/*
* Copyright 2012 Amazon.com, Inc. or its affiliates. All Rights Reserved.
*
* Licensed under the Apache License, Version 2.0 (the "License"). You may not
* use this file except in compliance with the License. A copy of the License is
* located at
*
* http://aws.amazon.com/apache2.0
*
* or in the "license" file accompanying this file. This file is distributed on
* an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either
* express or implied. See the License for the specific language governing
* permissions and limitations under the License.
*/
package com.amazonaws.services.simpleworkflow.flow.aspectj;
import java.util.Arrays;
import org.aspectj.lang.ProceedingJoinPoint;
import org.aspectj.lang.Signature;
import org.aspectj.lang.annotation.Around;
import org.aspectj.lang.annotation.Aspect;
import org.aspectj.lang.reflect.MethodSignature;
import com.amazonaws.services.simpleworkflow.flow.DecisionContextProviderImpl;
import com.amazonaws.services.simpleworkflow.flow.WorkflowClock;
import com.amazonaws.services.simpleworkflow.flow.annotations.ExponentialRetry;
import com.amazonaws.services.simpleworkflow.flow.core.Promise;
import com.amazonaws.services.simpleworkflow.flow.core.Settable;
import com.amazonaws.services.simpleworkflow.flow.interceptors.AsyncExecutor;
import com.amazonaws.services.simpleworkflow.flow.interceptors.AsyncRetryingExecutor;
import com.amazonaws.services.simpleworkflow.flow.interceptors.AsyncRunnable;
import com.amazonaws.services.simpleworkflow.flow.interceptors.ExponentialRetryPolicy;
/**
* This class is for internal use only and may be changed or removed without prior notice.
*
*/
@Aspect
public class ExponentialRetryAspect {
@SuppressWarnings({ "rawtypes", "unchecked" })
private final class DecoratorInvocationHandler implements AsyncRunnable {
private final ProceedingJoinPoint pjp;
private final Settable result;
public DecoratorInvocationHandler(ProceedingJoinPoint pjp, Settable result) {
this.pjp = pjp;
this.result = result;
}
@Override
public void run() throws Throwable {
if (result != null) {
result.unchain();
result.chain((Promise) pjp.proceed());
} else {
pjp.proceed();
}
}
}
@Around("execution(@com.amazonaws.services.simpleworkflow.flow.annotations.ExponentialRetry * *(..)) && @annotation(retryAnnotation)")
public Object retry(final ProceedingJoinPoint pjp, ExponentialRetry retryAnnotation) throws Throwable {
ExponentialRetryPolicy retryPolicy = createExponentialRetryPolicy(retryAnnotation);
WorkflowClock clock = new DecisionContextProviderImpl().getDecisionContext().getWorkflowClock();
AsyncExecutor executor = new AsyncRetryingExecutor(retryPolicy, clock);
Settable<?> result;
if (isVoidReturnType(pjp)) {
result = null;
}
else {
result = new Settable<Object>();
}
DecoratorInvocationHandler handler = new DecoratorInvocationHandler(pjp, result);
executor.execute(handler);
return result;
}
private boolean isVoidReturnType(final ProceedingJoinPoint pjp) {
boolean isVoidReturnType = false;
final Signature signature = pjp.getStaticPart().getSignature();
if (signature instanceof MethodSignature) {
final MethodSignature methodSignature = (MethodSignature) signature;
isVoidReturnType = (methodSignature != null) ? Void.TYPE.equals(methodSignature.getReturnType()) : false;
}
return isVoidReturnType;
}
private ExponentialRetryPolicy createExponentialRetryPolicy(ExponentialRetry retryAnnotation) {
ExponentialRetryPolicy retryPolicy = new ExponentialRetryPolicy(retryAnnotation.initialRetryIntervalSeconds()).withExceptionsToRetry(
Arrays.asList(retryAnnotation.exceptionsToRetry())).withExceptionsToExclude(
Arrays.asList(retryAnnotation.excludeExceptions())).withBackoffCoefficient(retryAnnotation.backoffCoefficient()).withMaximumRetryIntervalSeconds(
retryAnnotation.maximumRetryIntervalSeconds()).withRetryExpirationIntervalSeconds(
retryAnnotation.retryExpirationSeconds()).withMaximumAttempts(retryAnnotation.maximumAttempts());
retryPolicy.validate();
return retryPolicy;
}
}