/*
* Copyright 2012-2013 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.worker;
import com.amazonaws.services.simpleworkflow.flow.DecisionContext;
import com.amazonaws.services.simpleworkflow.flow.DecisionContextProviderImpl;
import com.amazonaws.services.simpleworkflow.flow.WorkflowExecutionLocal;
/**
* Holds DecisionContext for currently executing decision task. Do not use this
* class directly. Instead use {@link DecisionContextProviderImpl}.
*/
public abstract class CurrentDecisionContext {
private final static WorkflowExecutionLocal<DecisionContext> CURRENT = new WorkflowExecutionLocal<DecisionContext>();
/**
* retrieves the current DecisionContext for a particular thread
*
* @return current decider context being used for the decision
* @throws IllegalStateException
* if this method is called outside the scope of workflow
* definition.
*/
public static DecisionContext get() {
DecisionContext result = CURRENT.get();
if (result == null) {
throw new IllegalStateException(
"No context found. It means that the method is called outside of the workflow definition code.");
}
return result;
}
/**
* @return if context is set which means that code is executed as part of
* the decision.
*/
public static boolean isSet() {
return CURRENT.get() != null;
}
public static void set(DecisionContext context) {
if (context == null) {
throw new IllegalArgumentException("null context");
}
WorkflowExecutionLocal.before();
CURRENT.set(context);
}
public static void unset() {
WorkflowExecutionLocal.after();
}
}