Java tutorial
/* * Copyright 2015-present Open Networking Foundation * * 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 org.onosproject.provider.of.meter.impl; import org.onlab.util.Timer; import org.onosproject.openflow.controller.OpenFlowSwitch; import org.onosproject.openflow.controller.RoleState; import org.projectfloodlight.openflow.protocol.OFMeterStatsRequest; import org.slf4j.Logger; import io.netty.util.Timeout; import io.netty.util.TimerTask; import java.util.concurrent.TimeUnit; import static org.slf4j.LoggerFactory.getLogger; /* * Sends Meter Stats Request and collect the Meter statistics with a time interval. */ public class MeterStatsCollector implements TimerTask { private final OpenFlowSwitch sw; private final Logger log = getLogger(getClass()); private final int refreshInterval; private Timeout timeout; private boolean stopTimer = false; /** * Creates a GroupStatsCollector object. * * @param sw Open Flow switch * @param interval time interval for collecting group statistic */ public MeterStatsCollector(OpenFlowSwitch sw, int interval) { this.sw = sw; this.refreshInterval = interval; } @Override public void run(Timeout timeout) throws Exception { if (!sw.isConnected()) { log.debug("Switch {} disconnected. Aborting meter stats collection", sw.getStringId()); return; } log.trace("Collecting stats for {}", sw.getStringId()); sendMeterStatisticRequest(); if (!this.stopTimer) { log.trace("Scheduling stats collection in {} seconds for {}", this.refreshInterval, this.sw.getStringId()); timeout.timer().newTimeout(this, refreshInterval, TimeUnit.SECONDS); } } public void sendMeterStatisticRequest() { if (log.isTraceEnabled()) { log.trace("sendMeterStatistics {}:{}", sw.getStringId(), sw.getRole()); } if (sw.getRole() != RoleState.MASTER) { return; } OFMeterStatsRequest.Builder builder = sw.factory().buildMeterStatsRequest(); builder.setXid(0).setMeterId(0xFFFFFFFF); sw.sendMsg(builder.build()); } /** * Starts the collector. */ public void start() { log.info("Starting Meter Stats collection thread for {}", sw.getStringId()); timeout = Timer.newTimeout(this, 1, TimeUnit.SECONDS); } /** * Stops the collector. */ public void stop() { log.info("Stopping Meter Stats collection thread for {}", sw.getStringId()); this.stopTimer = true; timeout.cancel(); } }