A Groovy + Java solution for Project Euler - Problem 30

euler30.groovy

(1000..200000).inject 0, { sum, number ->
    numberMuncher = new NumberMuncher(number)
    digitsToFifthPower = numberMuncher.digitsToThePowerOf(5)
    sumOfDigitsToTheFifthPower = digitsToFifthPower.sum()
    
    sum += (number == sumOfDigitsToTheFifthPower) ? number : 0
}

NumberMuncher.java

class NumberMuncher {
    private final Integer value;
 
    NumberMuncher(Integer value) {
        this.value = value;
    }     
 
    List<Integer> digitsToThePowerOf(int power) {
        List<Integer> listOfPowers = new ArrayList<Integer>();
        List<Integer> digits = toDigits();
        for (Integer digit : digits) {
            Double powerOf = Math.pow(digit, power);
            listOfPowers.add(powerOf.intValue());
        }

        return listOfPowers;
    }

    List<Integer> toDigits() {
        List<Integer> listOfDigits = new ArrayList<Integer>();
        char[] characters = characterArrayOfValue();
        for (Character c : characters) {
            listOfDigits.add(Character.getNumericValue(c));
        }

        return listOfDigits;
    }
    
    char[] characterArrayOfValue() {
        String string = this.value.toString();
        
        return string.toCharArray();
    }    
}