org.jgroups.demos.RelayDemo 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.demos;
import org.jgroups.*;
import org.jgroups.protocols.relay.RELAY;
import org.jgroups.protocols.relay.RELAY3;
import org.jgroups.protocols.relay.RouteStatusListener;
import org.jgroups.protocols.relay.Topology;
import org.jgroups.util.ExtendedUUID;
import org.jgroups.util.UUID;
import org.jgroups.util.Util;
import java.util.List;
/** Demos RELAY. Create 2 *separate* clusters with RELAY as top protocol. Each RELAY has bridge_props="tcp.xml" (tcp.xml
* needs to be present). Then start 2 instances in the first cluster and 2 instances in the second cluster. They should
* find each other, and typing in a window should send the text to everyone, plus we should get 4 responses.
* @author Bela Ban
*/
public class RelayDemo implements Receiver {
protected static final String SITE_MASTERS="site-masters";
protected JChannel ch;
protected RELAY relay;
public static void main(String[] args) throws Exception {
String props="udp.xml";
String name=null;
boolean print_route_status=true, nohup=false;
for(int i=0; i < args.length; i++) {
if(args[i].equals("-props")) {
props=args[++i];
continue;
}
if(args[i].equals("-name")) {
name=args[++i];
continue;
}
if(args[i].equals("-print_route_status")) {
print_route_status=Boolean.parseBoolean(args[++i]);
continue;
}
if(args[i].equals("-nohup")) {
nohup=true;
continue;
}
System.out.println("RelayDemo [-props props] [-name name] [-print_route_status false|true] [-nohup]");
return;
}
RelayDemo demo=new RelayDemo();
demo.start(props, name, print_route_status, nohup);
}
public void receive(Message msg) {
Address sender=msg.getSrc();
System.out.println("<< " + msg.getObject() + " from " + sender);
Address dst=msg.getDest();
if(dst == null) {
Message rsp=new ObjectMessage(msg.getSrc(), "response");
try {
ch.send(rsp);
}
catch(Exception e) {
e.printStackTrace();
}
}
}
public void viewAccepted(View new_view) {
System.out.println(print(new_view));
}
protected void start(String props, String name, boolean print_route_status, boolean nohup) throws Exception {
ExtendedUUID.setPrintFunction(UUID::printName);
ch=new JChannel(props).setReceiver(this);
if(name != null)
ch.setName(name);
relay=ch.getProtocolStack().findProtocol(RELAY.class);
if(relay == null)
throw new IllegalStateException(String.format("Protocol %s not found", RELAY.class.getSimpleName()));
String site_name=relay.site();
if(print_route_status) {
relay.setRouteStatusListener(new RouteStatusListener() {
public void sitesUp(String... sites) {
System.out.printf("-- %s: site(s) %s came up\n",
ch.getAddress(), String.join(", ", sites));
}
public void sitesDown(String... sites) {
System.out.printf("-- %s: site(s) %s went down\n",
ch.getAddress(), String.join(", ", sites));
}
public void sitesUnreachable(String... sites) {
System.out.printf("-- %s: site(s) %s are unreachable\n",
ch.getAddress(), String.join(", ", sites));
}
});
}
ch.connect(site_name);
if(!nohup) {
eventLoop(ch);
Util.close(ch);
}
}
protected void eventLoop(JChannel ch) {
for(;;) {
try {
String line=Util.readStringFromStdin(": ");
if(line == null)
break;
if(process(line)) // see if we have a command, otherwise pass down
continue;
ObjectMessage msg=new ObjectMessage(null, line);
ch.send(msg);
}
catch(Throwable t) {
t.printStackTrace();
}
}
}
protected boolean process(String line) {
if(line == null || line.isEmpty())
return true;
if(line.equalsIgnoreCase(SITE_MASTERS) || line.equalsIgnoreCase("sm")) {
System.out.printf("site masters in %s: %s\n", relay.site(), relay.siteMasters());
return true;
}
if(line.equalsIgnoreCase("help")) {
help();
return true;
}
if(line.equalsIgnoreCase("mbrs")) {
System.out.printf("%s: local members: %s\n", relay.getAddress(), relay.members());
return true;
}
if(line.equalsIgnoreCase("sites")) {
System.out.printf("configured sites: %s\n", relay.getSites());
return true;
}
if(line.startsWith("topo") && relay instanceof RELAY3) {
String sub=line.substring("topo".length()).trim();
String site=null;
if(sub != null && !sub.isEmpty()) {
String[] tmp=sub.split(" ");
site=tmp.length > 0 && !tmp[0].isEmpty()? tmp[0].trim() : null;
}
Topology topo=relay.topo().removeAll(site != null? List.of(site) : null)
.refresh(site);
Util.sleep(100);
System.out.printf("\n%s\n", topo.print(site));
return true;
}
return false;
}
protected static void help() {
System.out.println("\ncommands:" +
"\nhelp" +
"\nmbrs: prints the local members" +
"\nsite-masters (sm): prints the site masters of this site" +
"\nsites: prints the configured sites" +
"\ntopo: prints the topology (site masters and local members of all sites)\n");
}
protected static String print(View view) {
StringBuilder sb=new StringBuilder();
boolean first=true;
sb.append(view.getClass().getSimpleName() + ": ").append(view.getViewId()).append(": ");
for(Address mbr: view.getMembers()) {
if(first)
first=false;
else
sb.append(", ");
sb.append(mbr);
}
return sb.toString();
}
}