[HBASE-5521] Move compression/decompression to an encoder specific encoding context

• Type: Improvement
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 0.95.0
• Hadoop Flags: Reviewed
• Assignee: He Yongqiang
• Reporter: He Yongqiang
• Created: 05/Mar/12 19:01
• Updated: 23/Sep/13 18:31
• Resolved: 19/Mar/12 20:12

Description

As part of working on HBASE-5313, we want to add a new columnar encoder/decoder. It makes sense to move compression to be part of encoder/decoder:
1) a scanner for a columnar encoded block can do lazy decompression to a specific part of a key value object
2) avoid an extra bytes copy from encoder to hblock-writer.

If there is no encoder specified for a writer, the HBlock.Writer will use a default compression-context to do something very similar to today's code.