/**
 * A class that uses recursion to format a number in any base/radix
 * (in the interval [2, 6])
 *
 * @author  Prof. David Bernstein, James Madison Unversity
 * @verions 1.0
 */
 public class RadixFormatter
 {
    private final int    MAX_BASE    = 36;
    private final char[] DIGIT_TABLE = 
	 				{
					'0','1','2','3','4','5','6','7','8',
					'9','A','B','C','D','E','F','G','H',
					'I','J','K','L','M','N','O','P','Q',
					'R','S','T','U','V','W','X','Y','Z'
                };

    /**
     * The "exposed" interface.  This function does
     * initialization and error-checking.
     *
     * @param n    The number to print
     * @param base The base to use
     * @return     The formatted String
     */
      public String formatInBase(int n, int base)
      {
			String         returnString;
	
			returnString = "";
			if ((base <= 1) || (base > MAX_BASE)) 
			{
	    		returnString = "Invalid base: "+base;
			} 
			else 
			{
	    		if (n < 0) 
	    		{
					returnString = "-";
					n = -n;
	    		}

	    		returnString += formatRecursively(n, base);
			} // end else

			return returnString;
    } // end formatInBase


    /**
     * The recursive function
     *
     * @param n    The number to print
     * @param base The base to use
     */
    	private String formatRecursively(int n, int base)
    	{
			String   returnString;

			returnString = "";
			if (n >= base) 
         {
	    		returnString = formatRecursively(n/base, base);
			}

			returnString += DIGIT_TABLE[n % base];

			return returnString;
    } // end formatRecursively
    
} // end RadixFormatterV1.java