Package com.helixframework.retry

Class Retry

java.lang.Object

com.helixframework.retry.Retry

public final class Retry
extends Object

Wrapper function that retries, with exponential backoff and jitter, in the event of an exception.

Field Summary

Fields

Modifier and Type	Field	Description
static final Long	DEFAULT_INITIAL_BACKOFF	Default number of milliseconds to initially wait for the retry backoff.
static final int	DEFAULT_MAX_RETRIES	Default number of retries attempted by this function before throwing RetriesExhaustedException.

Method Summary

Modifier and Type	Method	Description
static <T> T	execute(RetryableFunction<T> fn)	Executes the wrapped function with default maximum number of retries in the event of an exception.
static <T> T	execute(RetryableFunction<T> fn, int maxRetries)	Executes the wrapped function with the specified maximum number of retries in the event of an exception.
static <T> T	execute(RetryableFunction<T> fn, int maxRetries, Long initialBackoff)	Executes the wrapped function with the specified maximum number of retries, and an initial backoff, in the event of an exception.
static <T> T	execute(RetryableFunction<T> fn, int maxRetries, Long initialBackoff, Collection<Class<? extends Throwable>> expectedErrors)	Executes the wrapped function, terminating immediately if one of the expected errors is encountered, otherwise the function will be retried up to the specified maximum number of retries.
static <T> T	execute(RetryableFunction<T> fn, int maxRetries, Long initialBackoff, Supplier<T> fallback)	Executes the wrapped function.
static <T> T	execute(RetryableFunction<T> fn, int maxRetries, Long initialBackoff, Supplier<T> fallback, Collection<Class<? extends Throwable>> expectedErrors)	Executes the provided RetryableFunction with the given parameters.
static <T> T	execute(RetryableFunction<T> fn, int maxRetries, Collection<Class<? extends Throwable>> expectedErrors)	Executes the wrapped function, terminating immediately if one of the expected errors is encountered, otherwise the function will be retried up to the specified maximum number of retries.
static <T> T	execute(RetryableFunction<T> fn, int maxRetries, Supplier<T> fallback)	Executes the wrapped function.
static <T> T	execute(RetryableFunction<T> fn, Collection<Class<? extends Throwable>> expectedErrors)	Executes the wrapped function, terminating immediately if one of the expected errors is encountered.
static <T> T	execute(RetryableFunction<T> fn, Supplier<T> fallback)	Executes the wrapped function.

Methods inherited from class java.lang.Object

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

Field Details

DEFAULT_MAX_RETRIES

public static final int DEFAULT_MAX_RETRIES

Default number of retries attempted by this function before throwing RetriesExhaustedException.

See Also:

• Constant Field Values

DEFAULT_INITIAL_BACKOFF

public static final Long DEFAULT_INITIAL_BACKOFF

Default number of milliseconds to initially wait for the retry backoff.

Method Details

execute

public static <T> T execute(RetryableFunction<T> fn)
                     throws RetriesExhaustedException

Executes the wrapped function with default maximum number of retries in the event of an exception.

Type Parameters:

T - return type of the wrapped function

Parameters:

fn - wrapped function to execute

Returns:

result of the wrapped function

Throws:

RetriesExhaustedException - if the maximum number of retries has been reached

execute

public static <T> T execute(RetryableFunction<T> fn,
 int maxRetries)
                     throws RetriesExhaustedException

Executes the wrapped function with the specified maximum number of retries in the event of an exception.

Type Parameters:

T - return type of the wrapped function

Parameters:

fn - wrapped function to execute

maxRetries - maximum number of times to retry the wrapped function in the event of an exception

Returns:

result of the wrapped function

Throws:

RetriesExhaustedException - if the maximum number of retries has been reached

execute

public static <T> T execute(RetryableFunction<T> fn,
 int maxRetries,
 Long initialBackoff)
                     throws RetriesExhaustedException

Executes the wrapped function with the specified maximum number of retries, and an initial backoff, in the event of an exception.

Type Parameters:

T - return type of the wrapped function

Parameters:

fn - wrapped function to execute

maxRetries - maximum number of times to retry the wrapped function in the event of an exception

initialBackoff - number of milliseconds to initially wait for backoff

Returns:

result of the wrapped function

Throws:

RetriesExhaustedException - if the maximum number of retries has been reached

execute

public static <T> T execute(RetryableFunction<T> fn,
 Collection<Class<? extends Throwable>> expectedErrors)
                     throws RetriesExhaustedException

Executes the wrapped function, terminating immediately if one of the expected errors is encountered.

