why is regex ^[0-9][0-9][0-9][0-9] failing when checking '1446'. works in java regex checker

rob.zimmelman

using regex validator against a field containing a 4 digit number (hour and minute of day), number is '1446', using  ^[0-9][0-9][0-9][0-9] and it is failing.  when i try the same in https://www.freeformatter.com/java-regex-tester.html#ad-output or in python 're' module, e.g. it works.

Thomas Deiler_db00h3

Dear @rob.zimmelman ,

I have no answer for your question, but dose this RegEx work?

[0-2][0-9][0-5][0-9]

I have proved this RegEx with following Java code:

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

public class Main {
public static void main(String[] args) {
Pattern pattern = Pattern.compile("[0-2][0-9][0-5][0-9]", Pattern.CASE_INSENSITIVE);
Matcher matcher = pattern.matcher("1446");
boolean matchFound = matcher.find();
if(matchFound) {
System.out.println("Match found");
} else {
System.out.println("Match not found");
}
}
}

So long

Thomas