dev.failsafe.spi

Class PolicyExecutor<R>

java.lang.Object

dev.failsafe.spi.PolicyExecutor<R>

Type Parameters:

R - result type

public abstract class PolicyExecutor<R>
extends Object

Handles execution and execution results according to a policy. May contain pre-execution and post-execution behaviors. Each PolicyExecutor makes its own determination about whether an execution result is a success or failure.

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	PolicyExecutor(Policy<R> policy, int policyIndex)

Method Summary

Modifier and Type	Method and Description
Function<SyncExecutionInternal<R>,ExecutionResult<R>>	apply(Function<SyncExecutionInternal<R>,ExecutionResult<R>> innerFn, Scheduler scheduler) Performs an execution by calling pre-execute else calling the supplier and doing a post-execute.
Function<AsyncExecutionInternal<R>,CompletableFuture<ExecutionResult<R>>>	applyAsync(Function<AsyncExecutionInternal<R>,CompletableFuture<ExecutionResult<R>>> innerFn, Scheduler scheduler, FailsafeFuture<R> future) Performs an async execution by calling pre-execute else calling the supplier and doing a post-execute.
int	getPolicyIndex() Returns the index of the policy relative to other policies in a composition, where the innermost policy in a composition has an index of 0.
protected boolean	isFailure(ExecutionResult<R> result) Returns whether the result is a success according to the policy.
protected ExecutionResult<R>	onFailure(ExecutionContext<R> context, ExecutionResult<R> result) Performs post-execution handling for a result that is considered a failure according to isFailure(ExecutionResult), possibly creating a new result, else returning the original result.
protected CompletableFuture<ExecutionResult<R>>	onFailureAsync(ExecutionContext<R> context, ExecutionResult<R> result, Scheduler scheduler, FailsafeFuture<R> future) Performs potentially asynchrononus post-execution handling for a failed result, possibly creating a new result, else returning the original result.
protected void	onSuccess(ExecutionResult<R> result) Performs post-execution handling for a result that is considered a success according to isFailure(ExecutionResult).
ExecutionResult<R>	postExecute(ExecutionInternal<R> execution, ExecutionResult<R> result) Performs synchronous post-execution handling for a result.
protected CompletableFuture<ExecutionResult<R>>	postExecuteAsync(AsyncExecutionInternal<R> execution, ExecutionResult<R> result, Scheduler scheduler, FailsafeFuture<R> future) Performs potentially asynchronous post-execution handling for a result.
protected ExecutionResult<R>	preExecute() Called before execution to return an alternative result or exception such as if execution is not allowed or needed.
protected CompletableFuture<ExecutionResult<R>>	preExecuteAsync(Scheduler scheduler, FailsafeFuture<R> future) Called before an async execution to return an alternative result or exception such as if execution is not allowed or needed.

Methods inherited from class java.lang.Object

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

Constructor Detail

PolicyExecutor

protected PolicyExecutor(Policy<R> policy,
                         int policyIndex)

Method Detail

getPolicyIndex

public int getPolicyIndex()

Returns the index of the policy relative to other policies in a composition, where the innermost policy in a composition has an index of 0.

preExecute

protected ExecutionResult<R> preExecute()

Called before execution to return an alternative result or exception such as if execution is not allowed or needed.

preExecuteAsync

protected CompletableFuture<ExecutionResult<R>> preExecuteAsync(Scheduler scheduler,
                                                                FailsafeFuture<R> future)

Called before an async execution to return an alternative result or exception such as if execution is not allowed or needed. Returns null if pre execution is not performed. If the resulting future is completed with a non-result, then execution and post-execution should still be performed. If the resulting future is completed with null, then the execution is assumed to have been cancelled.

apply

public Function<SyncExecutionInternal<R>,ExecutionResult<R>> apply(Function<SyncExecutionInternal<R>,ExecutionResult<R>> innerFn,
                                                                   Scheduler scheduler)

Performs an execution by calling pre-execute else calling the supplier and doing a post-execute.

applyAsync

public Function<AsyncExecutionInternal<R>,CompletableFuture<ExecutionResult<R>>> applyAsync(Function<AsyncExecutionInternal<R>,CompletableFuture<ExecutionResult<R>>> innerFn,
                                                                                            Scheduler scheduler,
                                                                                            FailsafeFuture<R> future)

Performs an async execution by calling pre-execute else calling the supplier and doing a post-execute. Implementors must handle a null result from a supplier, which indicates that an async execution has occurred, that a result will be recorded separately, and that postExecute handling should not be performed.

postExecute

public ExecutionResult<R> postExecute(ExecutionInternal<R> execution,
                                      ExecutionResult<R> result)

Performs synchronous post-execution handling for a result.

postExecuteAsync

protected CompletableFuture<ExecutionResult<R>> postExecuteAsync(AsyncExecutionInternal<R> execution,
                                                                 ExecutionResult<R> result,
                                                                 Scheduler scheduler,
                                                                 FailsafeFuture<R> future)

Performs potentially asynchronous post-execution handling for a result.

isFailure

protected boolean isFailure(ExecutionResult<R> result)

Returns whether the result is a success according to the policy. If the {code result} has no result, it is not a failure.

onSuccess

protected void onSuccess(ExecutionResult<R> result)

Performs post-execution handling for a result that is considered a success according to isFailure(ExecutionResult).

onFailure

protected ExecutionResult<R> onFailure(ExecutionContext<R> context,
                                       ExecutionResult<R> result)

Performs post-execution handling for a result that is considered a failure according to isFailure(ExecutionResult), possibly creating a new result, else returning the original result.

onFailureAsync

protected CompletableFuture<ExecutionResult<R>> onFailureAsync(ExecutionContext<R> context,
                                                               ExecutionResult<R> result,
                                                               Scheduler scheduler,
                                                               FailsafeFuture<R> future)

Performs potentially asynchrononus post-execution handling for a failed result, possibly creating a new result, else returning the original result.