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ICE-3.2 一个开源的中间件

This demo demonstrates how to configure and deploy IceStorm in a
replicated fashion using IceGrid replica groups.

To run the demo, start the IceGrid service:

$ icegridnode --Ice.Config=config.grid

In a separate window:

$ icegridadmin --Ice.Config=config.grid -e \
    "application add 'application.xml'"
$ subscriber

In another window:

$ publisher

While the publisher continues to run, "tick" messages should be
displayed in the subscriber window.

The IceGrid application described in `application.xml' deploys three
IceStorm service instances. The three IceStorm service instances share
the same instance name and their object adapters are configured to be
members of IceGrid replica groups.

When the subscriber starts, it retrieves all the topic manager object
replicas. It then retrieves (or creates if it doesn't already exist)
the topic named `time' on each topic manager. Finally, it subscribes
to the `time' topic of each IceStorm service instance.

The publisher just retrieves the publisher proxy of the `time' topic
from a randomly selected IceStorm service instance. This publisher
proxy is configured to use per-request load balancing so that each
invocation is sent successively to each replica thanks to the round
robin load balancing configured for the replica group (you can set
Ice.Trace.Location=1 to see the locator invocations).

Note that the subscriptions are not persistent and the subscriber
makes no attempt to re-establish dropped subscriptions. So if an
IceStorm service instance is restarted, its subscriptions are lost and
need to be re-established by restarting the subscribers.

Similarly, if you add an IceStorm service instance while some
publishers and subscribers are already running, you need to restart
the subscribers in order to get them to subscribe to this new IceStorm
service instance.