Package org.apache.hadoop.fs.store

Class EtagChecksum

java.lang.Object

org.apache.hadoop.fs.FileChecksum

org.apache.hadoop.fs.store.EtagChecksum

All Implemented Interfaces:

Writable

public class EtagChecksum
extends FileChecksum

An etag as a checksum. Consider these suitable for checking if an object has changed, but not suitable for comparing two different objects for equivalence, especially between object stores.

Constructor Summary

Constructors

Constructor	Description
EtagChecksum()	Create with an empty etag.
EtagChecksum(java.lang.String eTag)	Create with a string etag.

Method Summary

Modifier and Type	Method	Description
java.lang.String	getAlgorithmName()	The checksum algorithm name.
byte[]	getBytes()	The value of the checksum in bytes.
int	getLength()	The length of the checksum in bytes.
void	readFields(java.io.DataInput in)	Deserialize the fields of this object from in.
java.lang.String	toString()
void	write(java.io.DataOutput out)	Serialize the fields of this object to out.

Methods inherited from class org.apache.hadoop.fs.FileChecksum

equals, getChecksumOpt, hashCode

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Constructor Detail

EtagChecksum

public EtagChecksum()

Create with an empty etag.

EtagChecksum

public EtagChecksum(java.lang.String eTag)

Create with a string etag.

Parameters:

eTag - etag

Method Detail

getAlgorithmName

public java.lang.String getAlgorithmName()

Description copied from class: FileChecksum

The checksum algorithm name.

Specified by:

getAlgorithmName in class FileChecksum

Returns:

algorithm name.

getLength

public int getLength()

Description copied from class: FileChecksum

The length of the checksum in bytes.

Specified by:

getLength in class FileChecksum

Returns:

length.

getBytes

public byte[] getBytes()

Description copied from class: FileChecksum

The value of the checksum in bytes.

Specified by:

getBytes in class FileChecksum

Returns:

byte array.

write

public void write(java.io.DataOutput out)
           throws java.io.IOException

Description copied from interface: Writable

Serialize the fields of this object to out.

Parameters:

out - DataOuput to serialize this object into.

Throws:

java.io.IOException - any other problem for write.

readFields

public void readFields(java.io.DataInput in)
                throws java.io.IOException

Description copied from interface: Writable

Deserialize the fields of this object from in.

For efficiency, implementations should attempt to re-use storage in the existing object where possible.

Parameters:

in - DataInput to deseriablize this object from.

Throws:

java.io.IOException - any other problem for readFields.

toString

public java.lang.String toString()

Overrides:

toString in class java.lang.Object