电子邮件屏蔽的正则表达式

Question

I am trying to write a regular expression to mask an email address. Example below.

input: john.doe@example.en.com

output: j*******@e*********.com

I have tried the following but I just can't seem to get it working correctly.

regex: (?<=.).(?=[^@]\\*?@)

output:j*******@example.en.com

regex: (?<=.).(?=[^@]\\*?)(?=[^\\.]\\*?\\.)

output:j******************.com

Any help would be appreciated. demo

Answer 1

Update with various masking email solutions

• foo@bar.com ⇒ f**@b**.com (current question) - s.replaceAll("(?<=.)[^@](?=[^@]*?@)|(?:(?<=@.)|(?!^)\\\\G(?=[^@]*$)).(?=.*\\\\.)", "*") (see the regex demo )

• foo@bar.com ⇒ f**@b*r.com - s.replaceAll("(?<=.)[^@](?=[^@]*?@)|(?:(?<=@.)|(?!^)\\\\G(?=[^@]*$)).(?=.*[^@]\\\\.)", "*") (see the regex demo )

• foo@bar.com ⇒ f*o@b*r.com - s.replaceAll("(?<=.)[^@](?=[^@]*?[^@]@)|(?:(?<=@.)|(?!^)\\\\G(?=[^@]*$)).(?=.*[^@]\\\\.)", "*") (see the regex demo )

• foo@bar.com ⇒ f**@b*****m - s.replaceAll("(?<=.)[^@](?=[^@]*?@)|(?:(?<=@.)|(?!^)\\\\G(?=[^@]*$)).(?!$)", "*") (see the regex demo )

• foo@bar.com ⇒ f*o@b*****m - s.replaceAll("(?<=.)[^@](?=[^@]*[^@]@)|(?:(?<=@.)|(?!^)\\\\G(?=[^@]*$)).(?!$)", "*") (see the regex demo )

Original answer

In case you can't use a code-based solution, you may use

s.replaceAll("(?<=.)[^@](?=[^@]*?@)|(?:(?<=@.)|(?!^)\\G(?=[^@]*$)).(?=.*\\.)", "*")

See the regex demo

What it does :

• (?<=.)[^@](?=[^@]*?@) -any char other than @ ( [^@] ) that is preceded by any single char ( (?<=.) ) and is followed with any 0 or more chars other than @ up to a @ ( (?=[^@]*?@) )
• | - or
• (?:(?<=@.)|(?!^)\\\\G(?=[^@]*$)) - match a location in the string that is preceded with @ and any char ( (?<=@.) ) or ( | ) the end of the previous successful match ( (?!^)\\\\G ) that is followed with any 0+ chars other than @ uo to the end of string ( (?=[^@]*$) )
• . - any single char
• (?=.*\\\\.) - followed with any 0+ chars up to the last . symbol in the string.

Answer 2

How about this one if you do not need the masks having the same number of characters of the original strings (which is more anonymous):

(?<=^.)[^@]*|(?<=@.).*(?=\.[^.]+$)

For example, if you replace the matches with *** , the result would be:

j***@e***.com