Retry (reactor-core 3.3.5.RELEASE)

java.lang.Object
- reactor.util.retry.Retry

Direct Known Subclasses:

RetryBackoffSpec, RetrySpec
```
public abstract class Retry
extends Object
```
Base abstract class for a strategy to decide when to retry given a companion Flux of Retry.RetrySignal, for use with Flux.retryWhen(Retry) and Mono.retryWhen(Retry). Also provides access to configurable built-in strategies via static factory methods:
Users are encouraged to provide either concrete custom Retry strategies or builders that produce such concrete Retry. The RetrySpec returned by eg. max(long) is a good inspiration for a fluent approach that generates a Retry at each step and uses immutability/copy-on-write to enable sharing of intermediate steps (that can thus be considered templates).
Author:

Simon Baslé

Nested Class Summary

Nested Classes
Modifier and Type Class and Description

static interface Retry.RetrySignal
State for a Flux.retryWhen(Retry) Flux retry} or Mono retry.

Nested Classes
Modifier and Type	Class and Description
`static interface`	`Retry.RetrySignal` State for a `Flux.retryWhen(Retry)` Flux retry} or `Mono retry`.

Constructor Summary

Constructors
Constructor and Description

Retry()

Constructors
Constructor and Description
`Retry()`

Method Summary

All Methods Static Methods Instance Methods Abstract Methods Concrete Methods
Modifier and Type	Method and Description
`static RetryBackoffSpec`	`backoff(long maxAttempts, Duration minBackoff)` A `RetryBackoffSpec` preconfigured for exponential backoff strategy with jitter, given a maximum number of retry attempts and a minimum `Duration` for the backoff.
`static RetryBackoffSpec`	`fixedDelay(long maxAttempts, Duration fixedDelay)` A `RetryBackoffSpec` preconfigured for fixed delays (min backoff equals max backoff, no jitter), given a maximum number of retry attempts and the fixed `Duration` for the backoff.
`static Retry`	`from(Function<Flux<Retry.RetrySignal>,Publisher<?>> function)` A wrapper around `Function` to provide `Retry` by using lambda expressions.
`abstract Publisher<?>`	`generateCompanion(Flux<Retry.RetrySignal> retrySignals)` The intent of the functional `Retry` class is to let users configure how to react to `Retry.RetrySignal` by providing the operator with a companion publisher.
`static RetrySpec`	`indefinitely()` A `RetrySpec` preconfigured for the most simplistic retry strategy: retry immediately and indefinitely (similar to `Flux.retry()`).
`static RetrySpec`	`max(long max)` A `RetrySpec` preconfigured for a simple strategy with maximum number of retry attempts.
`static RetrySpec`	`maxInARow(long maxInARow)` A `RetrySpec` preconfigured for a simple strategy with maximum number of retry attempts over subsequent transient errors.

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Constructor Detail
  - Retry
```
public Retry()
```
- Method Detail
  - backoff
```
public static RetryBackoffSpec backoff(long maxAttempts,
                                       Duration minBackoff)
```
    A RetryBackoffSpec preconfigured for exponential backoff strategy with jitter, given a maximum number of retry attempts and a minimum Duration for the backoff.
    
    Parameters:
    
    maxAttempts - the maximum number of retry attempts to allow
    
    minBackoff - the minimum Duration for the first backoff
    
    Returns:
    
    the exponential backoff spec for further configuration
    
    See Also:
    
    RetryBackoffSpec.maxAttempts(long), RetryBackoffSpec.minBackoff(Duration)
  - fixedDelay
```
public static RetryBackoffSpec fixedDelay(long maxAttempts,
                                          Duration fixedDelay)
```
    A RetryBackoffSpec preconfigured for fixed delays (min backoff equals max backoff, no jitter), given a maximum number of retry attempts and the fixed Duration for the backoff.
    
    Note that calling RetryBackoffSpec.minBackoff(Duration) or RetryBackoffSpec.maxBackoff(Duration) would switch back to an exponential backoff strategy.
    
    Parameters:
    
    maxAttempts - the maximum number of retry attempts to allow
    
    fixedDelay - the Duration of the fixed delays
    
    Returns:
    
    the fixed delays spec for further configuration
    
    See Also:
    
    RetryBackoffSpec.maxAttempts(long), RetryBackoffSpec.minBackoff(Duration), RetryBackoffSpec.maxBackoff(Duration)
  - from
```
public static final Retry from(Function<Flux<Retry.RetrySignal>,Publisher<?>> function)
```
    A wrapper around Function to provide Retry by using lambda expressions.
    
    Parameters:
    
    function - the Function representing the desired Retry strategy as a lambda
    
    Returns:
    
    the Retry strategy adapted from the Function
  - generateCompanion
```
public abstract Publisher<?> generateCompanion(Flux<Retry.RetrySignal> retrySignals)
```
    The intent of the functional Retry class is to let users configure how to react to Retry.RetrySignal by providing the operator with a companion publisher. Any onNext emitted by this publisher will trigger a retry, but if that emission is delayed compared to the original signal then the attempt is delayed as well. This method generates the companion, out of a Flux of Retry.RetrySignal, which itself can serve as the simplest form of retry companion (indefinitely and immediately retry on any error).
    
    Parameters:
    
    retrySignals - the original Flux of Retry.RetrySignal, notifying of each source error that might result in a retry attempt, with context around the error and current retry cycle.
    
    Returns:
    
    the actual companion to use, which might delay or limit retry attempts
  - indefinitely
```
public static RetrySpec indefinitely()
```
    A RetrySpec preconfigured for the most simplistic retry strategy: retry immediately and indefinitely (similar to Flux.retry()).
    
    Returns:
    
    the retry indefinitely spec for further configuration
  - max
```
public static RetrySpec max(long max)
```
    A RetrySpec preconfigured for a simple strategy with maximum number of retry attempts.
    
    Parameters:
    
    max - the maximum number of retry attempts to allow
    
    Returns:
    
    the max attempt spec for further configuration
    
    See Also:
    
    RetrySpec.maxAttempts(long)
  - maxInARow
```
public static RetrySpec maxInARow(long maxInARow)
```
    A RetrySpec preconfigured for a simple strategy with maximum number of retry attempts over subsequent transient errors. An Subscriber.onNext(Object) between errors resets the counter (see RetrySpec.transientErrors(boolean)).
    
    Parameters:
    
    maxInARow - the maximum number of retry attempts to allow in a row, reset by successful onNext
    
    Returns:
    
    the max in a row spec for further configuration
    
    See Also:
    
    RetrySpec.maxAttempts(long), RetrySpec.transientErrors(boolean)

Class Retry

Nested Class Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Constructor Detail

Retry

Method Detail

backoff

fixedDelay

from

generateCompanion

indefinitely

max

maxInARow