org.springframework.retry.backoff

Class BackOffPolicyBuilder

java.lang.Object

org.springframework.retry.backoff.BackOffPolicyBuilder

public class BackOffPolicyBuilder
extends Object

Fluent API for creating a BackOffPolicy based on given attributes. The delay values are expressed in milliseconds. If any provided value is less than one, the resulting policy will set it to one. The default policy is a FixedBackOffPolicy with a delay of 1000ms.

Examples:

 // Default FixedBackOffPolicy with 1000ms delay
 BackOffPolicyBuilder
                .newDefaultPolicy();

 // FixedBackOffPolicy
 BackOffPolicyBuilder
                .newBuilder()
                .delay(2000)
                .build();

 // UniformRandomBackOffPolicy
 BackOffPolicyBuilder
                .newBuilder()
                .delay(500)
                .maxDelay(1000)
                .build();

 // ExponentialBackOffPolicy
 BackOffPolicyBuilder
                .newBuilder()
                .delay(1000)
                .maxDelay(5000)
                .multiplier(2)
                .build();

 // ExponentialRandomBackOffPolicy with provided Sleeper
 BackOffPolicyBuilder
                .newBuilder()
                .delay(3000)
                .maxDelay(5000)
                .multiplier(1.5)
                .random(true)
                .sleeper(mySleeper)
                .build();
 

Not thread safe. Building should be performed in a single thread. The resulting BackOffPolicy however is expected to be thread-safe and designed for moderate load concurrent access.

Since:

1.3.3

Author:

Tomaz Fernandes

Method Summary

Modifier and Type	Method and Description
BackOffPolicy	build() Builds the BackOffPolicy with the given parameters.
BackOffPolicyBuilder	delay(long delay) A canonical backoff period.
BackOffPolicyBuilder	maxDelay(long maxDelay) The maximum wait in milliseconds between retries.
BackOffPolicyBuilder	multiplier(double multiplier) If positive, then used as a multiplier for generating the next delay for backoff.
static BackOffPolicyBuilder	newBuilder() Creates a new BackOffPolicyBuilder instance.
static BackOffPolicy	newDefaultPolicy() Creates a new FixedBackOffPolicy instance with a delay of 1000ms.
BackOffPolicyBuilder	random(boolean random) In the exponential case (multiplier > 0) set this to true to have the backoff delays randomized, so that the maximum delay is multiplier times the previous delay and the distribution is uniform between the two values.
BackOffPolicyBuilder	sleeper(Sleeper sleeper) The Sleeper instance to be used to back off.

Methods inherited from class java.lang.Object

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

Method Detail

newBuilder

public static BackOffPolicyBuilder newBuilder()

Creates a new BackOffPolicyBuilder instance.

Returns:

the builder instance

newDefaultPolicy

public static BackOffPolicy newDefaultPolicy()

Creates a new FixedBackOffPolicy instance with a delay of 1000ms.

Returns:

the back off policy instance

delay

public BackOffPolicyBuilder delay(long delay)

A canonical backoff period. Used as an initial value in the exponential case, and as a minimum value in the uniform case.

Parameters:

delay - the initial or canonical backoff period in milliseconds

Returns:

this

maxDelay

public BackOffPolicyBuilder maxDelay(long maxDelay)

The maximum wait in milliseconds between retries. If less than delay(long) then a default value is applied depending on the resulting policy.

Parameters:

maxDelay - the maximum wait between retries in milliseconds

Returns:

this

multiplier

public BackOffPolicyBuilder multiplier(double multiplier)

If positive, then used as a multiplier for generating the next delay for backoff.

Parameters:

multiplier - a multiplier to use to calculate the next backoff delay

Returns:

this

random

public BackOffPolicyBuilder random(boolean random)

In the exponential case (multiplier > 0) set this to true to have the backoff delays randomized, so that the maximum delay is multiplier times the previous delay and the distribution is uniform between the two values.

Parameters:

random - the flag to signal randomization is required

Returns:

this

sleeper

public BackOffPolicyBuilder sleeper(Sleeper sleeper)

The Sleeper instance to be used to back off. Policies default to ThreadWaitSleeper.

Parameters:

sleeper - the Sleeper instance

Returns:

this

build

public BackOffPolicy build()

Builds the BackOffPolicy with the given parameters.

Returns:

the BackOffPolicy instance