| /* |
| * Licensed to the Apache Software Foundation (ASF) under one |
| * or more contributor license agreements. See the NOTICE file |
| * distributed with this work for additional information |
| * regarding copyright ownership. The ASF 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.gossip.manager; |
| |
| import java.io.IOException; |
| import java.net.DatagramPacket; |
| import java.net.DatagramSocket; |
| import java.net.InetSocketAddress; |
| import java.net.SocketAddress; |
| import java.net.SocketException; |
| import java.util.concurrent.atomic.AtomicBoolean; |
| |
| import org.apache.gossip.model.Base; |
| import org.apache.log4j.Logger; |
| |
| import com.fasterxml.jackson.databind.ObjectMapper; |
| |
| /** |
| * [The passive thread: reply to incoming gossip request.] This class handles the passive cycle, |
| * where this client has received an incoming message. For now, this message is always the |
| * membership list, but if you choose to gossip additional information, you will need some logic to |
| * determine the incoming message. |
| */ |
| abstract public class PassiveGossipThread implements Runnable { |
| |
| public static final Logger LOGGER = Logger.getLogger(PassiveGossipThread.class); |
| |
| /** The socket used for the passive thread of the gossip service. */ |
| private final DatagramSocket server; |
| |
| private final AtomicBoolean keepRunning; |
| |
| private final String cluster; |
| |
| private final ObjectMapper MAPPER = new ObjectMapper(); |
| |
| private final GossipCore gossipCore; |
| |
| public PassiveGossipThread(GossipManager gossipManager, GossipCore gossipCore) { |
| this.gossipCore = gossipCore; |
| try { |
| SocketAddress socketAddress = new InetSocketAddress(gossipManager.getMyself().getUri().getHost(), |
| gossipManager.getMyself().getUri().getPort()); |
| server = new DatagramSocket(socketAddress); |
| LOGGER.debug("Gossip service successfully initialized on port " |
| + gossipManager.getMyself().getUri().getPort()); |
| LOGGER.debug("I am " + gossipManager.getMyself()); |
| cluster = gossipManager.getMyself().getClusterName(); |
| if (cluster == null){ |
| throw new IllegalArgumentException("cluster was null"); |
| } |
| } catch (SocketException ex) { |
| LOGGER.warn(ex); |
| throw new RuntimeException(ex); |
| } |
| keepRunning = new AtomicBoolean(true); |
| } |
| |
| @Override |
| public void run() { |
| while (keepRunning.get()) { |
| try { |
| byte[] buf = new byte[server.getReceiveBufferSize()]; |
| DatagramPacket p = new DatagramPacket(buf, buf.length); |
| server.receive(p); |
| int packet_length = UdpUtil.readPacketLengthFromBuffer(buf); |
| if (packet_length <= GossipManager.MAX_PACKET_SIZE) { |
| byte[] json_bytes = new byte[packet_length]; |
| for (int i = 0; i < packet_length; i++) { |
| json_bytes[i] = buf[i + 4]; |
| } |
| debug(packet_length, json_bytes); |
| try { |
| Base activeGossipMessage = MAPPER.readValue(json_bytes, Base.class); |
| gossipCore.receive(activeGossipMessage); |
| } catch (RuntimeException ex) {//TODO trap json exception |
| LOGGER.error("Unable to process message", ex); |
| } |
| } else { |
| LOGGER.error("The received message is not of the expected size, it has been dropped."); |
| } |
| |
| } catch (IOException e) { |
| LOGGER.error(e); |
| keepRunning.set(false); |
| } |
| } |
| shutdown(); |
| } |
| |
| private void debug(int packetLength, byte[] jsonBytes) { |
| if (LOGGER.isDebugEnabled()){ |
| String receivedMessage = new String(jsonBytes); |
| LOGGER.debug("Received message (" + packetLength + " bytes): " |
| + receivedMessage); |
| } |
| } |
| |
| public void shutdown() { |
| try { |
| server.close(); |
| } catch (RuntimeException ex) { |
| } |
| } |
| |
| } |