fish.payara.microprofile.faulttolerance.service

Class FaultToleranceMethodContextImpl

java.lang.Object

fish.payara.microprofile.faulttolerance.service.FaultToleranceMethodContextImpl

All Implemented Interfaces:

FaultToleranceMethodContext

public final class FaultToleranceMethodContextImpl
extends Object
implements FaultToleranceMethodContext

The execution context for a FT annotated method. Each Method for each individual target Object (instance of the Class defining the Method) has its corresponding instance of this FaultToleranceMethodContext. When the annotated Method is invoked this implementation is bound to that context by in(InvocationContext, FaultTolerancePolicy) with a fresh instance of this class. It shares all the state with other invocations for the same method except the InvocationContext and the FaultTolerancePolicy which are specific for each invocation. This way the full FT invocation state for each method invocation is determined at the beginning of applying FT semantics and cannot change during execution (except for those counters and queues that are meant to track the shared state changes of course).

Author:

Jan Bernitt

Constructor Summary

Constructors

Constructor and Description
FaultToleranceMethodContextImpl(javax.enterprise.context.control.RequestContextController requestContext, FaultToleranceRequestTracing requestTracing, FaultToleranceMetrics metrics, ExecutorService asyncExecution, ScheduledExecutorService delayedExecution, Object target)

Method Summary

Modifier and Type	Method and Description
void	delay(long delayMillis) Delays the current thread by the given duration.
void	endTrace() Ends the innermost trace.
Object	fallbackHandle(Class<? extends org.eclipse.microprofile.faulttolerance.FallbackHandler<?>> fallbackClass, Throwable ex) Invokes the instance of the given FallbackHandler Class defined in the given context to handle the given Exception.
Object	fallbackInvoke(Method fallbackMethod) Invokes the given fallback Method in the given context.
BlockingQueue<Thread>	getConcurrentExecutions(int maxConcurrentThreads) Get or create the BlockingQueue for bulkhead.
FaultToleranceMetrics	getMetrics(boolean enabled) Returns the FaultToleranceMetrics to use.
AtomicInteger	getQueuingOrRunningPopulation() Get the bulkhead thread count.
CircuitBreakerState	getState(int requestVolumeThreshold) Get or create the CircuitBreakerState.
FaultToleranceMethodContextImpl	in(javax.interceptor.InvocationContext context, FaultTolerancePolicy policy)
boolean	isExpired(long ttl)
Object	proceed() Proceeds execution to the annotated method body.
void	runAsynchronous(CompletableFuture<Object> asyncResult, Callable<Object> task) Runs the task asynchronously and completes the given asyncResult with the its outcome.
Future<?>	runDelayed(long delayMillis, Runnable task) Runs a given task after a certain waiting time.
void	trace(String method) Starts tracing the given context named with the given method label.

Methods inherited from class java.lang.Object

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

Constructor Detail

FaultToleranceMethodContextImpl

public FaultToleranceMethodContextImpl(javax.enterprise.context.control.RequestContextController requestContext,
                                       FaultToleranceRequestTracing requestTracing,
                                       FaultToleranceMetrics metrics,
                                       ExecutorService asyncExecution,
                                       ScheduledExecutorService delayedExecution,
                                       Object target)

Method Detail

isExpired

public boolean isExpired(long ttl)

in

public FaultToleranceMethodContextImpl in(javax.interceptor.InvocationContext context,
                                          FaultTolerancePolicy policy)

proceed

public Object proceed()
               throws Exception

Description copied from interface: FaultToleranceMethodContext

Proceeds execution to the annotated method body.

Specified by:

proceed in interface FaultToleranceMethodContext

Returns:

result returned by the annotated method

Throws:

Exception - in case the annotated method threw an Exception.

getMetrics

public FaultToleranceMetrics getMetrics(boolean enabled)

Description copied from interface: FaultToleranceMethodContext

Returns the FaultToleranceMetrics to use.

Specified by:

getMetrics in interface FaultToleranceMethodContext

Parameters:

enabled - true, if metrics are enabled for the method, else false

Returns:

the FaultToleranceMetrics to use, FaultToleranceMetrics.DISABLED when not enabled.

getState

public CircuitBreakerState getState(int requestVolumeThreshold)

Description copied from interface: FaultToleranceMethodContext

Get or create the CircuitBreakerState.

