\ba Unicode word boundary
Dthe literal D (6810 / 1048 / 4416) (case sensitive)
\s*a Unicode whitespace character, repeated any number of times
\.the literal . (4610 / 568 / 2E16)
\s*a Unicode whitespace character, repeated any number of times
Othe literal O (7910 / 1178 / 4F16) (case sensitive)
\s*a Unicode whitespace character, repeated any number of times
\.the literal . (4610 / 568 / 2E16)
\s*a Unicode whitespace character, repeated any number of times
Bthe literal B (6610 / 1028 / 4216) (case sensitive)
Negated Character Class[^:]* *matches any number of characters outside the set below:
:the literal : (5810 / 728 / 3A16)
:the literal : (5810 / 728 / 3A16)
\s+a Unicode whitespace character, repeated at least once
Group 1(\d{1,2}\s*(?:JAN|NOV|OCT|DEC|J\s*u\s*n\s*e)(?:\s*\d){4}) \d{1,2}a Unicode decimal digit, repeated between 1 and 2 times
\s*a Unicode whitespace character, repeated any number of times
Non-Capturing Group(?:JAN|NOV|OCT|DEC|J\s*u\s*n\s*e) JANthe literal text JAN (case sensitive) NOVthe literal text NOV (case sensitive) OCTthe literal text OCT (case sensitive) DECthe literal text DEC (case sensitive) 5th AlternativeJ\s*u\s*n\s*e Jthe literal J (7410 / 1128 / 4A16) (case sensitive)
\s*a Unicode whitespace character, repeated any number of times
uthe literal u (11710 / 1658 / 7516) (case sensitive)
\s*a Unicode whitespace character, repeated any number of times
nthe literal n (11010 / 1568 / 6E16) (case sensitive)
\s*a Unicode whitespace character, repeated any number of times
ethe literal e (10110 / 1458 / 6516) (case sensitive)
Non-Capturing Group(?:\s*\d){4} {4}repeats the group contents below exactly 4 times:
\s*a Unicode whitespace character, repeated any number of times
\da Unicode decimal digit
g modifier: global. Finds all matches instead of stopping after the first
m modifier: multiline. Causes ^ and $ to match the start and end of each line, not only the start and end of the string