Package oracle.nosql.driver

Class DefaultRetryHandler

java.lang.Object

oracle.nosql.driver.DefaultRetryHandler

All Implemented Interfaces:

RetryHandler

public class DefaultRetryHandler
extends Object
implements RetryHandler

Default retry handler. This may be extended by clients for specific use cases. The default retry handler decides when and for how long retries will be attempted. See RetryHandler for more information on retry handlers.

Method Summary

Modifier and Type	Method	Description
static int	computeBackoffDelay(Request request, int fixedDelayMs)	Compute an incremental backoff delay in milliseconds.
void	delay(Request request, int numRetries, RetryableException re)	Delay (sleep) during retry cycle.
boolean	doRetry(Request request, int numRetries, RetryableException re)	Decide whether to retry or not.
int	getNumRetries()	Returns the number of retries that this handler instance will allow before the exception is thrown to the application.

Methods inherited from class java.lang.Object

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

Method Detail

getNumRetries

public int getNumRetries()

Description copied from interface: RetryHandler

Returns the number of retries that this handler instance will allow before the exception is thrown to the application.

Specified by:

getNumRetries in interface RetryHandler

Returns:

the max number of retries

doRetry

public boolean doRetry(Request request,
                       int numRetries,
                       RetryableException re)

Decide whether to retry or not. Default behavior is to *not* retry OperationThrottlingException because the retry time is likely much longer than normal because they are DDL operations. Read and Write throttling exceptions are always retryable. Otherwise check the request itself to see if it should not be retried.

Specified by:

doRetry in interface RetryHandler

Parameters:

request - the Request that has triggered the exception

numRetries - the number of retries that have occurred for the operation

re - the exception that was thrown

Returns:

true if the operation should be retried, false if not, causing the exception to be thrown to the application.

delay

public void delay(Request request,
                  int numRetries,
                  RetryableException re)

Delay (sleep) during retry cycle. If delayMS is non-zero, use it. Otherwise, use an incremental backoff algorithm to compute the time of delay.

Specified by:

delay in interface RetryHandler

Parameters:

request - the Request that has triggered the exception

numRetries - the number of retries that have occurred for the operation

re - the exception that was thrown

computeBackoffDelay

public static int computeBackoffDelay(Request request,
                                      int fixedDelayMs)

Compute an incremental backoff delay in milliseconds. This method also checks the request's timeout and ensures the delay will not exceed the specified timeout.

Parameters:

request - The request object being executed

fixedDelayMs - A specific delay to use and check for timeout. Pass zero to use the default backoff logic.

Returns:

The number of milliseconds to delay. If zero, do not delay at all.