private static void calculator(
object sender, IncomingMessageArgs args)
{
// extract the parameters for calculations
Parameters param = args.Message.Parameters;
int a = param.GetInteger("a");
int b = param.GetInteger("b");
// prepare the answer
// with results of four calculations
Parameters replyParams = new Parameters();
replyParams.SetInteger("sum", a + b);
replyParams.SetInteger("difference", a - b);
replyParams.SetInteger("product", a * b);
// if the ratio cannot be computed,
// it is not included in the response
// the client will interpret that fact properly
if(b != 0)
{
replyParams.SetInteger("ratio", a / b);
}
args.Message.Reply(replyParams);
Console.WriteLine(
"got message with parameters {0} and {1}" +
", response has been sent back", a, b);
}
private static void Consumer(
object sender, IncomingMessageArgs args)
{
int index =
args.Message.Parameters.GetInteger("index");
Console.WriteLine("processing message {0} from {1}",
index, args.Message.Source);
}
private static void updateHandler(
object sender, IncomingMessageArgs args)
{
Parameters content = args.Message.Parameters;
int value = content.GetInteger("value");
Console.WriteLine("received update {0}", value);
}
private static void print(
object sender, IncomingMessageArgs args)
{
Parameters param = args.Message.Parameters;
// extract the content field
// and print it on standard output
Console.WriteLine(param.GetString("content"));
}
// the command callback understands "subscribe" and "unsubscribe"
// commands from remote agents and delegates any other command
// to the external handler provided when the PublishedValue
// is contructed
private void commandCallback(object sender, IncomingMessageArgs args)
{
IncomingMessage message = args.Message;
string messageName = message.MessageName;
if (messageName.Equals("subscribe") ||
messageName.Equals("unsubscribe"))
{
// extract the destination target
Parameters content = message.Parameters;
string destinationTarget = null;
Parameters.Entry entry =
content.Find("destination_target");
if (entry != null)
{
if (entry.Type == Parameters.EntryType.STRING)
{
destinationTarget = entry.GetString();
}
}
if (destinationTarget == null)
{
// if the destination target is not specified
// in the subscription message, use the
// message source as a default
destinationTarget = message.Source;
}
if (messageName.Equals("subscribe"))
{
// extract the destination object name
string destinationObject = null;
entry = content.Find("destination_object");
if (entry != null)
{
if (entry.Type == Parameters.EntryType.STRING)
{
destinationObject = entry.GetString();
}
}
if (destinationObject == null)
{
// if the destination object is not specified
// in the subscription message, use the
// local object name as a default
destinationObject = message.ObjectName;
}
Subscribe(destinationTarget, destinationObject);
} // "unsubscribe"
else
{
Unsubscribe(destinationTarget);
}
}
// any message - delegate to external handler
IncomingMessageHandler temp = userCommandCallback;
if (temp != null)
{
temp(sender, args);
}
else
{
// in the absence of user command, just confirm this message
message.Reply(null);
}
}
// the command callback understands "subscribe" and "unsubscribe"
// commands from remote agents and delegates any other command
// to the external handler provided when the PublishedValue
// is contructed
private void commandCallback(object sender, IncomingMessageArgs args)
{
IncomingMessage message = args.Message;
string messageName = message.MessageName;
if (messageName.Equals("subscribe")
|| messageName.Equals("unsubscribe"))
{
// extract the destination target
Parameters content = message.Parameters;
string destinationTarget = null;
Parameters.Entry entry =
content.Find("destination_target");
if (entry != null)
{
if (entry.Type == Parameters.EntryType.STRING)
{
destinationTarget = entry.GetString();
}
}
if (destinationTarget == null)
{
// if the destination target is not specified
// in the subscription message, use the
// message source as a default
destinationTarget = message.Source;
}
if (messageName.Equals("subscribe"))
{
// extract the destination object name
string destinationObject = null;
entry = content.Find("destination_object");
if (entry != null)
{
if (entry.Type == Parameters.EntryType.STRING)
{
destinationObject = entry.GetString();
}
}
if (destinationObject == null)
{
// if the destination object is not specified
// in the subscription message, use the
// local object name as a default
destinationObject = message.ObjectName;
}
Subscribe(destinationTarget, destinationObject);
} // "unsubscribe"
else
{
Unsubscribe(destinationTarget);
}
}
// any message - delegate to external handler
IncomingMessageHandler temp = userCommandCallback;
if(temp != null)
{
temp(sender, args);
}
else
{
// in the absence of user command, just confirm this message
message.Reply(null);
}
}
