String s1 ="Turtle123456_fly.me";
String s2 ="birdy_12345678_prd.tr";
Pattern p = Pattern.compile("^([A-Za-z]+)[^A-Za-z]");
Matcher matcher = p.matcher(s1);
if (matcher.find()) {
System.out.println(matcher.group(1));
}
:
^([A-Za-z]+) - , , ( ^).
[^A-Za-z] - .
, , - 1 ( 1 - , ).