Type Parameters:

T - return type of the wrapped function

Parameters:

fn - wrapped function to execute

expectedErrors - a collection of errors that when encountered will cause the function to fail immediately without exhausting the maximum number of retries

Returns:

result of the wrapped function

Throws:

RetriesExhaustedException - if the maximum number of retries has been reached

execute

public static <T> T execute(RetryableFunction<T> fn,
 int maxRetries,
 Collection<Class<? extends Throwable>> expectedErrors)
                     throws RetriesExhaustedException

Executes the wrapped function, terminating immediately if one of the expected errors is encountered, otherwise the function will be retried up to the specified maximum number of retries.

Type Parameters:

T - return type of the wrapped function

Parameters:

fn - wrapped function to execute

maxRetries - maximum number of times to retry the wrapped function in the event of an exception not specified in the expectedErrors

expectedErrors - a collection of errors that when encountered will cause the function to fail immediately without exhausting the maximum number of retries

Returns:

result of the wrapped function

Throws:

RetriesExhaustedException - if the maximum number of retries has been reached

execute

public static <T> T execute(RetryableFunction<T> fn,
 int maxRetries,
 Long initialBackoff,
 Collection<Class<? extends Throwable>> expectedErrors)
                     throws RetriesExhaustedException

Executes the wrapped function, terminating immediately if one of the expected errors is encountered, otherwise the function will be retried up to the specified maximum number of retries.

Type Parameters:

T - return type of the wrapped function

Parameters:

fn - wrapped function to execute

maxRetries - maximum number of times to retry the wrapped function in the event of an exception not specified in the expectedErrors

initialBackoff - number of milliseconds to initially wait for backoff

expectedErrors - a collection of errors that when encountered will cause the function to fail immediately without exhausting the maximum number of retries

Returns:

result of the wrapped function

Throws:

RetriesExhaustedException - if the maximum number of retries has been reached

IllegalArgumentException - if maxRetries is negative or initialBackoff is negative

execute

public static <T> T execute(RetryableFunction<T> fn,
 Supplier<T> fallback)

Executes the wrapped function. In the event that all retries are exhausted, executes the fallback function.

Type Parameters:

T - return type of the wrapped function

Parameters:

fn - wrapped function to execute

fallback - fallback Supplier to use if retries are exhausted

Returns:

result of the wrapped function

execute

public static <T> T execute(RetryableFunction<T> fn,
 int maxRetries,
 Supplier<T> fallback)

Executes the wrapped function. In the event that all retries are exhausted, executes the fallback function.

Type Parameters:

T - return type of the wrapped function

Parameters:

fn - wrapped function to execute

maxRetries - the maximum number of times to retry the RetryableFunction in the event of an exception

fallback - fallback Supplier to use if retries are exhausted

Returns:

result of the wrapped function

Throws:

IllegalArgumentException - if maxRetries is negative or fallback is null

execute

public static <T> T execute(RetryableFunction<T> fn,
 int maxRetries,
 Long initialBackoff,
 Supplier<T> fallback)

Executes the wrapped function. In the event that all retries are exhausted, executes the fallback function.

Type Parameters:

T - return type of the wrapped function

Parameters:

fn - wrapped function to execute

maxRetries - the maximum number of times to retry the RetryableFunction in the event of an exception

initialBackoff - number of milliseconds to initially wait for backoff

fallback - fallback Supplier to use if retries are exhausted

Returns:

result of the wrapped function

Throws:

IllegalArgumentException - if maxRetries is negative, initialBackoff is negative, or fallback is null

execute

public static <T> T execute(RetryableFunction<T> fn,
 int maxRetries,
 Long initialBackoff,
 Supplier<T> fallback,
 Collection<Class<? extends Throwable>> expectedErrors)

Executes the provided RetryableFunction with the given parameters.

Type Parameters:

T - the return type of the wrapped function

Parameters:

fn - the RetryableFunction to execute

maxRetries - the maximum number of times to retry the wrapped function in the event of an exception

initialBackoff - number of milliseconds to initially wait for backoff

fallback - the fallback Supplier to use if retries are exhausted

expectedErrors - a collection of errors that will cause the function to fail immediately without exhausting the maximum number of retries

Returns:

the result of the wrapped function, or the result of the fallback Supplier if retries are exhausted

Throws:

IllegalArgumentException - if maxRetries is negative, initialBackoff is negative, or fallback is null