regex101: Java Match Workspace

Pro

1st Alternative^(20[1-5]\d)-(0?[1-9]|1[012])-(0?[1-9]|[12]\d|3[01])\s([0-1]\d)

^start of line

Group 1(20[1-5]\d)

20the literal text 20

Character Class[1-5]

1-5one character from 1 (49₁₀) to 5 (53₁₀)

\da digit

-the literal - (45₁₀ / 55₈ / 2D₁₆)

Group 2(0?[1-9]|1[012])

1st Alternative0?[1-9]

0?optionally matches the literal 0 (48₁₀ / 60₈ / 30₁₆)

Character Class[1-9]

1-9one character from 1 (49₁₀) to 9 (57₁₀)

2nd Alternative1[012]

1the literal 1 (49₁₀ / 61₈ / 31₁₆)

Character Class[012]

0the literal 0 (48₁₀ / 60₈ / 30₁₆)

1the literal 1 (49₁₀ / 61₈ / 31₁₆)

2the literal 2 (50₁₀ / 62₈ / 32₁₆)

-the literal - (45₁₀ / 55₈ / 2D₁₆)

Group 3(0?[1-9]|[12]\d|3[01])

1st Alternative0?[1-9]

0?optionally matches the literal 0 (48₁₀ / 60₈ / 30₁₆)

Character Class[1-9]

1-9one character from 1 (49₁₀) to 9 (57₁₀)

2nd Alternative[12]\d

Character Class[12]

1the literal 1 (49₁₀ / 61₈ / 31₁₆)

2the literal 2 (50₁₀ / 62₈ / 32₁₆)

\da digit

3rd Alternative3[01]

3the literal 3 (51₁₀ / 63₈ / 33₁₆)

Character Class[01]

0the literal 0 (48₁₀ / 60₈ / 30₁₆)

1the literal 1 (49₁₀ / 61₈ / 31₁₆)

\sany whitespace character

Group 4([0-1]\d)

Character Class[0-1]

0-1one character from 0 (48₁₀) to 1 (49₁₀)

\da digit

2nd Alternative(2[0-3]):([0-5]\d):([0-5]\d)$

Group 5(2[0-3])

2the literal 2 (50₁₀ / 62₈ / 32₁₆)

Character Class[0-3]

0-3one character from 0 (48₁₀) to 3 (51₁₀)

:the literal : (58₁₀ / 72₈ / 3A₁₆)

Group 6([0-5]\d)

Character Class[0-5]

0-5one character from 0 (48₁₀) to 5 (53₁₀)

\da digit

:the literal : (58₁₀ / 72₈ / 3A₁₆)

Group 7([0-5]\d)

Character Class[0-5]

0-5one character from 0 (48₁₀) to 5 (53₁₀)

\da digit

$end of line

Global pattern flags

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

27 tokens

Regular Expression

^(20[1-5]\d)-(0?[1-9]|1[012])-(0?[1-9]|[12]\d|3[01])\s([0-1]\d)|(2[0-3]):([0-5]\d):([0-5]\d)$

New

2022-11-02 00:00:00 bla..
2022-11-02 19:00:00 bla..
..something else 20:00:00

Substitution

2022-11-02 00:00:00 bla..
2022-11-02 19:00:00 bla..
..something else 20:00:00