org.apache.hadoop.hdfs.server.datanode.fsdataset

Interface FsVolumeReference

All Superinterfaces:

AutoCloseable, Closeable

public interface FsVolumeReference
extends Closeable

This holds volume reference count as AutoClosable resource. It increases the reference count by one in the constructor, and decreases the reference count by one in close().

  try (FsVolumeReference ref = volume.obtainReference()) {
      // Do IOs on the volume
      volume.createRwb(...);
      ...
    }
  
 

Method Summary

Methods

Modifier and Type	Method and Description
void	close() Decrease the reference count of the volume.
FsVolumeSpi	getVolume() Returns the underlying volume object.

Method Detail

close

void close()
           throws IOException

Decrease the reference count of the volume.

Specified by:

close in interface AutoCloseable

Specified by:

close in interface Closeable

Throws:

IOException - it never throws IOException.

getVolume

FsVolumeSpi getVolume()

Returns the underlying volume object. Return null if the reference was released.