|
||||||||||
PREV CLASS NEXT CLASS | FRAMES NO FRAMES | |||||||||
SUMMARY: NESTED | FIELD | CONSTR | METHOD | DETAIL: FIELD | CONSTR | METHOD |
java.lang.Objectorg.apache.hadoop.hdfs.server.protocol.ServerCommand
org.apache.hadoop.hdfs.server.protocol.NamenodeCommand
org.apache.hadoop.hdfs.server.protocol.CheckpointCommand
@InterfaceAudience.Private @InterfaceStability.Evolving public class CheckpointCommand
Checkpoint command.
Returned to the backup node by the name-node as a reply to the
NamenodeProtocol.startCheckpoint(NamenodeRegistration)
request.
Contains:
CheckpointSignature
identifying the particular checkpoint
Constructor Summary | |
---|---|
CheckpointCommand()
|
|
CheckpointCommand(CheckpointSignature sig,
boolean isImgObsolete,
boolean needToReturnImg)
|
Method Summary | |
---|---|
CheckpointSignature |
getSignature()
Checkpoint signature is used to ensure that nodes are talking about the same checkpoint. |
boolean |
isImageObsolete()
Indicates whether current backup image is obsolete, and therefore need to be discarded? |
boolean |
needToReturnImage()
Indicates whether the new checkpoint image needs to be transfered back to the name-node after the checkpoint is done. |
void |
readFields(DataInput in)
|
void |
write(DataOutput out)
|
Methods inherited from class org.apache.hadoop.hdfs.server.protocol.ServerCommand |
---|
getAction |
Methods inherited from class java.lang.Object |
---|
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait |
Constructor Detail |
---|
public CheckpointCommand()
public CheckpointCommand(CheckpointSignature sig, boolean isImgObsolete, boolean needToReturnImg)
Method Detail |
---|
public CheckpointSignature getSignature()
public boolean isImageObsolete()
public boolean needToReturnImage()
public void write(DataOutput out) throws IOException
write
in interface org.apache.hadoop.io.Writable
write
in class ServerCommand
IOException
public void readFields(DataInput in) throws IOException
readFields
in interface org.apache.hadoop.io.Writable
readFields
in class ServerCommand
IOException
|
||||||||||
PREV CLASS NEXT CLASS | FRAMES NO FRAMES | |||||||||
SUMMARY: NESTED | FIELD | CONSTR | METHOD | DETAIL: FIELD | CONSTR | METHOD |