You can use Character.isLetter(char c)
in Character class like this
String s = "Word#$#$% Word 1234";
StringBuffer r = new StringBuffer();
for (int k = 0; k < s.length(); k++) {
if(Character.isLetter(s.charAt(k)))
r.append(s.charAt(k));
}
System.out.println("Result " + r.toString());