What about:
- Peter Müller
- François Hollande
- Patrick O’Brian
- Silvana Koch-Mehrin
Validating names is a difficult issue, because valid names are not only consisting of the letters A-Z.
At least you should use the Unicode property for letters and add more special characters. A first approach could be e.g.:
String regx = "^[\\p{L} .'-]+$";
\\p{L}
is a Unicode Character Property that matches any kind of letter from any language