Java Number to byte array without using String

NumberConverter.java

    public static char[] numberToByteArray(int number) {
        int numDigits = getNumDigits(number);
        char[] charArray = new char[numDigits];
        for (int i = numDigits - 1; i >= 0; i--) {
            charArray[i] = (char)('0' + number % 10);
            number /= 10;
        }
        return charArray;
    }

    // Method to convert a double to a char array
    public static char[] numberToByteArray(double number) {
        // Convert the integer part
        int intValue = (int) number;
        char[] intPart = numberToByteArray(intValue);

        // Convert the fractional part
        number -= intValue;
        StringBuilder decimalPartBuilder = new StringBuilder();
        decimalPartBuilder.append('.');
        int numDecimals = 0;
        while (number > 0 && numDecimals < 6) {
            number *= 10;
            int digit = (int) number;
            decimalPartBuilder.append((char)('0' + digit));
            number -= digit;
            numDecimals++;
        }

        // Remove trailing zeros
        while (decimalPartBuilder.length() > 1 && decimalPartBuilder.charAt(decimalPartBuilder.length() - 1) == '0') {
            decimalPartBuilder.deleteCharAt(decimalPartBuilder.length() - 1);
        }

        // Concatenate the integer and decimal parts
        String decimalPartString = decimalPartBuilder.toString();
        char[] result = new char[intPart.length + decimalPartString.length()];
        System.arraycopy(intPart, 0, result, 0, intPart.length);
        decimalPartString.getChars(0, decimalPartString.length(), result, intPart.length);
        return result;
    }

    // Method to calculate the number of digits in an integer
    private static int getNumDigits(int number) {
        if (number == 0) return 1;
        int count = 0;
        while (number != 0) {
            number /= 10;
            count++;
        }
        return count;
    }