/**
* Multi-cast a message to all nodes with a specific role.
*
* @param role Destination role
* @param msg Message to send
* @param expected Number of nodes to multicast
* @return Success code
*/
public int multicast(PaxosRole.Role role, PaxosMessage msg, int expected) {
// Get all the nodes in the network.
Map<String, StaticNetwork.Route> routes = network.getAllRoutes();
int i = 0;
for (String id : routes.keySet()) {
if (!id.equals(home)) {
// Make sure that we are not sending to a client.
if (role != PaxosRole.Role.CLIENT && !network.isClientConnection(id)) {
StaticNetwork.Route route = routes.get(id);
msg.setDestination(role);
pipeline.startClient(route.ip, route.port, msg);
// Increment the number of messages sent.
++i;
}
}
// Only send the minimum necessary.
if (i == expected) {
break;
}
}
return PaxosCommunicator.SUCCESS;
}
/**
* Send a specific message to the supplied role.
*
* @param destination Destination role
* @param msg Message to send
*/
public void send(PaxosRole destination, PaxosMessage msg) {
StaticNetwork.Route route = network.getRoute(destination.getID());
if (route != null) {
msg.setDestination(destination.getType());
pipeline.startClient(route.ip, route.port, msg);
}
}
/**
* Send a message to a non-specific node with the specified role. Usually this means sending to a
* local role on the same node, unless the sending role is already on the node.
*/
public void send(PaxosRole sender, PaxosRole.Role role, PaxosMessage msg) {
// Ask the network for the "desired" target. Depending on the
// network implementation, this could be the "leader", etc.
StaticNetwork.Route route = network.getDesirable(home);
if (route != null) {
msg.setDestination(role);
pipeline.startClient(route.ip, route.port, msg);
}
}
/**
* Start listening for network communication.
*
* @param id ID identifying the listening node.
*/
public void startListening(String id) {
home = id;
StaticNetwork.Route route = network.getRoute(id);
if (route != null) {
if (pipeline.startServer(route.port)) {
logger.log(Level.INFO, String.format("%s: listening port %d", id, route.port));
}
}
}
/**
* Multi-cast a message to all nodes with a specific role.
*
* @param role Destination role
* @param msg Message to send
* @param policy Quorum policy
* @return Success code
*/
public int multicast(PaxosRole.Role role, PaxosMessage msg, Quorum policy) {
// Get the number of nodes necessary for a quorum.
int expected = getQuorum(network.getNumNodes(), policy);
return multicast(role, msg, expected);
}