Package dev.failsafe

Class ExecutionImpl<R>

java.lang.Object

dev.failsafe.ExecutionImpl<R>

Type Parameters:

R - result type

All Implemented Interfaces:

ExecutionContext<R>, ExecutionInternal<R>

Direct Known Subclasses:

AsyncExecutionImpl, SyncExecutionImpl

class ExecutionImpl<R>
extends Object
implements ExecutionInternal<R>

Execution and ExecutionInternal implementation.

Field Summary

Fields

Modifier and Type	Field	Description
(package private) boolean	attemptRecorded
private final AtomicInteger	attempts
private Instant	attemptStartTime
(package private) CheckedRunnable	cancelCallback
(package private) int	cancelledIndex
(package private) boolean	completed
private final AtomicInteger	executions
private final AtomicReference<ExecutionInternal<R>>	latest
(package private) final List<PolicyExecutor<R>>	policyExecutors
private boolean	preExecuted
private final ExecutionResult<R>	previousResult
(package private) ExecutionResult<R>	result
private Instant	startTime

Constructor Summary

Constructors

Constructor	Description
ExecutionImpl(ExecutionImpl<R> execution)	Create an execution for a new attempt.
ExecutionImpl(ExecutionResult<R> previousResult)	Used for testing purposes only
ExecutionImpl(List<? extends Policy<R>> policies)	Creates a new execution for the policies.

Method Summary

Modifier and Type	Method	Description
boolean	cancel()	Called indirectly by users.
void	cancel(PolicyExecutor<R> policyExecutor)	Called by policies.
int	getAttemptCount()	Gets the number of execution attempts so far, including attempts that are blocked before being executed, such as when a CircuitBreaker is open.
Duration	getElapsedAttemptTime()	Returns the elapsed time since the last execution attempt began.
Duration	getElapsedTime()	Returns the elapsed time since initial execution began.
int	getExecutionCount()	Gets the number of completed executions so far.
<T extends Throwable> T	getLastException()	Returns the last exception that was recorded else null.
R	getLastResult()	Returns the last result that was recorded else null.
R	getLastResult(R defaultValue)	Returns the last result that was recorded else the defaultValue.
ExecutionInternal<R>	getLatest()	Returns the most recent execution to be attempted.
Object	getLock()	Returns a lock object that is common across all execution attempts.
ExecutionResult<R>	getResult()	Returns the recorded result for an execution attempt.
Instant	getStartTime()	Returns the time that the initial execution started.
boolean	isCancelled()	Returns whether the execution has been cancelled.
boolean	isCancelled(PolicyExecutor<R> policyExecutor)	Returns whether the execution is considered cancelled for the policyExecutor.
boolean	isFirstAttempt()	Returns true when an execution result has not yet been recorded, meaning this is the first execution attempt.
boolean	isPreExecuted()	Returns whether the execution has been pre-executed, indicating the attempt has started.
boolean	isRetry()	Returns true when an execution result has already been recorded, meaning the execution is being retried.
void	onCancel(CheckedRunnable cancelCallback)	Sets the cancelCallback to be called if the execution is cancelled, such as by the resulting Call or CompletableFuture, or a Timeout.
(package private) ExecutionResult<R>	postExecute(ExecutionResult<R> result)	Externally called.
void	preExecute()	Called when execution of the user's supplier is about to begin.
void	record(ExecutionResult<R> result)	Records the result if the execution has been pre-executed and a result has not already been recorded.
void	recordAttempt()	Records an execution attempt which may correspond with an execution result.
String	toString()

Methods inherited from class java.lang.Object

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

Field Details

policyExecutors

final List<PolicyExecutor<R>> policyExecutors

startTime

private volatile Instant startTime

attempts

private final AtomicInteger attempts

executions

private final AtomicInteger executions

latest

private final AtomicReference<ExecutionInternal<R>> latest

previousResult

private final ExecutionResult<R> previousResult

result

volatile ExecutionResult<R> result

attemptStartTime

private volatile Instant attemptStartTime

cancelledIndex

volatile int cancelledIndex

cancelCallback

volatile CheckedRunnable cancelCallback

preExecuted

private volatile boolean preExecuted

attemptRecorded

volatile boolean attemptRecorded

completed

volatile boolean completed

Constructor Details

ExecutionImpl

ExecutionImpl(List<? extends Policy<R>> policies)

Creates a new execution for the policies.

ExecutionImpl

ExecutionImpl(ExecutionImpl<R> execution)

Create an execution for a new attempt.

ExecutionImpl

ExecutionImpl(ExecutionResult<R> previousResult)

Used for testing purposes only

Method Details

getResult

public ExecutionResult<R> getResult()

Description copied from interface: ExecutionInternal

Returns the recorded result for an execution attempt.

Specified by:

getResult in interface ExecutionInternal<R>

onCancel

public void onCancel(CheckedRunnable cancelCallback)

Description copied from interface: ExecutionContext

Sets the cancelCallback to be called if the execution is cancelled, such as by the resulting Call or CompletableFuture, or a Timeout. Any exception thrown by the cancelCallback is ignored.

