Question

How do you check if a one-character String is a letter – including any letters with accents?

I had to work this out recently, so I’ll answer it myself, after the recent VB6 question reminded me.

Answer 1

Just checking if a letter is in A-Z because that doesn’t include letters with accents or letters in other alphabets.

I found out that you can use the regular expression class for ‘Unicode letter’, or one of its case-sensitive variations:

string.matches('\\p{L}'); // Unicode letter string.matches('\\p{Lu}'); // Unicode upper-case letter 

You can also do this with Character class:

Character.isLetter(character); 

but that is less convenient if you need to check more than one letter.