org.apache.hadoop.hbase.io.hfile.bucket

Interface IOEngine

All Known Implementing Classes:

ByteBufferIOEngine, FileIOEngine

@InterfaceAudience.Private
public interface IOEngine

A class implementing IOEngine interface could support data services for BucketCache.

Method Summary

Methods

Modifier and Type	Method and Description
boolean	isPersistent()
int	read(ByteBuffer dstBuffer, long offset) Transfers data from IOEngine to the given byte buffer
void	shutdown() Shutdown the IOEngine
void	sync() Sync the data to IOEngine after writing
void	write(ByteBuffer srcBuffer, long offset) Transfers data from the given byte buffer to IOEngine

Method Detail

isPersistent

boolean isPersistent()

Returns:

true if persistent storage is supported for the cache when shutdown

read

int read(ByteBuffer dstBuffer,
       long offset)
         throws IOException

Transfers data from IOEngine to the given byte buffer

Parameters:

dstBuffer - the given byte buffer into which bytes are to be written

offset - The offset in the IO engine where the first byte to be read

Returns:

number of bytes read

Throws:

IOException

write

void write(ByteBuffer srcBuffer,
         long offset)
           throws IOException

Transfers data from the given byte buffer to IOEngine

Parameters:

srcBuffer - the given byte buffer from which bytes are to be read

offset - The offset in the IO engine where the first byte to be written

Throws:

IOException

sync

void sync()
          throws IOException

Sync the data to IOEngine after writing

Throws:

IOException

shutdown

void shutdown()

Shutdown the IOEngine