Specified by:

onCancel in interface ExecutionContext<R>

preExecute

public void preExecute()

Description copied from interface: ExecutionInternal

Called when execution of the user's supplier is about to begin.

Specified by:

preExecute in interface ExecutionInternal<R>

isPreExecuted

public boolean isPreExecuted()

Description copied from interface: ExecutionInternal

Returns whether the execution has been pre-executed, indicating the attempt has started.

Specified by:

isPreExecuted in interface ExecutionInternal<R>

recordAttempt

public void recordAttempt()

Description copied from interface: ExecutionInternal

Records an execution attempt which may correspond with an execution result. Async executions will have results recorded separately.

Specified by:

recordAttempt in interface ExecutionInternal<R>

record

public void record(ExecutionResult<R> result)

Description copied from interface: ExecutionInternal

Records the result if the execution has been pre-executed and a result has not already been recorded.

Specified by:

record in interface ExecutionInternal<R>

postExecute

ExecutionResult<R> postExecute(ExecutionResult<R> result)

Externally called. Records an execution and performs post-execution handling for the result against all configured policy executors. Returns whether the result is complete for all policies.

Throws:

IllegalStateException - if the execution is already complete

cancel

public boolean cancel()

Called indirectly by users.

Specified by:

cancel in interface ExecutionInternal<R>

Returns:

whether cancellation was successful or not. Returns false if the execution was already cancelled or completed.

cancel

public void cancel(PolicyExecutor<R> policyExecutor)

Called by policies.

Specified by:

cancel in interface ExecutionInternal<R>

isCancelled

public boolean isCancelled()

Description copied from interface: ExecutionContext

Returns whether the execution has been cancelled. In this case the implementor should attempt to stop execution.

Specified by:

isCancelled in interface ExecutionContext<R>

isCancelled

public boolean isCancelled(PolicyExecutor<R> policyExecutor)

Description copied from interface: ExecutionInternal

Returns whether the execution is considered cancelled for the policyExecutor.

Specified by:

isCancelled in interface ExecutionInternal<R>

getLock

public Object getLock()

Description copied from interface: ExecutionInternal

Returns a lock object that is common across all execution attempts. Useful for guarding against races when mutating an execution.

Specified by:

getLock in interface ExecutionInternal<R>

getLatest

public ExecutionInternal<R> getLatest()

Description copied from interface: ExecutionInternal

Returns the most recent execution to be attempted.

Specified by:

getLatest in interface ExecutionInternal<R>

getElapsedTime

public Duration getElapsedTime()

Description copied from interface: ExecutionContext

Returns the elapsed time since initial execution began.

Specified by:

getElapsedTime in interface ExecutionContext<R>

getElapsedAttemptTime

public Duration getElapsedAttemptTime()

Description copied from interface: ExecutionContext

Returns the elapsed time since the last execution attempt began.

Specified by:

getElapsedAttemptTime in interface ExecutionContext<R>

getAttemptCount

public int getAttemptCount()

Description copied from interface: ExecutionContext

Gets the number of execution attempts so far, including attempts that are blocked before being executed, such as when a CircuitBreaker is open. Will return 0 when the first attempt is in progress or has yet to begin.

Specified by:

getAttemptCount in interface ExecutionContext<R>

getExecutionCount

public int getExecutionCount()

Description copied from interface: ExecutionContext

Gets the number of completed executions so far. Executions that are blocked, such as when a CircuitBreaker is open, are not counted. Will return 0 when the first attempt is in progress or has yet to begin.

Specified by:

getExecutionCount in interface ExecutionContext<R>

getLastException

public <T extends Throwable> T getLastException()

Description copied from interface: ExecutionContext

Returns the last exception that was recorded else null.

Specified by:

getLastException in interface ExecutionContext<R>

getLastResult

public R getLastResult()

Description copied from interface: ExecutionContext

Returns the last result that was recorded else null.

Specified by:

getLastResult in interface ExecutionContext<R>

getLastResult

public R getLastResult(R defaultValue)

Description copied from interface: ExecutionContext

Returns the last result that was recorded else the defaultValue.

Specified by:

getLastResult in interface ExecutionContext<R>

getStartTime

public Instant getStartTime()

Description copied from interface: ExecutionContext

Returns the time that the initial execution started.

Specified by:

getStartTime in interface ExecutionContext<R>

isFirstAttempt

public boolean isFirstAttempt()

Description copied from interface: ExecutionContext

Returns true when an execution result has not yet been recorded, meaning this is the first execution attempt.

Specified by:

isFirstAttempt in interface ExecutionContext<R>

isRetry

public boolean isRetry()

Description copied from interface: ExecutionContext

Returns true when an execution result has already been recorded, meaning the execution is being retried.

Specified by:

isRetry in interface ExecutionContext<R>

toString

public String toString()

Overrides:

toString in class Object