public static String hexDump()

in ch-commons-util/src/main/java/com/cloudhopper/commons/util/StringUtil.java [585:657]
44 lines of code
11 McCabe index (conditional complexity)

    public static String hexDump(String prefix, byte[] data) {
        byte byte_value;

        StringBuffer str = new StringBuffer(data.length * 3);

        str.append(prefix);

        for (int i = 0; i < data.length; i += 16) {
            // dump the header: 00000000:
            String offset = Integer.toHexString(i);

            // "0" left pad offset field so it is always 8 char's long.
            str.append("  ");
            for (int offlen = offset.length(); offlen < 8; offlen++) {
                str.append("0");
            }
            str.append(offset);
            str.append(":");

            // dump hex version of 16 bytes per line.
            for (int j = 0; (j < 16) && ((i + j) < data.length); j++) {
                byte_value = data[i + j];

                // add spaces between every 2 bytes.
                if ((j % 2) == 0) {
                    str.append(" ");
                }

                // dump a single byte.
                byte high_nibble = (byte) ((byte_value & 0xf0) >>> 4);
                byte low_nibble = (byte) (byte_value & 0x0f);

                str.append(HEX_TABLE[high_nibble]);
                str.append(HEX_TABLE[low_nibble]);
            }

            // IF THIS IS THE LAST LINE OF HEX, THEN ADD THIS
            if (i + 16 > data.length) {
                // for debugging purposes, I want the last bytes always padded
                // over so that the ascii portion is correctly positioned
                int last_row_byte_count = data.length % 16;
                int num_bytes_short = 16 - last_row_byte_count;
                // number of spaces to add = (num bytes remaining * 2 spaces per byte) + (7 - (num bytes % 2))
                int num_spaces = (num_bytes_short * 2) + (7 - (last_row_byte_count / 2));
                for (int v = 0; v < num_spaces; v++) {
                    str.append(" ");
                }
            }

            // dump ascii version of 16 bytes
            str.append("  ");

            for (int j = 0; (j < 16) && ((i + j) < data.length); j++) {
                char char_value = (char) data[i + j];

                // RESOLVE (really want isAscii() or isPrintable())
                //if (Character.isLetterOrDigit(char_value))
                if (isPrintableChar(char_value)) {
                    str.append(String.valueOf(char_value));
                } else {
                    str.append(".");
                }
            }

            // new line
            str.append("\n");
        }

        // always trim off the last newline
        str.deleteCharAt(str.length() - 1);

        return (str.toString());
    }