Package io.helidon.common.reactive

Interface RetrySchema

Functional Interface:

This is a functional interface and can therefore be used as the assignment target for a lambda expression or method reference.

@FunctionalInterface
public interface RetrySchema

Defines delay for next read/poll operation in a polling publisher.

Schema defines a delay before next poll if the last one did not get new data.

It is possible to use included static factory methods for some standard schemas.

Method Summary

Modifier and Type	Method	Description
static RetrySchema	constant(long delay)	Creates the retry schema with a constant result.
static RetrySchema	geometric(long firstDelay, double ratio, long maxDelay)	Creates the retry schema as a bounded geometric series.
static RetrySchema	linear(long firstDelay, long delayIncrement, long maxDelay)	Creates the retry schema with a linear delay increment.
long	nextDelay(int retryCount, long lastDelay)	Returns a delay before next read if the last one poll did not get new data.

Method Detail

nextDelay

long nextDelay(int retryCount,
               long lastDelay)

Returns a delay before next read if the last one poll did not get new data.

Parameters:

retryCount - a count of already poll retries. It is 0 when called first time and resets every time when poll returns some data.

lastDelay - a last returned value. 0 in first call. Resets when some data are get.

Returns:

a delay in milliseconds before next poll attempt. If less then zero then Publisher completes with onError message.

linear

static RetrySchema linear(long firstDelay,
                          long delayIncrement,
                          long maxDelay)

Creates the retry schema with a linear delay increment. It returns firstDelay for the first call and then it increments it's value for every call by delayIncrement until reach a limit defined by maxDelay.

Parameters:

firstDelay - a delay to returns for the first call

delayIncrement - an increment of the returned value.

maxDelay - the maximal value to return

Returns:

computed retry delay with a linear increment

constant

static RetrySchema constant(long delay)

Creates the retry schema with a constant result.

Parameters:

delay - a constant delay to return

Returns:

a delay value

geometric

static RetrySchema geometric(long firstDelay,
                             double ratio,
                             long maxDelay)

Creates the retry schema as a bounded geometric series.

Parameters:

firstDelay - a delay to returns for the first call

ratio - a geometric series ratio

maxDelay - the maximal value to return

Returns:

computed retry delay