Roman Numeral Complete

import java.util.Map;
import java.util.SortedMap;
import java.util.TreeMap;

/**
 * @author deliveryninja
 *
 * Given a numeral from 1 to 3000 this will return the Roman
 * numberal equivalent.
 *
 * @param numeral
 * @return
 */
public class Roman {

    public enum RomanNumeral{
        M(1000),
        CM(900),
        D(500),
        CD(400),
        C(100),
        XC(90),
        L(50),
        XL(40),
        X(10),
        IX(9),
        V(5),
        IV(4),
        I(1);

        private int value;

        RomanNumeral(int value){
            this.value = value;
        }

        public int getIntegerValue() {
            return value;
        }
    }

    public String romanize(int numeral) {
        StringBuffer result = new StringBuffer();
        for(RomanNumeral romanNumeral : RomanNumeral.values()){
            while(numeral >= romanNumeral.getIntegerValue()){
                result.append(romanNumeral);
                numeral -= romanNumeral.getIntegerValue();
            }
        }
        return result.toString();
    }

    public int convertToNumeral(String input) {
        int result = 0;

        //Loop left to right across the input number
        for(int index = 0; index < input.length() ; index++){
            //Check the current value with all known roman values
            for(RomanNumeral romanNumeral : RomanNumeral.values()){
                //Check if the next value is 1 or 2 characters long
                int adjustedIndex = calculateIndexPosition(romanNumeral, index+1, input.length());
                //Compare the input and current roman numeral
                if(input.substring(index, adjustedIndex).equals(romanNumeral.toString())){
                    result += romanNumeral.getIntegerValue(); //Increment the result
                    //Increment the index so we don't re-evaluate the same characters
                    index = adjustedIndex - 1;
                }
            }
        }
        return result;
    }

    private int calculateIndexPosition(RomanNumeral romanNumeral, int index, int inputLength){
        //Check if the length is larger than 1 and there is more than 1 character in the input
        if(romanNumeral.toString().length() > 1 && index < inputLength){
                index++; //Increment index to check 2 characters
        }
        return index;
    }
}