Regular Reads will block until data is available, but not wait for a full buffer. 
Writes will block until there is space available and writes bigger than the buffer will wait for reads to make space.

`TryRead` and `TryWrite` are still available for non-blocking reads and writes.

To signify the end of the stream, close the ring buffer from the writer side with `rb.CloseWriter()`

            if (item != null && item.isUpdated()) {
                try {
                    writer.write(item.toLineString());
                    writer.write(Constants.LINE_SEPARATOR);
                    return item;
                } catch (final IOException e) {
                    throw new DictionaryException("Failed to write: " + item, e);
                }
            }
            return null;
        }

                throw new DictionaryException("Failed to write: " + oldItem + " -> " + item, e);
            }
        }

        /**
         * Writes a string line to the temporary file.
         * @param line the line to write
         */
        public void write(final String line) {
            try {
                writer.write(line);
                writer.write(Constants.LINE_SEPARATOR);

                try {
                    writer.write(s);
                    writer.write('\n');
                } catch (final IOException e) {
                    throw new IORuntimeException(e);
                }
            });
        } catch (final Exception e) {
            logger.warn("Failed to write thread dump: file={}", file, e);
        }
    }

    /**

                throw new DictionaryException("Failed to write: " + oldItem + " -> " + item, e);
            }
        }

        /**
         * Writes a line to the new file.
         *
         * @param line The line to write.
         */
        public void write(final String line) {
            try {
                writer.write(line);
                writer.write(Constants.LINE_SEPARATOR);

      }
      if (associatedStreamId == 0) {
        writer.headers(outFinished, streamId, requestHeaders)
      } else {
        require(!client) { "client streams shouldn't have associated stream IDs" }
        // HTTP/2 has a PUSH_PROMISE frame.
        writer.pushPromise(associatedStreamId, streamId, requestHeaders)
      }
    }

    if (flushHeaders) {
      writer.flush()
    }

    return stream
  }

Joe Tsai <******@****.***> 1503528984 -0700

   * writer will close the target if it is {@link Closeable}, and flushing the writer will flush the
   * target if it is {@link java.io.Flushable}.
   *
   * @param target the object to which output will be sent
   * @return a new Writer object, unless target is a Writer, in which case the target is returned
   */
  public static Writer asWriter(Appendable target) {
    if (target instanceof Writer) {
      return (Writer) target;
    }

  fun fromDer(byteString: ByteString): T {
    val buffer = Buffer().write(byteString)
    val reader = DerReader(buffer)
    return fromDer(reader)
  }

  /**
   * Writes [value] to this adapter, unless it is the default value and can be safely omitted.
   *
   * If this does write a value, it will write a tag and a length and a full value.
   */
  fun toDer(
    writer: DerWriter,
    value: T,
  )

    }

    return result
  }

  override fun toDer(
    writer: DerWriter,
    value: T,
  ) {
    if (typeHint) {
      writer.typeHint = value
    }

    if (isOptional && value == defaultValue) {
      // Nothing to write!
      return
    }

    writer.write(name, tagClass, tag) {
      codec.encode(writer, value)
    }
  }

  /**