How to split paragraphs into sentences?

Question

Please have a look at the following.

String[]sentenceHolder = titleAndBodyContainer.split("\n|\\.(?!\\d)|(?<!\\d)\\.");

This is how I tried to split a paragraph into sentences. But, there is a problem. My paragraph includes dates like Jan. 13, 2014, words like U.S and numbers like 2.2. They all got splitted by the above code. So basically, this code splits lot of 'dots' whether it is a full stop or not.

I tried String[]sentenceHolder = titleAndBodyContainer.split(".\n"); and String[]sentenceHolder = titleAndBodyContainer.split("\\."); as well. All failed.

How can I split a paragraph into sentences "properly"?

Look at using a sentence [BreakIterator](http://docs.oracle.com/javase/tutorial/i18n/text/about.html) — greg-449, Jan 29 '14 at 12:00
You can start by defining `properly` in terms that the computer can understand. — Keppil, Jan 29 '14 at 12:01
http://stackoverflow.com/questions/17654738/regex-split-text-document-into-sentences — StoopidDonut, Jan 29 '14 at 12:02
This is not a trivial task, phew... E.g. the sentence "In Sweden a common name is Jan. 31, at least, people have this name.", would be virtually impossible to parse, without some kind of context aware parser. (Edit: "Jan" **is** a common christian name in Sweden ;)) — SamWhan, Jan 29 '14 at 12:24
http://stackoverflow.com/questions/4674850/converting-a-sentence-string-to-a-string-array-of-words-in-java — james.garriss, Oct 28 '15 at 15:43

score 19 · Answer 1 · edited Mar 06 '17 at 11:00

19

You can try this

String str = "This is how I tried to split a paragraph into a sentence. But, there is a problem. My paragraph includes dates like Jan.13, 2014 , words like U.S and numbers like 2.2. They all got split by the above code.";

Pattern re = Pattern.compile("[^.!?\\s][^.!?]*(?:[.!?](?!['\"]?\\s|$)[^.!?]*)*[.!?]?['\"]?(?=\\s|$)", Pattern.MULTILINE | Pattern.COMMENTS);
Matcher reMatcher = re.matcher(str);
while (reMatcher.find()) {
    System.out.println(reMatcher.group());
}

Output:

This is how I tried to split a paragraph into a sentence.
But, there is a problem.
My paragraph includes dates like Jan.13, 2014 , words like U.S and numbers like 2.2.
They all got split by the above code.

edited Mar 06 '17 at 11:00

Manfred Radlwimmer

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answered Jan 29 '14 at 12:12

Ruchira Gayan Ranaweera

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Hmm... Where did the space after "Jan." go... What a mystery ;) – SamWhan Jan 29 '14 at 13:20
What does the regex mean? I'm newbie at java, I'm interested to learn about your regex :-( – sreffejnnayr Dec 28 '15 at 09:55
1

@Wingzero Please refer theses. https://docs.oracle.com/javase/7/docs/api/java/util/regex/Pattern.html; http://www.regular-expressions.info/modifiers.html – Ruchira Gayan Ranaweera Dec 28 '15 at 15:01
What initiates the `\n` in the regex to split sentences? Is using .MULTILINE and .COMMENTS really necessary? – sreffejnnayr Dec 28 '15 at 16:52
1

@UtherPendragon, this solution http://stackoverflow.com/a/2687929/462347 can deal with the «`U.S. `» case. – Mike Apr 15 '16 at 15:36

score 1 · Answer 2 · edited Mar 06 '17 at 11:01

1

String[] sentenceHolder = titleAndBodyContainer.split("(?i)(?<=[.?!])\\S+(?=[a-z])");

Try this it worked for me.

edited Mar 06 '17 at 11:01

Manfred Radlwimmer

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answered Jan 29 '14 at 12:10

Sathesh

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score 0 · Answer 3 · edited Mar 06 '17 at 10:59

0

This will split the paragraph by . ? !:

String a[]=str.split("\\.|\\?|\\!");

You can put any symbol after \\ which you want to use and use | to separate each condition.

edited Mar 06 '17 at 10:59

Manfred Radlwimmer

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answered Mar 06 '17 at 10:57

Manas Kandekar

1

why not split("[.?!]") ? – Kamil Naja Oct 04 '20 at 13:47

How to split paragraphs into sentences?

3 Answers3

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