Regular Expression

expression	description
[abc]	A single character of: a, b or c
[^abc]	A character except: a, b or c
[a-z]	A character in range: a-z
[^a-z]	A character not in the range: a-z
[0-9]	A digit in the range: 0-9
[a-zA-Z]	A character in the range: a-z or A-Z
[a-zA-Z0-9]	A character in the range: a-z, A-Z or 0-9
a?	Zero or one of a
a*	Zero or more of a
a+	One or more of a
[0-9]+	One or more of 0-9
a{3}	Exactly 3 of a
a{3,}	3 or more of a
a{3,6}	Between 3 and 6 of a
.	Any single character
\s	Any whitespace character
\S	Any non-whitespace character
\d	Any digit, Same as [0-9]
\D	Any non-digit, Same as [^0-9]
\w	Any word character
\W	Any non-word character
\G	Start of match
^	Start of string
$	End of string
\A	Start of string
\Z	End of string
\z	Absolute end of string
\t	Tab
\n	New line

JSON 형식
- Ex. expiry: ~~~
- \"expiry\"\s*:\s* \"(.*?)\"
- 로그백을 통한 민감정보 마스킹 시 주로 사용

in Kotlin

"".replace("\\{\\{userId}}".toRegex(), "Replace Value")