public LetterValidator(@NonNull final CharSequence errorMessage,@NonNull final Case caseSensitivity,final boolean allowSpaces,@NonNull final char... allowedCharacters){
  super(errorMessage);
  setCaseSensitivity(caseSensitivity);
  allowSpaces(allowSpaces);
  setAllowedCharacters(allowedCharacters);
}

public LetterValidator ( @ NonNull final CharSequence errorMessage , @ NonNull final Case caseSensitivity , final boolean allowSpaces , @ NonNull final char ... allowedCharacters ) { super ( errorMessage ) ; setCaseSensitivity ( caseSensitivity ) ; allowSpaces ( allowSpaces ) ; setAllowedCharacters ( allowedCharacters ) ; }
creates a new validator , which allows to validate texts to ensure , that they only contain letters .
