Package org.kiwiproject.retry

Class SimpleRetries

java.lang.Object

org.kiwiproject.retry.SimpleRetries

public class SimpleRetries
extends Object

Static utilities for retrying an operation. The Supplier passed to each method must indicate success or failure. Success is indicated by returning a non-null value. Failure is indicated by returning null or by throwing an exception. Each time a failure occurs, the code sleeps for the specified delay time, and then another attempt will be made unless the maximum number of attempts has been reached.

While you can use this directly, consider using SimpleRetryer, which is more flexible because (1) you can easily mock it in tests, and (2) it accepts common configuration options and makes the method calls simpler because there are many fewer arguments.

Constructor Summary

Constructors

Constructor	Description
SimpleRetries()

Method Summary

Modifier and Type	Method	Description
static <T> Optional<T>	tryGetObject(int maxAttempts, long retryDelay, TimeUnit retryDelayUnit, Class<T> type, Supplier<T> supplier)	Try to get an object, making up to maxAttempts attempts.
static <T> Optional<T>	tryGetObject(int maxAttempts, long retryDelay, TimeUnit retryDelayUnit, Supplier<T> supplier)	Try to get an object, making up to maxAttempts attempts.
static <T> Optional<T>	tryGetObject(int maxAttempts, long retryDelay, TimeUnit retryDelayUnit, KiwiEnvironment environment, Class<T> type, Supplier<T> supplier)	Try to get an object, making up to maxAttempts attempts.
static <T> Optional<T>	tryGetObject(int maxAttempts, long retryDelay, TimeUnit retryDelayUnit, KiwiEnvironment environment, String type, org.slf4j.event.Level level, Supplier<T> supplier)	Try to get an object, making up to maxAttempts attempts.
static <T> Optional<T>	tryGetObject(int maxAttempts, long retryDelay, TimeUnit retryDelayUnit, KiwiEnvironment environment, Supplier<T> supplier)	Try to get an object, making up to maxAttempts attempts.
static <T> RetryResult<T>	tryGetObjectCollectingErrors(int maxAttempts, long retryDelay, TimeUnit retryDelayUnit, Class<T> type, Supplier<T> supplier)	Try to get an object, making up to maxAttempts attempts.
static <T> RetryResult<T>	tryGetObjectCollectingErrors(int maxAttempts, long retryDelay, TimeUnit retryDelayUnit, Supplier<T> supplier)	Try to get an object, making up to maxAttempts attempts.
static <T> RetryResult<T>	tryGetObjectCollectingErrors(int maxAttempts, long retryDelay, TimeUnit retryDelayUnit, KiwiEnvironment environment, Class<T> type, Supplier<T> supplier)	Try to get an object, making up to maxAttempts attempts.
static <T> RetryResult<T>	tryGetObjectCollectingErrors(int maxAttempts, long retryDelay, TimeUnit retryDelayUnit, KiwiEnvironment environment, String type, Supplier<T> supplier)	Try to get an object, making up to maxAttempts attempts.
static <T> RetryResult<T>	tryGetObjectCollectingErrors(int maxAttempts, long retryDelay, TimeUnit retryDelayUnit, KiwiEnvironment environment, String type, org.slf4j.event.Level level, Supplier<T> supplier)	Try to get an object, making up to maxAttempts attempts.

Methods inherited from class java.lang.Object

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

Constructor Detail

SimpleRetries

public SimpleRetries()

Method Detail

tryGetObject

public static <T> Optional<T> tryGetObject(int maxAttempts,
                                           long retryDelay,
                                           TimeUnit retryDelayUnit,
                                           Supplier<T> supplier)

Try to get an object, making up to maxAttempts attempts. Logs first attempt and retries at TRACE level.

Type Parameters:

T - the type of object

Parameters:

maxAttempts - the maximum number of attempts to make before giving up

retryDelay - constant delay time between attempts

retryDelayUnit - delay time unit between attempts

supplier - on success return the object; return null or throw exception if attempt failed

Returns:

an Optional which either contains a value, or is empty if all attempts failed

tryGetObject

public static <T> Optional<T> tryGetObject(int maxAttempts,
                                           long retryDelay,
                                           TimeUnit retryDelayUnit,
                                           KiwiEnvironment environment,
                                           Supplier<T> supplier)

Try to get an object, making up to maxAttempts attempts. Logs first attempt and retries at TRACE level using "object" as the description.

Type Parameters:

T - the type of object

Parameters:

maxAttempts - the maximum number of attempts to make before giving up

retryDelay - constant delay time between attempts

retryDelayUnit - delay time unit between attempts

environment - the KiwiEnvironment to use when sleeping between attempts

supplier - on success return the object; return null or throw exception if attempt failed

Returns:

an Optional which either contains a value, or is empty if all attempts failed

tryGetObject

public static <T> Optional<T> tryGetObject(int maxAttempts,
                                           long retryDelay,
                                           TimeUnit retryDelayUnit,
                                           Class<T> type,
                                           Supplier<T> supplier)

Try to get an object, making up to maxAttempts attempts. Logs first attempt and retries at TRACE level using the given type as the description.

Type Parameters:

T - the type of object

Parameters:

maxAttempts - the maximum number of attempts to make before giving up

retryDelay - constant delay time between attempts

retryDelayUnit - delay time unit between attempts

type - the type of object we are attempting to return, used when logging attempts

supplier - on success return the object; return null or throw exception if attempt failed

Returns:

an Optional which either contains a value, or is empty if all attempts failed

tryGetObject

public static <T> Optional<T> tryGetObject(int maxAttempts,
                                           long retryDelay,
                                           TimeUnit retryDelayUnit,
                                           KiwiEnvironment environment,
                                           Class<T> type,
                                           Supplier<T> supplier)

Try to get an object, making up to maxAttempts attempts. Logs first attempt and retries at TRACE level, using the given type as the description.

