Question

I need to replace a string that could have one or more blank space in its content (at a fixed position) with another string.

e.g:

[   string   ] 

must be replaced with:

anotherstring

(where there could be more or less or none blank spaces between ” and string). And also the replacement must be case insenitive. Actually i’m using that expression:

myString.replaceAll("[(?i)string]", "anotherstring"); 

but this only works if there aren’t spaces between brackets and string.
How can i build an expression to consider also whitespaces?

Answer 1

If you want to allow any whitespace use:

myString.replaceAll("\\[\\s*(?i)string\\s*\\]", "anotherstring"); 

If you want to allow only spaces use:

myString.replaceAll("\\[ *(?i)string *\\]", "anotherstring"); 

Note that you’ve not escaped the [ and ] in your regex. [ and ] are regex meta-characters that mark the start and end of a character class respectively.

So a [(?i)string] matches a single character that is one of (, ?, i, ), s, t, r, i, n or g

To match them literally they need to be escaped by placing a \\ before them.