main" java.util.regex.PatternSyntaxException:
Unclosed character class near index 44
([^\s]+\s+[^\s]+)\s+[]\s+([^\s]+\s+[^\s]+)\s+

Sentence - Cyprium Mining is pleased to announce that at a special meeting of debenture holders held on September 21 , 2016 ( the " Meeting " ) the holders of dollars 750,000 in principal_amount of unsecured debentures bearing interest at 12 % per_annum ( the " Debentures " ) overwhelmingly approved all matters presented , including the extension of the maturity_date from February 28 , 2017 to February 28 , 2019 .

properNouns - [[], [Cyprium], [February], [the Debentures], [September]]

It is not giving me any exception...could you share the values of properNouns and sentence? — Amber Beriwal
– Amber Beriwal, Commented Dec 26, 2016 at 8:36

chengpohi · Accepted Answer · 2016-12-26 08:52:18Z

3

properNoun value is [], this is a character class, it should contains some characters, if you want to match [], you should escape this, like: \\[\\].

As your data, maybe you can do it like:

Pattern pattern = Pattern.compile("([^\\s]+\\s+[^\\s]+)\\s+"+Pattern.quote(properNoun)+"\\s+([^\\s]+\\s+[^\\s]+)\\s+");

Pattern.quote:

Returns a literal pattern String for the specified String

edited Dec 26, 2016 at 8:52

answered Dec 26, 2016 at 8:41

chengpohi

14.2k1 gold badge28 silver badges43 bronze badges

Sign up to request clarification or add additional context in comments.

2 Comments

serendipity Over a year ago

I'm looping over proper nouns and they contain characters. Updated the question to add those values. The first value in my proper noun set is null..could that be the reason for the error?

chengpohi Over a year ago

@serendipity maybe you can use Pattern.quote to escape the str

Collectives™ on Stack Overflow

java.util.regex.PatternSyntaxException: Unclosed character class near index 44

1 Answer 1

2 Comments

Your Answer

Linked

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

2 Comments

Your Answer

Sign up or log in

Post as a guest

Linked

Related