public class Exercise7_9 {    public static void main(String[] args) {        System.out.println(convertDecimalToHex(16));        System.out.println(convertDecimalToHex(298));        System.out.println(convertDecimalToHex(9123));    }        public static String convertDecimalToHex(int value) {        StringBuffer buffer = new StringBuffer();                while (value != 0) {            int number = value % 16;            char ch = convertToHex(number);            buffer.insert(0, ch);            value = value / 16;        }                return buffer.toString();    }         public static char convertToHex(int number) {         if (number == 10)              return 'A';         else if (number == 11)              return 'B';         else if (number == 12)              return 'C';         else if (number == 13)              return 'D';         else if (number == 14)              return 'E';         else if (number == 15)              return 'F';         return (char)(number + '0');     }}