package pr2.lambda.mogrifier_2;

@FunctionalInterface  
public interface StringFunction {
    static StringFunction caesar(final int shift) {
        return (s) -> shiftCharacters(s, shift);
    }

    static String shiftCharacters(String s, int shift) {
        char[] c = s.toCharArray();
        for (int i = 0; i < c.length; i++) {
            c[i] = (char) (c[i] + shift);
        }
        return new String(c);
    }

    String apply(String s);
}