Test if internal buffer is empty
Get what was collected in internal buffer and clear it.
Append data processor to pipeline
Process next data portion. Data passed over pipeline and result stored in buffer.
Process next data portion. Data passed over pipeline and store result in buffer.
DataPipe is a pipeline of data processors, each accept some data, process it, and put result to next element in line. This class used to combine different Transfer- and Content- encodings. For example: unchunk transfer-encoding "chunnked", and uncompress Content-Encoding "gzip".