Package org.apache.hadoop.io.retry

Interface FailoverProxyProvider<T>

All Superinterfaces:

java.lang.AutoCloseable, java.io.Closeable

All Known Implementing Classes:

DefaultFailoverProxyProvider

@Evolving
public interface FailoverProxyProvider<T>
extends java.io.Closeable

An implementer of this interface is capable of providing proxy objects for use in IPC communication, and potentially modifying these objects or creating entirely new ones in the event of certain types of failures. The determination of whether or not to fail over is handled by RetryPolicy.

Nested Class Summary

Nested Classes

Modifier and Type	Interface	Description
static class	FailoverProxyProvider.ProxyInfo<T>

Method Summary

Modifier and Type	Method	Description
java.lang.Class<T>	getInterface()	Return a reference to the interface this provider's proxy objects actually implement.
FailoverProxyProvider.ProxyInfo<T>	getProxy()	Get the proxy object which should be used until the next failover event occurs.
void	performFailover(T currentProxy)	Called whenever the associated RetryPolicy determines that an error warrants failing over.

Methods inherited from interface java.io.Closeable

close

Method Detail

getProxy

FailoverProxyProvider.ProxyInfo<T> getProxy()

Get the proxy object which should be used until the next failover event occurs.

Returns:

the proxy object to invoke methods upon

performFailover

void performFailover(T currentProxy)

Called whenever the associated RetryPolicy determines that an error warrants failing over.

Parameters:

currentProxy - the proxy object which was being used before this failover event

getInterface

java.lang.Class<T> getInterface()

Return a reference to the interface this provider's proxy objects actually implement. If any of the methods on this interface are annotated as being Idempotent or AtMostOnce, then this fact will be passed to the RetryPolicy.shouldRetry(Exception, int, int, boolean) method on error, for use in determining whether or not failover should be attempted.

Returns:

the interface implemented by the proxy objects returned by getProxy()