/* Copyright 2012 Thorben Lindhauer
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License 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 de.unipotsdam.hpi.thorben.observer;
import org.activiti.engine.impl.pvm.process.ActivityImpl;
import de.unipotsdam.hpi.thorben.ppi.condition.event.ConditionEvent;
/**
* We need our own Observer pattern implementation as the {@link java.lang.Observable} implementation puts state in the Observable
* that will change during process runtime (i.e. the changed-flag). As we want to observe e.g. {@link ActivityImpl} objects,
* this could lead to concurrent modifications by several executions, e.g. from different process instances, which could
* ultimately lead to undesired Observer-behavior.
* @author Thorben
*
*/
public interface Observer {
void update(ConditionEvent event);
}