code: HashMap readFormat6() throws IOException {
          HashMap h = new HashMap();
          rf.skipBytes(4);
          int start_code = rf.readUnsignedShort();
          int code_count = rf.readUnsignedShort();
          for (int k = 0; k < code_count; ++k) {
              int r[] = new int[2];
              r[0] = rf.readUnsignedShort();
              r[1] = getGlyphWidth(r[0]);
              h.put(Integer.valueOf(k + start_code), r);
          }
          return h;
      }
docs: The information in the maps of the table 'cmap' is coded in several formats.
  Format 6 is a trimmed table mapping. It is similar to format 0 but can have
  less than 256 entries.
  @return a <CODE>HashMap</CODE> representing this map
  @throws IOException the font file could not be read