Quick 'n tidy Hex Dump method

example_output.txt

  - 0000 0000 0000 0000 0000 0000 0000 0000 ................
  - 6425 a19c 0001 0003 0000 0000 5554 0500 d%??........UT..
  - 011c 2f38 53                            ../8S           

hex.java

    private static String doHex(byte[] data, int offset, int length) {
        StringBuilder sb = new StringBuilder();
        int end = offset+length;
        while(offset < end) {
            sb.append("  - ");

            for(int i=0; i<16; i++) {
                if( i+offset >= data.length) {
                    sb.append("  ");
                }
                else {
                    if ((data[i+offset] & 0x0ff) < 16) sb.append("0");
                    sb.append(Integer.toHexString(data[i + offset] & 0x0FF));
                }
                if( (i & 0x01) == 0x01 ) sb.append(" ");
            }

            for(int i=0; i<16; i++) {
                if( i+offset >= data.length) {
                    sb.append(" ");
                }
                else if( (data[i+offset] & 0x0ff) < 32 ) {
                    sb.append(".");
                }
                else if( (data[i+offset] & 0x0ff) >= 127 ) {
                    sb.append("?");
                }
                else {
                    sb.append((char)data[i+offset]);
                }
            }

            sb.append("\n");
            offset += 16;
        }
        return sb.toString();
    }