Valid Username Regular Expression ⬀
You are updating the username policy on your company's internal networking platform. According to the policy, a username is considered valid if all the following constraints are satisfied:
- The username consists of
8to30characters inclusive. If the username consists of less than8or greater than30characters, then it is an invalid username. - The username can only contain alphanumeric characters and underscores (
_). Alphanumeric characters describe the character set consisting of lowercase characters[a-z], uppercase characters[A-Z], and digits[0-9]. - The first character of the username must be an alphabetic character, i.e.,
either lowercase character
[a-z]or uppercase character[A-Z].
For example:
| Username | Validity |
|---|---|
Julia |
INVALID; Username length < 8 characters |
Samatha |
VALID |
Samantha_21 |
VALID |
1Samantha |
INVALID; Username begins with non-alphabetic character |
Samantha?10_2A |
INVALID; '?' character not allowed |
Update the value of regularExpression field in the UsernameValidator class so that the regular expression only matches with valid usernames.
The first line of input contains an integer n, describing the total number
of usernames. Each of the next lines contains a string describing the username.
The locked stub code reads the inputs and validates the username.
1 ≤ N ≤ 100- The username consists of any printable characters.
For each of the usernames, the locked stub code prints Valid if the username
is valid; otherwise Invalid each on a new line.
8
Julia
Samantha
Samantha_21
1Samantha
Samantha?10_2A
JuliaZ007
Julia@007
_Julia007
Invalid
Valid
Valid
Invalid
Invalid
Valid
Invalid
Invalid
Refer diagram in the challenge statement.