org.apache.hadoop.hdfs.server.protocol
Class UpgradeCommand
java.lang.Object
org.apache.hadoop.hdfs.server.protocol.ServerCommand
org.apache.hadoop.hdfs.server.protocol.DatanodeCommand
org.apache.hadoop.hdfs.server.protocol.UpgradeCommand
- All Implemented Interfaces:
- org.apache.hadoop.io.Writable
@InterfaceAudience.Private
@InterfaceStability.Evolving
public class UpgradeCommand
- extends DatanodeCommand
This as a generic distributed upgrade command.
During the upgrade cluster components send upgrade commands to each other
in order to obtain or share information with them.
It is supposed that each upgrade defines specific upgrade command by
deriving them from this class.
The upgrade command contains version of the upgrade, which is verified
on the receiving side and current status of the upgrade.
Methods inherited from class java.lang.Object |
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait |
UC_ACTION_REPORT_STATUS
public static final int UC_ACTION_REPORT_STATUS
- See Also:
- Constant Field Values
UC_ACTION_START_UPGRADE
public static final int UC_ACTION_START_UPGRADE
- See Also:
- Constant Field Values
UpgradeCommand
public UpgradeCommand()
UpgradeCommand
public UpgradeCommand(int action,
int version,
short status)
getVersion
public int getVersion()
getCurrentStatus
public short getCurrentStatus()
write
public void write(DataOutput out)
throws IOException
- Specified by:
write
in interface org.apache.hadoop.io.Writable
- Overrides:
write
in class ServerCommand
- Throws:
IOException
readFields
public void readFields(DataInput in)
throws IOException
- Specified by:
readFields
in interface org.apache.hadoop.io.Writable
- Overrides:
readFields
in class ServerCommand
- Throws:
IOException
Copyright © 2009 The Apache Software Foundation