string - How to trim no-break space in Java?

Question

I've input an input file which I need to process and discard all the white-spaces, including non-breaking space U+00A0 aka   (You can produce it in Notepad by pressing Alt and then typing 0 1 6 0 from the keyboard's numeric pad.) or any other form of white space. I have tried String.trim() but it doesn't trim U+00A0.

Do I need to explicitly check for U+00A0 and then trim() or is there an easy way to trim all kinds of white-spaces in Java?

Answer 1

While   is a non breaking space (a space that does not want to be treated as whitespace), you can trim a string while preserving every   within the string with a simple regex:

string.replaceAll("(^\h*)|(\h*$)","")

• h is a horizontal whitespace character: [ xA0u1680u180eu2000-u200au202fu205fu3000]

If you are using a pre JDK8 Version, you need to explicitly use the list of chars instead of h.