How to use regular expressions to replace multiple occurrences of non-consecutive characters?

Question

Java

1. Given a card number:
1234 5678 9999 0000
What is the best way to convert it to:
**** ***** ***** 0000
Using only regular expressions?
2. A random string is given, for example: It is
ABC123PPE553QQ999
necessary to replace the first five digits , for example:
ABC***PPE**3QQ999
Do I understand correctly that it is impossible to do this using regular expressions?

Answer 1

Why is the second one not possible?
Are looking for
replace with
The first five capture groups are filled with either nothing or any number of non-digits. Last - the remainder of the line after the last digit. It is assumed that there are always at least five digits in a string.