org.jgroups.protocols.relay.Relayer2 Maven / Gradle / Ivy
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This artifact provides a single jar that contains all classes required to use remote EJB and JMS, including
all dependencies. It is intended for use by those not using maven, maven users should just import the EJB and
JMS BOM's instead (shaded JAR's cause lots of problems with maven, as it is very easy to inadvertently end up
with different versions on classes on the class path).
package org.jgroups.protocols.relay;
import org.jgroups.*;
import org.jgroups.logging.Log;
import org.jgroups.protocols.relay.config.RelayConfig;
import org.jgroups.stack.AddressGenerator;
import org.jgroups.util.UUID;
import org.jgroups.util.Util;
import java.util.*;
import java.util.concurrent.ConcurrentLinkedQueue;
/**
* Maintains bridges and routing table. Does the routing of outgoing messages and dispatches incoming messages to
* the right members.
* A Relayer cannot be reused once it is stopped, but a new Relayer instance must be created.
* @author Bela Ban
* @since 3.2
*/
public class Relayer2 extends Relayer {
/** The bridges which are used to connect to different sites */
protected final Collection bridges=new ConcurrentLinkedQueue<>();
public Relayer2(RELAY2 relay, Log log) {
super(relay, log);
}
/**
* Creates all bridges from site_config and connects them (joining the bridge clusters)
* @param bridge_configs A list of bridge configurations
* @param bridge_name The name of the local bridge channel, prefixed with '_'.
* @param my_site_id The ID of this site
* @throws Throwable
*/
public void start(List bridge_configs, String bridge_name, final String my_site_id)
throws Throwable {
if(done) {
log.trace(relay.getAddress() + ": will not start the Relayer as stop() has been called");
return;
}
try {
for(RelayConfig.BridgeConfig bridge_config: bridge_configs) {
Bridge bridge=new Bridge(bridge_config.createChannel(), bridge_config.getClusterName(), bridge_name,
new AddressGenerator() {
@Override public Address generateAddress() {
return new SiteUUID(UUID.randomUUID(), bridge_name, my_site_id);
}
@Override public Address generateAddress(String name) {
return new SiteUUID(UUID.randomUUID(), name, my_site_id);
}
});
bridges.add(bridge);
}
for(Bridge bridge: bridges)
bridge.start();
}
catch(Throwable t) {
stop();
throw t;
}
finally {
if(done) {
log.trace(relay.getAddress() + ": stop() was called while starting the relayer; stopping the relayer now");
stop();
}
}
}
/**
* Disconnects and destroys all bridges
*/
public void stop() {
done=true;
bridges.forEach(Bridge::stop);
bridges.clear();
}
protected View getBridgeView(String cluster_name) {
if(cluster_name == null || bridges == null)
return null;
for(Bridge bridge: bridges) {
if(Objects.equals(bridge.cluster_name, cluster_name))
return bridge.view;
}
return null;
}
protected class Bridge implements Receiver {
protected JChannel channel;
protected final String cluster_name;
protected View view;
protected Bridge(final JChannel ch, final String cluster, String name, AddressGenerator gen) throws Exception {
this.channel=ch;
this.channel.setName(name);
this.channel.setReceiver(this);
this.channel.addAddressGenerator(gen);
this.cluster_name=cluster;
}
protected void start() throws Exception {
channel.connect(cluster_name);
log.info("%s: joined bridge cluster '%s'", channel.getAddress(), cluster_name);
}
protected void stop() {
log.info("%s: leaving bridge cluster '%s'", channel.getAddress(), channel.getClusterName());
Util.close(channel);
}
public void receive(Message msg) {
RelayHeader hdr=msg.getHeader(relay.getId());
if(hdr == null) {
log.warn("received a message without a relay header; discarding it");
return;
}
switch(hdr.type) {
case RelayHeader.TOPO_REQ:
RelayHeader rsp_hdr=new RelayHeader(RelayHeader.TOPO_RSP)
.addToSites(((RELAY2)relay).printLocalTopology());
Message topo_rsp=new EmptyMessage(msg.src()).putHeader(relay.getId(), rsp_hdr);
try {
channel.send(topo_rsp);
}
catch(Exception e) {
log.warn("%s: failed sending TOPO-RSP message to %s: %s", channel.getAddress(), msg.src(), e);
}
return; // not relayed
case RelayHeader.TOPO_RSP:
Set sites=hdr.getSites();
if(sites != null && !sites.isEmpty())
((RELAY2)relay).topo_collector.add(msg.src(), sites.iterator().next());
return;
}
relay.handleRelayMessage(msg);
}
/** The view contains a list of SiteUUIDs. Adjust the routing table based on the SiteUUIDs UUID and site */
public void viewAccepted(View new_view) {
this.view=new_view;
log.trace("[Relayer " + channel.getAddress() + "] view: " + new_view);
Map> tmp=extract(new_view);
Set down=new HashSet<>(routes.keySet());
Set up=new HashSet<>();
down.removeAll(tmp.keySet());
routes.keySet().retainAll(tmp.keySet()); // remove all sites which are not in the view
for(Map.Entry> entry: tmp.entrySet()) {
String key=entry.getKey();
List val=entry.getValue();
List newRoutes;
if(routes.containsKey(key))
newRoutes=new ArrayList<>(routes.get(key));
else {
newRoutes=new ArrayList<>();
if(up != null)
up.add(key);
}
// Remove routes not in the view anymore:
newRoutes.removeIf(route -> !val.contains(route.siteMaster()));
// Add routes that aren't yet in the routing table:
val.stream().filter(addr -> !contains(newRoutes, addr))
.forEach(addr -> newRoutes.add(new Route(addr, channel, relay, log).stats(stats)));
if(newRoutes.isEmpty()) {
routes.remove(key);
down.add(key);
up.remove(key);
}
else
routes.put(key, Collections.unmodifiableList(newRoutes));
}
if(!down.isEmpty())
relay.sitesChange(true, down);
if(!up.isEmpty())
relay.sitesChange(false, up);
}
protected boolean contains(List routes, Address addr) {
return routes.stream().anyMatch(route -> route.siteMaster().equals(addr));
}
/** Returns a map containing the site keys and addresses as values */
protected Map> extract(View view) {
Map> map=new HashMap<>(view.size());
for(Address mbr: view) {
SiteAddress member=(SiteAddress)mbr;
String key=member.getSite();
List list=map.computeIfAbsent(key, k -> new ArrayList<>());
if(!list.contains(member))
list.add(member);
}
return map;
}
}
}