Roman Numerals help

I have to convert Roman Numerals to a Decimal Number, I got how to do it, but don't know to restrict somethings,

There is a rule that one symbol cannot repeat more than three times at once, so XIIII should not work, instead it should be XIV, but I do not know how to do this.

I put an if statement within the for loop in class Translate, method numeral, but it does not work.

Code:

---

import java.io.*;
import java.util.*;


public class RomanNumeral
{
  public static void main (String[] args) throws IOException
  { 
    BufferedReader objReader = new BufferedReader (new InputStreamReader (System.in));
   
   
    for (;;)
    {
      System.out.println();
      System.out.println("Enter roman numeral numbers:");
      String romanNumeral = objReader.readLine();
     
      Translate arabNumeral = new Translate(romanNumeral);
     
      String finalOut = arabNumeral.getNumeral();
     
      System.out.println("The conversion is:");
      System.out.println(finalOut); 
    }
   
   
  }
}

class Translate
{
  private String word, roman, result;
  private int length, addition = 0;
 
 
  Translate(String roman)
  {
    this.roman = roman;
    numeral();
  }
 
  public void numeral()
  {
    Scanner conversion = new Scanner(roman);
    StringBuffer combine = new StringBuffer ("");
   
   
    while (conversion.hasNext())
    {
      word = conversion.next();
      length = word.length();
     
     
      for (int i = 0; i < length-1;i++)
      {
          if (word.charAt(i) == 'I' && (word.charAt(i+1) == 'V' || word.charAt(i+1) == 'X' || word.charAt(i+1) == 'L' || word.charAt(i+1) == 'C' || word.charAt(i+1) == 'D' || word.charAt(i+1) == 'M'))
          {
            addition--;
          }
          else if (word.charAt(i) == 'I' && word.charAt(i+1) == 'I')
          {
            addition++;
          }
          else if (word.charAt(i) == 'V' && (word.charAt(i+1) == 'X' || word.charAt(i+1) == 'L' || word.charAt(i+1) == 'C' || word.charAt(i+1) == 'D' || word.charAt(i+1) == 'M'))
          {
            addition -= 5;
          }
          else if (word.charAt(i) == 'V' && (word.charAt(i+1) == 'I' || word.charAt(i+1) == 'V'))
          {
            addition += 5;
          }
          else if (word.charAt(i) == 'X' && (word.charAt(i+1) == 'L' || word.charAt(i+1) == 'C' || word.charAt(i+1) == 'D' || word.charAt(i+1) == 'M'))
          {
            addition -= 10;
          }
          else if (word.charAt(i) == 'X' && (word.charAt(i+1) == 'I' || word.charAt(i+1) == 'V' || word.charAt(i+1) == 'X'))
          {
            addition += 10;
          }
          else if (word.charAt(i) == 'L' && (word.charAt(i+1) == 'C' || word.charAt(i+1) == 'D' || word.charAt(i+1) == 'M'))
          {
            addition -= 50;
          }
          else if (word.charAt(i) == 'L' && (word.charAt(i+1) == 'I' || word.charAt(i+1) == 'V' || word.charAt(i+1) == 'X' || word.charAt(i+1) == 'L'))
          {
            addition += 50;
          }
          else if (word.charAt(i) == 'C' && (word.charAt(i+1) == 'D' || word.charAt(i+1) == 'M'))
          {
            addition -= 100;
          }
          else if (word.charAt(i) == 'C' && (word.charAt(i+1) == 'I' || word.charAt(i+1) == 'V' || word.charAt(i+1) == 'X' || word.charAt(i+1) == 'L' || word.charAt(i+1) == 'C'))
          {
            addition += 100;
          }
          else if (word.charAt(i) == 'D' && (word.charAt(i+1) == 'M'))
          {
            addition -= 500;
          }
          else if (word.charAt(i) == 'D' && (word.charAt(i+1) == 'I' || word.charAt(i+1) == 'V' || word.charAt(i+1) == 'X' || word.charAt(i+1) == 'L' || word.charAt(i+1) == 'C' || word.charAt(i+1) == 'D'))
          {
            addition += 500;
          }
          else if (word.charAt(i) == 'M' && (word.charAt(i+1) == 'I' || word.charAt(i+1) == 'V' || word.charAt(i+1) == 'X' || word.charAt(i+1) == 'L' || word.charAt(i+1) == 'C' || word.charAt(i+1) == 'D' || word.charAt(i+1) == 'M'))
          {
            addition += 1000;
          }
      }
      if (word.charAt(length-1) == 'I')
      {
        addition++;
      }
      else if (word.charAt(length-1) == 'V')
      {
        addition += 5;
      }
      else if (word.charAt(length-1) == 'X')
      {
        addition += 10;
      }
      else if (word.charAt(length-1) == 'L')
      {
        addition += 50;
      }
      else if (word.charAt(length-1) == 'C')
      {
        addition += 100;
      }
      else if (word.charAt(length-1) == 'D')
      {
        addition += 500;
      }
      else if (word.charAt(length-1) == 'M')
      {
        addition += 1000;
      }
     
      combine.append(addition);
      combine.append(' ');
     
      addition = 0;
    }
    result = combine.toString ();
  }
 
  public String getNumeral()
  {
    return result;
  } 
}

---

Java Programming: Solution to Programming Exercise

Thanks