code: protected final boolean checkTTC(FontFileReader in, String name) throws IOException {
          String tag = in.readTTFString(4);
  
          if ("ttcf".equals(tag)) {
              // This is a TrueType Collection
              in.skip(4);
  
              // Read directory offsets
              int numDirectories = (int)in.readTTFULong();
              // int numDirectories=in.readTTFUShort();
              long[] dirOffsets = new long[numDirectories];
              for (int i = 0; i < numDirectories; i++) {
                  dirOffsets[i] = in.readTTFULong();
              }
  
              log.info("This is a TrueType collection file with "
                                     + numDirectories + " fonts");
              log.info("Containing the following fonts: ");
              // Read all the directories and name tables to check
              // If the font exists - this is a bit ugly, but...
              boolean found = false;
  
              // Iterate through all name tables even if font
              // Is found, just to show all the names
              long dirTabOffset = 0;
              for (int i = 0; (i < numDirectories); i++) {
                  in.seekSet(dirOffsets[i]);
                  readDirTabs(in);
  
                  readName(in);
  
                  if (fullName.equals(name)) {
                      found = true;
                      dirTabOffset = dirOffsets[i];
                      log.info(fullName + " <-- selected");
                  } else {
                      log.info(fullName);
                  }
  
                  // Reset names
                  notice = "";
                  fullName = "";
                  familyName = "";
                  fontName = "";
                  subFamilyName = "";
              }
  
              in.seekSet(dirTabOffset);
              return found;
          } else {
              in.seekSet(0);
              return true;
          }
      }
docs: Check if this is a TrueType collection and that the given
  name exists in the collection.
  If it does, set offset in fontfile to the beginning of
  the Table Directory for that font.
  @param in FontFileReader to read from
  @param name The name to check
  @return True if not collection or font name present, false otherwise
  @throws IOException In case of an I/O problem