Package org.apache.hadoop.hdfs.protocol.datatransfer

Class ReplaceDatanodeOnFailure

java.lang.Object

org.apache.hadoop.hdfs.protocol.datatransfer.ReplaceDatanodeOnFailure

@Private
@Evolving
public class ReplaceDatanodeOnFailure
extends Object

The setting of replace-datanode-on-failure feature.

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static enum	ReplaceDatanodeOnFailure.Policy	The replacement policies

Constructor Summary

Constructors

Constructor	Description
ReplaceDatanodeOnFailure(ReplaceDatanodeOnFailure.Policy policy, boolean bestEffort)

Method Summary

Modifier and Type	Method	Description
void	checkEnabled()	Check if the feature is enabled.
static ReplaceDatanodeOnFailure	get(org.apache.hadoop.conf.Configuration conf)	Get the setting from configuration.
boolean	isBestEffort()	Best effort means that the client will try to replace the failed datanode (provided that the policy is satisfied), however, it will continue the write operation in case that the datanode replacement also fails.
boolean	satisfy(short replication, DatanodeInfo[] existings, boolean isAppend, boolean isHflushed)	Does it need a replacement according to the policy?
String	toString()
static void	write(ReplaceDatanodeOnFailure.Policy policy, boolean bestEffort, org.apache.hadoop.conf.Configuration conf)	Write the setting to configuration.

Methods inherited from class java.lang.Object

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

Constructor Details

ReplaceDatanodeOnFailure

public ReplaceDatanodeOnFailure(ReplaceDatanodeOnFailure.Policy policy,
 boolean bestEffort)

Method Details

checkEnabled

public void checkEnabled()

Check if the feature is enabled.

isBestEffort

public boolean isBestEffort()

Best effort means that the client will try to replace the failed datanode (provided that the policy is satisfied), however, it will continue the write operation in case that the datanode replacement also fails.

Returns:

Suppose the datanode replacement fails. false: An exception should be thrown so that the write will fail. true : The write should be resumed with the remaining datandoes.

satisfy

public boolean satisfy(short replication,
 DatanodeInfo[] existings,
 boolean isAppend,
 boolean isHflushed)

Does it need a replacement according to the policy?

toString

public String toString()

Overrides:

toString in class Object

get

public static ReplaceDatanodeOnFailure get(org.apache.hadoop.conf.Configuration conf)

Get the setting from configuration.

write

public static void write(ReplaceDatanodeOnFailure.Policy policy,
 boolean bestEffort,
 org.apache.hadoop.conf.Configuration conf)

Write the setting to configuration.