alluxio.master.file.meta.xattr

Interface ExtendedAttribute<T>

Type Parameters:

T - The type of object to encode/decode

All Known Implementing Classes:

AbstractExtendedAttribute

public interface ExtendedAttribute<T>

This class defines an interface for implementing an extended attribute which can be stored on inodes. Attributes are stored on inodes as a simple array of byte and define their implementations for encoding/decoding

Nested Class Summary

Nested Classes

Modifier and Type	Interface and Description
static class	ExtendedAttribute.NamespacePrefix The namespace for extended attributes.

Method Summary

Modifier and Type	Method and Description
T	decode(byte[] bytes) Decode an object from a single byte string.
byte[]	encode(T object) Encode a single object into a byte string.
String	getIdentifier()
String	getName()
String	getNamespace()

Method Detail

getName

String getName()

Returns:

the full attribute with namespace and identifier

getNamespace

String getNamespace()

Returns:

the namespace of the attribute lies within

getIdentifier

String getIdentifier()

Returns:

the identifier within the namespace of the attribute

encode

byte[] encode(T object)

Encode a single object into a byte string.

Parameters:

object - the object to encode

Returns:

the byte representation of the object

decode

T decode(byte[] bytes)
  throws IOException

Decode an object from a single byte string.

Parameters:

bytes - the bytes to decode into a single instance of

Returns:

the instance of the decoded object

Throws:

IOException - if the size of the byte string isn't equal to the encoding length