me.timothy.bots

Class Retryable<T>

java.lang.Object

me.timothy.bots.Retryable<T>

Type Parameters:

T - what is returned

public abstract class Retryable<T>
extends java.lang.Object

Meant to be used in anonymous classes, this retries runImpl by means of exponential back-off.

Author:

Timothy

Field Summary

Fields

Modifier and Type	Field and Description
static short	FAIL_ON_EXCEPTION Marks that this should fail on exceptions by propagating said exception.

Constructor Summary

Constructors

Constructor and Description
Retryable(java.lang.String name, java.util.List<java.lang.Runnable> failCallbacks, short... params) Instantiates a new retryable.
Retryable(java.lang.String name, java.lang.Runnable failCallback, short... params) Convenience constructor for retryables that have exactly one fail callback.
Retryable(java.lang.String name, short... params) Convenience constructor for retryables with no runnable failure callbacks.

Method Summary

Modifier and Type	Method and Description
protected void	onFailure() Called after an exception is thrown or null is returned from runImpl
T	run() Runs runImpl at most 10 times or until the result is non-null.
protected abstract T	runImpl() Run impl.

Methods inherited from class java.lang.Object

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

Field Detail

FAIL_ON_EXCEPTION

public static final short FAIL_ON_EXCEPTION

Marks that this should fail on exceptions by propagating said exception.

See Also:

Constant Field Values

Constructor Detail

Retryable

public Retryable(java.lang.String name,
                 java.util.List<java.lang.Runnable> failCallbacks,
                 short... params)

Instantiates a new retryable.

Parameters:

name - the name of the action being attempted, for debugging

failCallbacks - callbacks in the event of failure. may be null

params - optional constants that affect the behavior of the retryable

Retryable

public Retryable(java.lang.String name,
                 java.lang.Runnable failCallback,
                 short... params)

Convenience constructor for retryables that have exactly one fail callback.

Parameters:

name - the name of the action being attempted, for debugging

failCallback - the callback in the event of failure. May be null

params - optional constants that affect the behavior of the retryable

Retryable

public Retryable(java.lang.String name,
                 short... params)

Convenience constructor for retryables with no runnable failure callbacks.

Parameters:

name - the name of the action being attempted, for debugging

params - optional constants that affect the behavior of the retryable

Method Detail

run

public T run()

Runs runImpl at most 10 times or until the result is non-null.

Returns:

runImpl's non-null result upon success, null on failure

runImpl

protected abstract T runImpl()
                      throws java.lang.Exception

Run impl.

Returns:

the t

Throws:

java.lang.Exception

onFailure

protected void onFailure()

Called after an exception is thrown or null is returned from runImpl