code: @Override
      public long read(ByteBuffer[] dsts, int offset, int length) throws IOException
      {
          long rc = fillAppRead();
          if (rc <= 0)
          {
              return rc;
          }
          return ByteBuffers.move(appRead, dsts, offset, length);
      }
docs: Reads ByteBuffer from peer. Starts handshaking if needed.
  @param dsts
  @param offset
  @param length
  @return
  @throws IOException
  @throws HelloForwardException if client hello triggers host filter.
  @see org.vesalainen.net.ssl.AbstractSSLSocketChannel#setHostFilter(java.util.function.Predicate)