Replacing quotes in a Java String only on specific places

Question

We have a String as below.

\config\test\[name="sample"]\identifier["2"]\age["3"]

I need to remove the quotes surrounding the numbers. For example, the above string after replacement should look like below.

\config\test\[name="sample"]\identifier[2]\age[3]

Currently I'm trying with the regex as below

String.replaceAll("\"\\\\d\"", "");

This is replacing the numbers also. Please help to find out a regex for this.

Hello and welcome to StackOverflow. Please take some time to read the help page, especially the sections named ["What topics can I ask about here?"](http://stackoverflow.com/help/on-topic) and ["What types of questions should I avoid asking?"](http://stackoverflow.com/help/dont-ask). And more importantly, please read [the Stack Overflow question checklist](http://meta.stackexchange.com/q/156810/204922). You might also want to learn about [Minimal, Complete, and Verifiable Examples](http://stackoverflow.com/help/mcve). — Esteban P., Jul 10 '17 at 07:30
Please also pay attention to the big orange **How to Format** box to the right of the text area (when you're initially asking the question), entire toolbar full of formatting aids, **[?]** button giving formatting help, and post preview area. Making your post clear, and demonstrating that you took the time to do so, improves your chances of getting good answers. — T.J. Crowder, Jul 10 '17 at 07:33
Possible duplicate of https://stackoverflow.com/questions/36267354/java-string-replaceall-with-back-reference — JSN, Jul 10 '17 at 07:36

score 1 · Accepted Answer · edited Sep 23 '17 at 23:31

1

You can use replaceAll with this regex \"(\d+)\" so you can replace the matching of \"(\d+)\" with the capturing group (\d+) :

String str = "\\config\\test\\[name=\"sample\"]\\identifier[\"2\"]\\age[\"3\"]";
str = str.replaceAll("\"(\\d+)\"", "$1");
//----------------------^____^------^^

Output

\config\test\[name="sample"]\identifier[2]\age[3]

regex demo

Take a look about Capturing Groups

edited Sep 23 '17 at 23:31

Graham

7,431
18
59
84

answered Jul 10 '17 at 07:33

Youcef LAIDANI

55,661
15
90
140

1

How does it work? Code dumps are not useful answers. – T.J. Crowder Jul 10 '17 at 07:34
what did you mean @T.J.Crowder i think i use a basic regex no? – Youcef LAIDANI Jul 10 '17 at 07:38
Well, the OP wasn't able to come up with it, so some explanation of what it does would make sense. Teach a man to fish and all that. – T.J. Crowder Jul 10 '17 at 07:41
thank you @T.J.Crowder what about the new version i agree the first version was not clear – Youcef LAIDANI Jul 10 '17 at 07:42
1

Thanks YCF_L. It worked with the regex mentioned. I was missing to use "$1" in the replacement. Thanks a lot. – ganesh Jul 10 '17 at 07:45

Tim Biegeleisen · Answer 2 · 2017-07-10T07:42:33.310

1

We can try doing a blanket replacement of the following pattern:

\["(\d+)"\]

And replacing it with this:

\[$1\]

Note that we specifically target quoted numbers only appearing in square brackets. This minimizes the risk of accidentally doing an unintended replacement.

Code:

String input = "\\config\\test\\[name=\"sample\"]\\identifier[\"2\"]\\age[\"3\"]";
input = input.replaceAll("\\[\"(\\d+)\"\\]", "[$1]");
System.out.println(input);

Output:

\config\test\[name="sample"]\identifier[2]\age[3]

Demo here:

Rextester

edited Jul 10 '17 at 07:42

answered Jul 10 '17 at 07:36

Tim Biegeleisen

502,043
27
286
360

Thanks Tim for the detailed explanation. It worked. Thanks a lot. – ganesh Jul 10 '17 at 07:44

Shakiba Moshiri · Answer 3 · 2017-07-10T10:11:27.020

You can use:

(?:"(?=\d)|(?<=\d)")

and replace it with nothing == ( "" )

fast test:

echo '\config\test\[name="sample"]\identifier["2"]\age["3"]' | perl -lpe 's/(?:"(?=\d)|(?<=\d)")//g'

the output:

\config\test\[name="sample"]\identifier[2]\age[3]

test2:

echo 'identifier["123"]\age["456"]' | perl -lpe 's/(?:"(?=\d)|(?<=\d)")//g'

the output:

identifier[123]\age[456]

NOTE

if you have only a single double quote " it works fine; otherwise you should add quantifier + for both beginning and end "

test3:

echo '"""""1234234"""""' | perl -lpe 's/(?:"+(?=\d)|(?<=\d)"+)//g'

the output:

Replacing quotes in a Java String only on specific places

3 Answers3

regex demo

Rextester