com.lightstep.tracer.retry

Class RetryPolicy

java.lang.Object

com.lightstep.tracer.retry.RetryPolicy

All Implemented Interfaces:

Serializable

Direct Known Subclasses:

ExponentialBackoffRetryPolicy, LinearDelayRetryPolicy

public abstract class RetryPolicy
extends Object
implements Serializable

A policy that defines the conditions and timing of when retries should be performed.

The retryOn(Exception) method specifies the exception conditions of when a retry should occur.

The run(Retryable) method is the entrypoint for a Retryable object to be executed.

See Also:

Serialized Form

Constructor Summary

Constructors

Constructor and Description
RetryPolicy(int maxRetries, double jitter) Creates a new RetryPolicy with the specified maxRetries value.

Method Summary

Modifier and Type	Method and Description
abstract long	getDelayMs(int attemptNo) Returns the delay in milliseconds for the specified attempt number.
int	getMaxRetries() Returns the number of retry attempts allowed by this RetryPolicy.
protected boolean	retryOn(Exception e) Specifies the exception conditions of when a retry should occur.
<T> T	run(Retryable<T> retryable) The entrypoint for a Retryable object to be executed.
<T> T	run(Retryable<T> retryable, long timeout) The entrypoint for a Retryable object to be executed.

Methods inherited from class java.lang.Object

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

Constructor Detail

RetryPolicy

public RetryPolicy(int maxRetries,
                   double jitter)

Creates a new RetryPolicy with the specified maxRetries value.

Parameters:

maxRetries - A positive value representing the number of retry attempts allowed by the RetryPolicy.

jitter - The factor multiplier to be applied to getDelayMs(int) to thereafter be added to the delay for each retry.

Throws:

IllegalArgumentException - If maxRetries or jitter is negative.

Method Detail

retryOn

protected boolean retryOn(Exception e)

Specifies the exception conditions of when a retry should occur.

Parameters:

e - The exception that occurred during execution of a Retryable object.

Returns:

true if a retry should occur, otherwise false.

run

public final <T> T run(Retryable<T> retryable)
                throws RetryFailureException

The entrypoint for a Retryable object to be executed. Exceptions in Retryable.retry(RetryPolicy,int) will be considered for retry if the number of maxRetries has not been exceeded, and retryOn(Exception) returns true.

Type Parameters:

T - The type of the result object.

Parameters:

retryable - The Retryable object to run.

Returns:

The resulting value from Retryable.retry(RetryPolicy,int).

Throws:

RetryFailureException - If retry attempts have exceeded maxRetries, or if retryOn(Exception) returns false.

NullPointerException - If retryable is null.

run

public final <T> T run(Retryable<T> retryable,
                       long timeout)
                throws RetryFailureException

The entrypoint for a Retryable object to be executed. Exceptions in Retryable.retry(RetryPolicy,int) will be considered for retry if the number of maxRetries has not been exceeded, and retryOn(Exception) returns true.

Type Parameters:

T - The type of the result object.

Parameters:

retryable - The Retryable object to run.

timeout - The maximum time to retry in milliseconds.

Returns:

The resulting value from Retryable.retry(RetryPolicy,int).

Throws:

RetryFailureException - If retry attempts have exceeded maxRetries, if retryOn(Exception) returns false, or if timeout is exceeded.

IllegalArgumentException - If timeout is negative.

NullPointerException - If the value of timeout is negative.

getMaxRetries

public int getMaxRetries()

Returns the number of retry attempts allowed by this RetryPolicy.

Returns:

The number of retry attempts allowed by this RetryPolicy.

getDelayMs

public abstract long getDelayMs(int attemptNo)

Returns the delay in milliseconds for the specified attempt number. This method is intended to be implemented by a subclass to define the backoff function for retry attempts.

Parameters:

attemptNo - The attempt number, starting with 1.

Returns:

The delay in milliseconds for the specified attempt number.