Type Parameters:

T - the type of object

Parameters:

maxAttempts - the maximum number of attempts to make before giving up

retryDelay - constant delay time between attempts

retryDelayUnit - delay time unit between attempts

environment - the KiwiEnvironment to use when sleeping between attempts

type - the type of object we are attempting to return, used when logging attempts

supplier - on success return the object; return null or throw exception if attempt failed

Returns:

an Optional which either contains a value, or is empty if all attempts failed

tryGetObject

public static <T> Optional<T> tryGetObject(int maxAttempts,
                                           long retryDelay,
                                           TimeUnit retryDelayUnit,
                                           KiwiEnvironment environment,
                                           String type,
                                           org.slf4j.event.Level level,
                                           Supplier<T> supplier)

Try to get an object, making up to maxAttempts attempts. Logs first attempt at TRACE level, and logs retries at the given level, always using type as the description.

Type Parameters:

T - the type of object

Parameters:

maxAttempts - the maximum number of attempts to make before giving up

retryDelay - constant delay time between attempts

retryDelayUnit - delay time unit between attempts

environment - the KiwiEnvironment to use when sleeping between attempts

type - the type of object we are attempting to return, used when logging attempts

level - the SLF4J log Level at which to log retries

supplier - on success return the object; return null or throw exception if attempt failed

Returns:

an Optional which either contains a value, or is empty if all attempts failed

tryGetObjectCollectingErrors

public static <T> RetryResult<T> tryGetObjectCollectingErrors(int maxAttempts,
                                                              long retryDelay,
                                                              TimeUnit retryDelayUnit,
                                                              Supplier<T> supplier)

Try to get an object, making up to maxAttempts attempts. Logs first attempt and retries at TRACE level using "object" as the description.

Type Parameters:

T - the type of object

Parameters:

maxAttempts - the maximum number of attempts to make before giving up

retryDelay - constant delay time between attempts

retryDelayUnit - delay time unit between attempts

supplier - on success return the object; return null or throw exception if attempt failed

Returns:

a RetryResult

tryGetObjectCollectingErrors

public static <T> RetryResult<T> tryGetObjectCollectingErrors(int maxAttempts,
                                                              long retryDelay,
                                                              TimeUnit retryDelayUnit,
                                                              Class<T> type,
                                                              Supplier<T> supplier)

Try to get an object, making up to maxAttempts attempts. Logs first attempt and retries at TRACE level using the given type as the description.

Type Parameters:

T - the type of object

Parameters:

maxAttempts - the maximum number of attempts to make before giving up

retryDelay - constant delay time between attempts

retryDelayUnit - delay time unit between attempts

type - the type of object we are attempting to return, used when logging attempts

supplier - on success return the object; return null or throw exception if attempt failed

Returns:

a RetryResult

tryGetObjectCollectingErrors

public static <T> RetryResult<T> tryGetObjectCollectingErrors(int maxAttempts,
                                                              long retryDelay,
                                                              TimeUnit retryDelayUnit,
                                                              KiwiEnvironment environment,
                                                              Class<T> type,
                                                              Supplier<T> supplier)

Try to get an object, making up to maxAttempts attempts. Logs first attempt and retries at TRACE level using the given type as the description.

Type Parameters:

T - the type of object

Parameters:

maxAttempts - the maximum number of attempts to make before giving up

retryDelay - constant delay time between attempts

retryDelayUnit - delay time unit between attempts

environment - the KiwiEnvironment to use when sleeping between attempts

type - the type of object we are attempting to return, used when logging attempts

supplier - on success return the object; return null or throw exception if attempt failed

Returns:

a RetryResult

tryGetObjectCollectingErrors

public static <T> RetryResult<T> tryGetObjectCollectingErrors(int maxAttempts,
                                                              long retryDelay,
                                                              TimeUnit retryDelayUnit,
                                                              KiwiEnvironment environment,
                                                              String type,
                                                              Supplier<T> supplier)

Try to get an object, making up to maxAttempts attempts. Logs first attempt and retries at TRACE level using the given type as the description.

Type Parameters:

T - the type of object

Parameters:

maxAttempts - the maximum number of attempts to make before giving up

retryDelay - constant delay time between attempts

retryDelayUnit - delay time unit between attempts

environment - the KiwiEnvironment to use when sleeping between attempts

type - the type of object we are attempting to return, used when logging attempts

supplier - on success return the object; return null or throw exception if attempt failed

Returns:

a RetryResult

tryGetObjectCollectingErrors

public static <T> RetryResult<T> tryGetObjectCollectingErrors(int maxAttempts,
                                                              long retryDelay,
                                                              TimeUnit retryDelayUnit,
                                                              KiwiEnvironment environment,
                                                              String type,
                                                              org.slf4j.event.Level level,
                                                              Supplier<T> supplier)

Try to get an object, making up to maxAttempts attempts. Logs first attempt at TRACE level and logs retries at the given level, always using type as the description.

Type Parameters:

T - the type of object

Parameters:

maxAttempts - the maximum number of attempts to make before giving up

retryDelay - constant delay time between attempts

retryDelayUnit - delay time unit between attempts

environment - the KiwiEnvironment to use when sleeping between attempts

type - the type of object we are attempting to return, used when logging attempts

level - the SLF4J log Level at which to log retries

supplier - on success return the object; return null or throw exception if attempt failed

Returns:

a RetryResult