package org.apache.s4.comm.udp;
import java.io.IOException;
import java.net.DatagramPacket;
import java.net.DatagramSocket;
import java.net.InetAddress;
import java.net.SocketException;
import java.util.HashMap;
import java.util.Map;
import org.apache.s4.base.Emitter;
import org.apache.s4.comm.topology.ClusterNode;
import org.apache.s4.comm.topology.Topology;
import org.apache.s4.comm.topology.TopologyChangeListener;
import com.google.common.collect.HashBiMap;
import com.google.inject.Inject;
public class UDPEmitter implements Emitter, TopologyChangeListener {
private DatagramSocket socket;
private final HashBiMap<Integer, ClusterNode> nodes;
private final Map<Integer, InetAddress> inetCache = new HashMap<Integer, InetAddress>();
private final long messageDropInQueueCount = 0;
private final Topology topology;
public long getMessageDropInQueueCount() {
return messageDropInQueueCount;
}
@Inject
public UDPEmitter(Topology topology) {
this.topology = topology;
topology.addListener(this);
nodes = HashBiMap.create(topology.getTopology().getNodes().size());
for (ClusterNode node : topology.getTopology().getNodes()) {
nodes.forcePut(node.getPartition(), node);
}
try {
socket = new DatagramSocket();
} catch (SocketException se) {
throw new RuntimeException(se);
}
}
@Override
public boolean send(int partitionId, byte[] message) {
try {
ClusterNode node = nodes.get(partitionId);
if (node == null) {
throw new RuntimeException(String.format("Bad partition id %d", partitionId));
}
byte[] byteBuffer = new byte[message.length];
System.arraycopy(message, 0, byteBuffer, 0, message.length);
InetAddress inetAddress = inetCache.get(partitionId);
if (inetAddress == null) {
inetAddress = InetAddress.getByName(node.getMachineName());
inetCache.put(partitionId, inetAddress);
}
DatagramPacket dp = new DatagramPacket(byteBuffer, byteBuffer.length, inetAddress, node.getPort());
socket.send(dp);
} catch (IOException e) {
throw new RuntimeException(e);
}
return true;
}
@Override
public int getPartitionCount() {
return topology.getTopology().getPartitionCount();
}
@Override
public void onChange() {
// topology changes when processes pick tasks
synchronized (nodes) {
for (ClusterNode clusterNode : topology.getTopology().getNodes()) {
Integer partition = clusterNode.getPartition();
nodes.put(partition, clusterNode);
}
}
}
}