/*
* Copyright (c) 2005-2008, WSO2 Inc. (http://www.wso2.org) All Rights Reserved.
*
* WSO2 Inc. licenses this file to you 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 org.wso2.carbon.das.messageflow.data.publisher.observer;
import org.apache.synapse.aspects.flow.statistics.publishing.PublishingFlow;
/**
* This interface can be used to register consumers into the MediationStatisticsStore
* and retrieve statistics updates from the data store.
*/
public interface MessageFlowObserver {
/**
* Clean up this observer and prepare for shutdown
*/
public void destroy();
/**
* Receive a statistics update from the statistics store/provider. The cumulative records
* received from this method will be 'null' for the very first update sent by the data
* store. This is because for the very first update there are no cumulative data in the
* store. The implementations of this method should not attempt to modify the provided
* StatisticsRecord instances. If such modifications are necessary the StatisticsRecord
* objects should be first copied using the copy constructor. Also implementations of the
* updateStatistics method should finish quickly. Long running tasks should be executed using
* separate threads to prevent the notifier thread getting blocked.
*
* @param snapshot Current latest update containing resource specific data, category specific
* data, cumulative data and error logs
*/
public void updateStatistics(PublishingFlow snapshot);
}