After using RpcDispatcher,I can not receive the message from channel.send(),version 4.x

[wayneju102]

After using RpcDispatcher,I can not receive the message from channel.send(), my custom receiver did not work which set by channel.setReceiver,and I also can not receive the message in the handle method which override by me in my customRpcDispatcher

[belaban]

You cannot receive messages from the channel because they're consumed by RpcDispatcher. If you remove channel.setReceiver() you should be able to see invocations of handle(). See [1] for an example.

[1] http://www.jgroups.org/manual5/index.html#RpcDispatcher

[wayneju102]

Thank you very much for your reply.I checked the source code find out if there is a up_handler,the receiver will not receive the message

so I write my own RpcDispatcher and override the handle(),but I cann't receive the message too(the message send by channel.send())
this is my RpcDispatcher :
public class CustomRpcDispatcher extends RpcDispatcher {
private final Map<String, Object> serviceMap;

private final ClusterCommandHandler handler;

public CustomRpcDispatcher(JChannel channel, ClusterCommandHandler handler, Map<String, Object> serviceMap) {
    super(channel, null); 
    this.serviceMap = serviceMap;
    this.handler = handler;
    this.setMembershipListener(handler);
}

public CustomRpcDispatcher(JChannel channel, ClusterCommandHandler handler) {
    super(channel, null);
    serviceMap = null;
    this.handler = handler;
    this.setMembershipListener(handler);
}

@Override
public Object handle(Message msg) throws Exception {
    handler.receive(msg);//I can't receive message here,Under normal circumstances, should I be able to obtain it by writing like this?
    if (serviceMap == null) {
        return null;
    }
    try {
        BackupRpcContextHolder.markAsRemote();

        byte[] buffer = msg.getBuffer();
        if (buffer == null) return null;

        MethodCall call = new MethodCall();
        call.readFrom(new ByteArrayDataInputStream(buffer));

        Method method = call.getMethod();
        String className = method.getDeclaringClass().getSimpleName();

        Object target = serviceMap.get(className);
        if (target == null) {
            throw new IllegalArgumentException("ohh：" + className);
        }

        log.info("invok" + className + "." + method.getName() + "()");
        return call.invoke(target);
    } finally {
        BackupRpcContextHolder.clear(); 
    }
}

[belaban]

Debug it, breakpoint in where JChannel receives the message (or message batch).
Otherwise, submit a small reproducer.

[wayneju102]

I found out through debugging the code that the bactch message was continued at this place. Why was it designed this way

In general, if I use RpcDispatcher, how should I receive ordinary messages which send by channel.send()

[wayneju102]

version 4.2.30.Final

[belaban]

You can't receive messages via RpcDispatcher; if you want to, use a JChannel instead

[wayneju102]

I only have one JChannel instance in my application,that means onece I used the RpcDispatcher I can never receive the normal message via this Jchannel?

[wayneju102]

If I want to use RpcDispatcher in my application and also want to receive regular information. What would you recommend as the best approach? Thank you very much.

[belaban]

You could send messages you'd want to send over a JChannel as asynchronous method invocations via RpcDispatcher.
Alternatively, use a ForkChannel [1].

[1] http://www.jgroups.org/manual5/index.html#ForkChannel

[wayneju102]

Thanks for your patient answer. I will try those two way.