private static Double readRealNumber()

in fontbox/src/main/java/org/apache/fontbox/cff/CFFParser.java [441:526]
82 lines of code
24 McCabe index (conditional complexity)

    private static Double readRealNumber(DataInput input) throws IOException
    {
        StringBuilder sb = new StringBuilder();
        boolean done = false;
        boolean exponentMissing = false;
        boolean hasExponent = false;
        int[] nibbles = new int[2];
        while (!done)
        {
            int b = input.readUnsignedByte();
            nibbles[0] = b / 16;
            nibbles[1] = b % 16;
            for (int nibble : nibbles)
            {
                switch (nibble)
                {
                case 0x0:
                case 0x1:
                case 0x2:
                case 0x3:
                case 0x4:
                case 0x5:
                case 0x6:
                case 0x7:
                case 0x8:
                case 0x9:
                    sb.append(nibble);
                    exponentMissing = false;
                    break;
                case 0xa:
                    sb.append('.');
                    break;
                case 0xb:
                    if (hasExponent)
                    {
                        LOG.warn("duplicate 'E' ignored after {}", sb);
                        break;
                    }
                    sb.append('E');
                    exponentMissing = true;
                    hasExponent = true;
                    break;
                case 0xc:
                    if (hasExponent)
                    {
                        LOG.warn("duplicate 'E-' ignored after {}", sb);
                        break;
                    }
                    sb.append("E-");
                    exponentMissing = true;
                    hasExponent = true;
                    break;
                case 0xd:
                    break;
                case 0xe:
                    sb.append('-');
                    break;
                case 0xf:
                    done = true;
                    break;
                default:
                    // can only be a programming error because a nibble is between 0 and F 
                    throw new IllegalArgumentException("illegal nibble " + nibble);
                }
            }
        }
        if (exponentMissing)
        {
            // the exponent is missing, just append "0" to avoid an exception
            // not sure if 0 is the correct value, but it seems to fit
            // see PDFBOX-1522
            sb.append('0');
        }
        if (sb.length() == 0)
        {
            return 0d;
        }
        try
        {
            return Double.valueOf(sb.toString());
        }
        catch (NumberFormatException ex)
        {
            throw new IOException(ex);
        }
    }