org.jgroups.protocols.LOCAL_PING 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;
import org.jgroups.*;
import org.jgroups.annotations.ManagedAttribute;
import org.jgroups.annotations.ManagedOperation;
import org.jgroups.util.NameCache;
import org.jgroups.util.Responses;
import org.jgroups.util.Tuple;
import java.util.ArrayList;
import java.util.List;
import java.util.Map;
import java.util.Objects;
import java.util.concurrent.ConcurrentHashMap;
import java.util.function.Function;
/**
* Discovery protocol for finding members in the local process only. Doesn't send discovery requests and responses, but
* fetches discovery information directly from a hashmap. Used mainly by unit test.
* @author Bela Ban
* @since 4.1.3
*/
public class LOCAL_PING extends Discovery {
/** Map of cluster names and address-protocol mappings. Used for routing messages to all or single members */
protected static final Map> discovery=new ConcurrentHashMap<>();
protected static final Function> FUNC=k -> new ArrayList<>();
public boolean isDynamic() {
return true;
}
public void stop() {
super.stop();
}
@ManagedOperation(description="Dumps the contents of the discovery cache")
public static String print() {
StringBuilder sb=new StringBuilder();
synchronized(discovery) {
for(Map.Entry> e : discovery.entrySet())
sb.append(e.getKey()).append(": ").append(e.getValue()).append("\n");
}
return sb.toString();
}
@ManagedAttribute(description="Number of keys in the discovery cache")
public static int getDiscoveryCacheSize() {
synchronized(discovery) {
return discovery.size();
}
}
public Responses findMembers(List members, boolean initial_discovery, boolean async, long timeout) {
return super.findMembers(members, initial_discovery, false, timeout);
}
@Override
public void findMembers(List members, boolean initial_discovery, Responses responses) {
num_discovery_requests++;
synchronized(discovery) {
List list=discovery.get(cluster_name);
if(list != null) {
list.forEach(d -> {
addAddressToLocalCache(d.sender, d.physical_addr);
responses.addResponse(d, false);
});
}
}
// responses.done(); // so waitFor() doesn't block at all
}
public Object down(Event evt) {
if(evt.type() == Event.VIEW_CHANGE && cluster_name != null) {
Address old_coord=view != null? view.getCoord() : null;
boolean was_coord=Objects.equals(local_addr, old_coord);
Object retval=super.down(evt);
// synchronize TP.logical_addr_cache with discovery cache
synchronized(discovery) {
List list=discovery.get(cluster_name);
if(list != null && !list.isEmpty()) {
for(PingData d : list) {
Address mbr=d.getAddress();
if(down_prot.down(new Event(Event.GET_PHYSICAL_ADDRESS, mbr)) == null)
down_prot.down(new Event(Event.ADD_PHYSICAL_ADDRESS, new Tuple<>(mbr, d.getPhysicalAddr())));
// set the coordinator based on the new view (https://issues.redhat.com/browse/JGRP-2381)
if(Objects.equals(local_addr, mbr)) {
if(!was_coord && is_coord) { // this member became coordinator
d.coord(true);
log.trace("%s: became coordinator (view: %s)", local_addr, view);
}
if(was_coord && !is_coord) { // this member ceased to be coord, e.g. on a merge
d.coord(false);
log.trace("%s: ceased to be coordinator (view: %s)", local_addr, view);
}
}
}
}
}
return retval;
}
return super.down(evt);
}
public void handleConnect() {
if(cluster_name == null || local_addr == null)
throw new IllegalStateException("cluster name and local address cannot be null");
String logical_name=NameCache.get(local_addr);
PhysicalAddress physical_addr=(PhysicalAddress)down_prot.down(new Event(Event.GET_PHYSICAL_ADDRESS, local_addr));
if(physical_addr != null) {
PingData data=new PingData(local_addr, is_server, logical_name, physical_addr);
synchronized(discovery) {
final List list=discovery.computeIfAbsent(cluster_name, FUNC);
if(list.isEmpty()) {
// the first member will become coord (may be changed by view changes/merges later)
// https://issues.redhat.com/browse/JGRP-2395
data.coord(true);
}
list.add(data);
}
}
}
public void handleDisconnect() {
if(local_addr == null || cluster_name == null)
return;
synchronized(discovery) {
List list=discovery.get(cluster_name);
if(list != null) {
list.removeIf(p -> Objects.equals(local_addr, p.getAddress()));
if(list.isEmpty())
discovery.remove(cluster_name);
}
}
}
public String toString() {
return String.format("%s(%s)", LOCAL_PING.class.getSimpleName(), local_addr);
}
protected void addAddressToLocalCache(Address addr, PhysicalAddress phys_addr) {
Tuple tuple=new Tuple(addr, phys_addr);
down_prot.down(new Event(Event.ADD_PHYSICAL_ADDRESS, tuple));
}
}