code: private void readNextChar(final JsonLevel level) throws EOFException {
          int readerIndex = content.readerIndex();
          int lastWsIndex = content.forEachByte(wsProcessor);
  
          if (lastWsIndex == -1 && level != null) {
              throw NEED_MORE_DATA;
          }
          if (lastWsIndex > readerIndex) {
              this.content.skipBytes(lastWsIndex - readerIndex);
              this.content.discardReadBytes();
          }
  
          this.currentChar = this.content.readByte();
      }
docs: Reads the next character into {@link #currentChar}.
  
  @param level the current level of nesting.
  @throws EOFException if more input is needed.