Package io.atlassian.fugue.retry

Class RetryFunction<F,T>

java.lang.Object

io.atlassian.fugue.retry.RetryFunction<F,T>

Type Parameters:

F - The type of the parameter the Function accepts

T - The type of the result the Function yields upon application

All Implemented Interfaces:

Function<F,T>

public class RetryFunction<F,T>
extends Object
implements Function<F,T>

A Function which wraps the apply method of another Function and attempts it up to a fixed number of times. This class can be used when a task is known to be prone to occasional failure and other workarounds are not known.

See Also:

• for a Supplier implementation
• for a Runnable implementation
• for some factory methods

Field Summary

Fields

Modifier and Type	Field	Description
private final Runnable	beforeRetry
private final Function<F,T>	function
private final ExceptionHandler	handler
private final int	tries

Constructor Summary

Constructors

Constructor	Description
RetryFunction(Function<F,T> function, int tries)	An instance that does nothing before retrying and ignores exceptions that occur.
RetryFunction(Function<F,T> function, int tries, ExceptionHandler handler)	An instance that does nothing before retrying.
RetryFunction(Function<F,T> function, int tries, ExceptionHandler handler, Runnable beforeRetry)	Constructor for RetryFunction.

Method Summary

Modifier and Type	Method	Description
T	apply(F parameter)	Attempt to apply parameter to the wrapped Function tries number of times.

Methods inherited from class java.lang.Object

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

Methods inherited from interface java.util.function.Function

andThen, compose

Field Details

function

private final Function<F,T> function

tries

private final int tries

handler

private final ExceptionHandler handler

beforeRetry

private final Runnable beforeRetry

Constructor Details

RetryFunction

public RetryFunction(Function<F,T> function,
 int tries)

An instance that does nothing before retrying and ignores exceptions that occur.

Parameters:

function - which fetches the result, must not be null

tries - the numbe rof times to attempt to get a result, must be positive

RetryFunction

public RetryFunction(Function<F,T> function,
 int tries,
 ExceptionHandler handler)

An instance that does nothing before retrying.

Parameters:

function - which fetches the result, must not be null

tries - the number of times to attempt to get a result, must be positive

handler - reacts to exceptions thrown by the supplier, must not be null

RetryFunction

public RetryFunction(Function<F,T> function,
 int tries,
 ExceptionHandler handler,
 Runnable beforeRetry)

Constructor for RetryFunction.

Parameters:

function - which fetches the result, must not be null

tries - the number of times to attempt to get a result, must be positive

handler - reacts to exceptions thrown by the supplier, must not be null

beforeRetry - an effect that is run before a retry attempt

Method Details

apply

public T apply(F parameter)

Attempt to apply parameter to the wrapped Function tries number of times. Any exceptions thrown will be ignored until the number of attempts is reached. If the number of attempts is reached without a successful result, the most recent exception to be thrown will be rethrown.

Specified by:

apply in interface Function<F,T>