private byte nextTC() throws IOException {
  if (hasPushbackTC) {
    hasPushbackTC=false;
  }
 else {
    pushbackTC=input.readByte();
  }
  return pushbackTC;
}

private byte nextTC ( ) throws IOException { if ( hasPushbackTC ) { hasPushbackTC = false ; } else { pushbackTC = input . readByte ( ) ; } return pushbackTC ; }
return the next token code ( tc ) from the receiver , which indicates what kind of object follows
