RegEx for capturing particular digits

Question

From the below logs how can i grep '951792' values alone

2019 May 22 03:32:17.952296 france1v4 sh[4937]: 190522-03:32:17.951792 [mod=REC, lvl=INFO] [tid=26130] Recording A8602096210405800406L200218680503121519 size is 4145956224 bytes
2019 May 22 03:32:17.952387 france1v4 sh[4937]: 190522-03:32:17.951895 [mod=REC, lvl=INFO] [tid=26130] RecordingInfo = fffocap://0x401e
2019 May 22 03:32:17.952466 france1v4 sh[4937]: 190522-03:32:17.951934 [mod=REC, lvl=INFO] [tid=26130] recording_dvr_from_recording_info:physicalSegmentCount=10   

I tried with java split/substring operations. but line of code is high. using regex how can i get '951792' values

The output will be

951792
951895
951934 
075041

Answer 1

Here, we might want to simply use the right boundary [mod next to our desired digits and collect the digits in our first capturing group, maybe similar to this:

([0-9]+)\s\[m 

If we wish, we can add more boundaries, such as:

(.+?)([0-9]+)\s\[m.+

DEMO

Test

import java.util.regex.Matcher;
import java.util.regex.Pattern;

final String regex = "(.+?)([0-9]+)\\s\\[m.+";
final String string = "2019 May 22 03:32:17.952296 france1v4 sh[4937]: 190522-03:32:17.951792 [mod=REC, lvl=INFO] [tid=26130] Recording A8602096210405800406L200218680503121519 size is 4145956224 bytes\n"
     + "2019 May 22 03:32:17.952387 france1v4 sh[4937]: 190522-03:32:17.951895 [mod=REC, lvl=INFO] [tid=26130] RecordingInfo = fffocap://0x401e\n"
     + "2019 May 22 03:32:17.952466 france1v4 sh[4937]: 190522-03:32:17.951934 [mod=REC, lvl=INFO] [tid=26130] recording_dvr_from_recording_info:physicalSegmentCount=10   \n";
final String subst = "\\2";

final Pattern pattern = Pattern.compile(regex, Pattern.MULTILINE);
final Matcher matcher = pattern.matcher(string);

// The substituted value will be contained in the result variable
final String result = matcher.replaceAll(subst);

System.out.println("Substitution result: " + result);

Demo

const regex = /(.+?)([0-9]+)\s\[m.+/gm;
const str = `2019 May 22 03:32:17.952296 france1v4 sh[4937]: 190522-03:32:17.951792 [mod=REC, lvl=INFO] [tid=26130] Recording A8602096210405800406L200218680503121519 size is 4145956224 bytes
2019 May 22 03:32:17.952387 france1v4 sh[4937]: 190522-03:32:17.951895 [mod=REC, lvl=INFO] [tid=26130] RecordingInfo = fffocap://0x401e
2019 May 22 03:32:17.952466 france1v4 sh[4937]: 190522-03:32:17.951934 [mod=REC, lvl=INFO] [tid=26130] recording_dvr_from_recording_info:physicalSegmentCount=10   
`;
const subst = `$2`;

// The substituted value will be contained in the result variable
const result = str.replace(regex, subst);

console.log('Substitution result: ', result);

RegEx

If this expression wasn't desired, it can be modified or changed in regex101.com.

RegEx Circuit

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