org.apache.hadoop.hdfs.server.protocol

类 UpgradeCommand

java.lang.Object

org.apache.hadoop.hdfs.server.protocol.DatanodeCommand

org.apache.hadoop.hdfs.server.protocol.UpgradeCommand

所有已实现的接口:

Writable

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.

字段概要

字段

限定符和类型	字段和说明
static int	UC_ACTION_REPORT_STATUS
static int	UC_ACTION_START_UPGRADE

从类继承的字段 org.apache.hadoop.hdfs.server.protocol.DatanodeCommand

FINALIZE, REGISTER

构造器概要

构造器

构造器和说明
UpgradeCommand()
UpgradeCommand(int action, int version, short status)

方法概要

方法

限定符和类型	方法和说明
short	getCurrentStatus()
int	getVersion()
void	readFields(DataInput in) Deserialize the fields of this object from in.
void	write(DataOutput out) Serialize the fields of this object to out.

从类继承的方法 org.apache.hadoop.hdfs.server.protocol.DatanodeCommand

getAction

从类继承的方法 java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

字段详细资料

UC_ACTION_REPORT_STATUS

public static final int UC_ACTION_REPORT_STATUS

另请参阅:

常量字段值

UC_ACTION_START_UPGRADE

public static final int UC_ACTION_START_UPGRADE

另请参阅:

常量字段值

构造器详细资料

UpgradeCommand

public UpgradeCommand()

UpgradeCommand

public UpgradeCommand(int action,
              int version,
              short status)

方法详细资料

getVersion

public int getVersion()

getCurrentStatus

public short getCurrentStatus()

write

public void write(DataOutput out)
           throws IOException

从接口复制的说明: Writable

Serialize the fields of this object to out.

指定者:

write 在接口中 Writable

覆盖:

write 在类中 DatanodeCommand

参数:

out - DataOuput to serialize this object into.

抛出:

IOException

readFields

public void readFields(DataInput in)
                throws IOException

从接口复制的说明: Writable

Deserialize the fields of this object from in.

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

指定者:

readFields 在接口中 Writable

覆盖:

readFields 在类中 DatanodeCommand

参数:

in - DataInput to deseriablize this object from.

抛出:

IOException