Java regex for inserting text between braces

Question

I have a String

a = "stringWithBraces()"

I want to create the following string

"stringWithBraces(text)"

How do I achieve this using regex?

I tried this :

a.replaceAll("\\(.+?\\)", "text");

But get this :

stringWithBraces()

do you mean you wanna achieve something like: String first = "(abc)"; String myVariable = "def"; to become String first = "abc(def)"? — Yahya, Apr 21 '17 at 20:11
Why not use a literal replacement? `.replace("()", "(" + text + ")")`? Note there is nothing wrong with the `"(" + text + ")"`. — Wiktor Stribiżew, Apr 21 '17 at 20:19

vallentin · Answer 1 · 2017-04-21T20:31:51.710

1

You can use lookaheads and do something like this:

(?<=\().*?(?=\))

Live Demo

Thus doing this:

String a = "stringWithBraces()";
a = a.replaceAll("(?<=\\().*?(?=\\))", Matcher.quoteReplacement("text"));

System.out.println(a);

Outputs:

stringWithBraces(text)

Note that in relation to replaceAll() then the replacement string has some special character. So you should most likely use Matcher.quoteReplacement() in order to escape those and be safe.

edited Apr 21 '17 at 20:31

answered Apr 21 '17 at 20:17

vallentin

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Note that the `"text"` is in fact a variable. And a string variable may contain special chars that are treated specifically in a replacement pattern. – Wiktor Stribiżew Apr 21 '17 at 20:18
@WiktorStribiżew thanks forgot about that. It's fixed now. – vallentin Apr 21 '17 at 20:25

score 0 · Answer 2 · answered Apr 21 '17 at 19:57

0

You can use this :

a = a.replaceAll("\\((.*?)\\)", "(text)");

You have to replace every thing between parenthesis with (text)

answered Apr 21 '17 at 19:57

Youcef LAIDANI

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hmm I was trying to avoid "(" + variable + ")" – user_mda Apr 21 '17 at 20:00
what did you mean @user_mda ? – Youcef LAIDANI Apr 21 '17 at 20:01
'text' in my question is a variable. So I didnt want to append "(" + variable + ")" but just replace what is between the braces with the variable – user_mda Apr 21 '17 at 20:07
1

why you want to avoid this solution @user_mda ? – Youcef LAIDANI Apr 21 '17 at 20:22

score 0 · Answer 3 · answered Apr 21 '17 at 20:33

+ requires at least one char, the ? added here means the shortest match, so "...(.)...(.)..." would not continue to find ".)...(.".

a.replaceAll("\\(.*?\\)", "(text)");

You might have intended replaceFirst; though I think not.

You might also let the dot . match new line chars, for mult-line matches, using the DOT_ALL option (?s):

a.replaceAll("(?s)\\(.*?\\)", "(text)");

Java regex for inserting text between braces

3 Answers3