MessageDataStore.java
/*
* Copyright (c) 2016, 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.apache.synapse.aspects.flow.statistics.store;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.synapse.aspects.flow.statistics.log.StatisticsReportingEventHolder;
import org.apache.synapse.aspects.flow.statistics.util.StatisticsConstants;
import org.apache.synapse.config.SynapseConfiguration;
import java.util.Queue;
import java.util.concurrent.ConcurrentLinkedQueue;
/**
* MessageDataCollector contains the non-blocking queue and utility methods to store and retrieve elements from the
* queue.
*/
public class MessageDataStore {
private static Log log = LogFactory.getLog(MessageDataStore.class);
/**
* Queue which holds event holder objects with collected events.
*/
private Queue<StatisticsReportingEventHolder> queue;
private String queueEvictionPolicy;
private long maxStaticsReportingQueueSize;
public MessageDataStore(SynapseConfiguration synCfg) {
queue = new ConcurrentLinkedQueue<>();
queueEvictionPolicy = synCfg.getProperty(StatisticsConstants.STATISTIC_REPORTING_QUEUE_EVICTION_POLICY,
StatisticsConstants.QUEUE_EVICTION_POLICY_NEW_MESSAGES);
maxStaticsReportingQueueSize = synCfg.getProperty(StatisticsConstants.STATISTIC_REPORTING_QUEUE_SIZE,
StatisticsConstants.MAX_STATISTIC_REPORTING_QUEUE_SIZE);
}
/**
* Add StatisticsReportingEventHolder instance to the queue
*
* @param statisticsReportingEventHolder StatisticReportingLog to be stored in the queue
*/
public void enqueue(StatisticsReportingEventHolder statisticsReportingEventHolder) {
if (queue.size() > maxStaticsReportingQueueSize) {
// This will does not add anymore
if (queueEvictionPolicy.equals(StatisticsConstants.QUEUE_EVICTION_POLICY_NEW_MESSAGES)) {
log.warn("Dropping new statistic messages since the queue is full");
return;
} else if (queueEvictionPolicy.equals(StatisticsConstants.QUEUE_EVICTION_POLICY_OLD_MESSAGES)) {
// This will dequeue old messages and enqueue new messages
log.warn("Dropping old statistic messages since the queue is full");
queue.poll();
}
}
try {
if (log.isDebugEnabled()) {
log.debug("Adding eventHolder: " + statisticsReportingEventHolder);
}
queue.add(statisticsReportingEventHolder);
} catch (Exception e) {
log.error("Error adding statistic event holder to the Queue. Dropping statistics events.");
}
}
/**
* Removes and return StatisticReportingLog from the queue
*
* @return StatisticReportingLog instance
* @throws Exception
*/
public StatisticsReportingEventHolder dequeue() throws Exception {
try {
if (log.isDebugEnabled()) {
log.debug("Polling statistics event holder object from the Queue");
}
return queue.poll();
} catch (Exception e) {
log.error("Error polling statistics event holder objects from Queue");
return null;
}
}
}