Specified by:

getState in interface FaultToleranceMethodContext

Parameters:

requestVolumeThreshold - when negative no state is created if it does not already exist

Returns:

the created or existing state, or null if non existed and requestVolumeThreshold was null

getConcurrentExecutions

public BlockingQueue<Thread> getConcurrentExecutions(int maxConcurrentThreads)

Description copied from interface: FaultToleranceMethodContext

Get or create the BlockingQueue for bulkhead.

Specified by:

getConcurrentExecutions in interface FaultToleranceMethodContext

Parameters:

maxConcurrentThreads - when negative no queue is created if it does not already exist

Returns:

the created or existing queue, or null if non existed and requestVolumeThreshold was null

getQueuingOrRunningPopulation

public AtomicInteger getQueuingOrRunningPopulation()

Description copied from interface: FaultToleranceMethodContext

Get the bulkhead thread count.

Specified by:

getQueuingOrRunningPopulation in interface FaultToleranceMethodContext

Returns:

This are number of threads that are either waiting or running in the bulkhead.

delay

public void delay(long delayMillis)
           throws InterruptedException

Description copied from interface: FaultToleranceMethodContext

Delays the current thread by the given duration. The delay is traced.

Specified by:

delay in interface FaultToleranceMethodContext

Parameters:

delayMillis - the time to sleep in milliseconds

Throws:

InterruptedException - In case waiting is interrupted

runAsynchronous

public void runAsynchronous(CompletableFuture<Object> asyncResult,
                            Callable<Object> task)
                     throws RejectedExecutionException

Description copied from interface: FaultToleranceMethodContext

Runs the task asynchronously and completes the given asyncResult with the its outcome.

Specified by:

runAsynchronous in interface FaultToleranceMethodContext

Parameters:

asyncResult - a not yet completed CompletableFuture that should receive the result of the operation when it is executed

task - an operation that must compute a value of type Future or CompletionStage.

Throws:

RejectedExecutionException - In case the task could not be accepted for execution. Usually due to too many work in progress.

runDelayed

public Future<?> runDelayed(long delayMillis,
                            Runnable task)
                     throws Exception

Description copied from interface: FaultToleranceMethodContext

Runs a given task after a certain waiting time.

Specified by:

runDelayed in interface FaultToleranceMethodContext

Parameters:

delayMillis - time to wait in milliseconds before running the given task

task - operation to run

Returns:

A future that can be cancelled if the operation should no longer be run

Throws:

Exception

fallbackHandle

public Object fallbackHandle(Class<? extends org.eclipse.microprofile.faulttolerance.FallbackHandler<?>> fallbackClass,
                             Throwable ex)
                      throws Exception

Description copied from interface: FaultToleranceMethodContext

Invokes the instance of the given FallbackHandler Class defined in the given context to handle the given Exception.

Specified by:

fallbackHandle in interface FaultToleranceMethodContext

Parameters:

fallbackClass - the type of FallbackHandler to resolve or instantiate and use

ex - the Exception thrown by the FT processing to handle by the FallbackHandler

Returns:

the result returned by the invoked FallbackHandler

Throws:

Exception - in case resolving, instantiating or invoking the handler method fails

fallbackInvoke

public Object fallbackInvoke(Method fallbackMethod)
                      throws Exception

Description copied from interface: FaultToleranceMethodContext

Invokes the given fallback Method in the given context.

Specified by:

fallbackInvoke in interface FaultToleranceMethodContext

Parameters:

fallbackMethod - the Method to invoke

Returns:

the result returned by the invoked fallback method

Throws:

Exception - in case invoking the method fails or the invoked method threw an Exception

trace

public void trace(String method)

Description copied from interface: FaultToleranceMethodContext

Starts tracing the given context named with the given method label.

Specified by:

trace in interface FaultToleranceMethodContext

Parameters:

method - the label to use for the trace

endTrace

public void endTrace()

Description copied from interface: FaultToleranceMethodContext

Ends the innermost trace.

Specified by:

endTrace in interface FaultToleranceMethodContext