Remove all special characters from a string except for digits and the degree symbol?

Question

I want to remove all special characters from a string except for digits and the degree symbol °. How can I do this using regex?

I know that .replaceAll("[^a-zA-Z0-9]+","") will remove all special characters, how do I put the degree symbol back in?

Answer 1

You may use \\W and use a character class subtraction :

.replaceAll("[\\W_&&[^°]]+","")

Another way is to add the degree symbol to the negated character class you have since the negated character class matches all chars other than those in the character class:

.replaceAll("[^a-zA-Z0-9°]+","")
                        ^

Tested at: http://www.ocpsoft.org/tutorials/regular-expressions/java-visual-regex-tester/ .

Answer 2

You can use unicode character: ° is \° . So your regex can look like this:

[^a-zA-Z0-9\\u00b0]+

Example: https://regex101.com/r/ZgGdHj/3