The following patterns should be matched: - AAA123 - ABCDEFGH123 - XXXX123 Can I use `".*123"` to achieve this?

General Discussions
#1

The following patterns should be matched:

  • AAA123
  • ABCDEFGH123
  • XXXX123

Can I use ".*123" to achieve this?

#2

Hey Arpanaa,

Yes, you can use ".*123". In regular expressions:

  • . matches any character except a newline.
  • .* matches any character (except newline) zero or more times.
  • 123 matches the literal characters “123”.

So, .*123 will match any string that ends with “123”, preceded by any number of characters.

#3

Hey Arpanaa,

Yes, that will work. However, note that the . in a regular expression does not match newline characters by default. If you want it to match newline characters, use the Pattern.DOTALL flag when compiling the pattern. Here’s how you can do it:

Pattern pattern = Pattern.compile(“.*123”, Pattern.DOTALL); Matcher matcher = pattern.matcher(inputStr); boolean matchFound = matcher.matches();

This will create a pattern that matches any character (including newlines) zero or more times, followed by “123”.

Hope this works for you.

#4

Hey @richaaroy

Just to add up to the your answer,

For the specific problem of matching strings ending with “123” and possibly containing uppercase letters before it:

To match “123”, “AAA123”, and “ASDFRRF123”, you can use [A-Z]*123$. If you need at least one character before “123”, use [A-Z]+123$.

For a more general solution to matching “any character” in a regular expression:

  • To match anything including whitespace, you can use [\w|\W]{min_char_to_match,}.
  • To match anything except whitespace, you can use [\S]{min_char_to_match,}.