Replacing all consecutive "\r\n or \n"s with one single

Question

Currently I am showing messages that I get from DB using only these two replacements:

text = text.replace("\r\n", "<br />");
text = text.replace("\n", "<br />");

but the problem is if there are many consecutive "\n"s I will have lots of
s or white spaces, I just want to make them all one. So what is your suggestion? Is there a quick replace method to make all consecutive \n\n\n\n\n\n\n only one just one br?

Rohit Jain · Accepted Answer · 2012-10-05T17:15:12.323

6

You can use quantifier + to denote 1 or more.. Also, * means 0 or more..

text = text.replaceAll("\n+", "<br />");

text = text.replaceAll("[\n\r]+", "<br />");

edited Oct 05 '12 at 17:15

answered Oct 05 '12 at 17:01

Rohit Jain

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Thanks and if its \r\n or \n it will be text = text.replace("\n+|\n\r+", "
"); ? – Jimmy Page Oct 05 '12 at 17:02
@NullUserException.. Why?? And which one first or second?? – Rohit Jain Oct 05 '12 at 17:03
@RohitJain The second, but you fixed it. – NullUserException Oct 05 '12 at 17:04
@NullUserException.. Now its better.. I used character class to denote `\n` or `\r`.. – Rohit Jain Oct 05 '12 at 17:05
`replace` doesn't accept regular expressions, `replaceAll` does. – Brian Oct 05 '12 at 17:05
@RohitJain Your second line makes the first one redundant. – NullUserException Oct 05 '12 at 17:07
@NullUserException.. Yeah.. Because it covers both.. Probably I would quote that.. – Rohit Jain Oct 05 '12 at 17:07
You probably meant `(\r\n)+`; `(\n+\r+)` (which in this case doesn't need the parens), matches a string of `\n` characters followed by a string of `\r`s. `(\n|\r)+` behaves like the third regex, only less efficiently. – NullUserException Oct 05 '12 at 17:15
@NullUserException Edited code.. That works.. Actually 2nd and 3rd were same... So, removed the 2nd.. – Rohit Jain Oct 05 '12 at 17:16

score 2 · Answer 2 · answered Oct 05 '12 at 17:04

2

If you have multiple \r\n or \n with other content in between, you may also use

text.replaceAll("(\r\n)+", "<br />")
    .replaceAll("\n+", "<br />");

answered Oct 05 '12 at 17:04

Cory Kendall

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score 1 · Answer 3 · answered Oct 05 '12 at 17:02

1

Have you tried this:

text = text.replace("(\r\n)+", "<br />");
text = text.replace("\n+", "<br />");

The + means "one or more" of the preceding match.

answered Oct 05 '12 at 17:02

gpojd

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Replacing all consecutive "\r\n or \n"s with one single

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