NotificationManager should skip duplicate registrations with a warning

Details

  • Type: Improvement Improvement
  • Status: Closed Closed
  • Priority: Minor Minor
  • Resolution: Fixed
  • Affects Version/s: 3.0.0-M1
  • Fix Version/s: ITR30, 3.0.0-M2
  • Component/s: Core: Lifecycle
  • Labels:
    None
  • User impact:
    Medium
  • Similar Issues:
    None

Description

A duplicate registration is when the exact same instance is registered twice:

MyListener listener = new MyListener();
muleContext.registerListener(listener);
muleContext.registerListener(listener);

This should result in listener being invoked once and not twice as it is currently, for the notification it is listening to.

Issue Links

relates to

Bug - A problem which impairs or prevents the functions of the product. MULE-4796 CxfServiceComponent services are initialized/started twice because of duplicate notifications

  • Major - Major loss of function.
  • Closed - The issue is considered finished, the resolution is correct. Issues which are not closed can be reopened.

Bug - A problem which impairs or prevents the functions of the product. MULE-4808 NotificationsListeners registered before xml configuration is parsed end up being registered twice.

  • Major - Major loss of function.
  • Closed - The issue is considered finished, the resolution is correct. Issues which are not closed can be reopened.

Activity

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Andrew Perepelytsya added a comment -

Dan, could you please provide more context when filing issues? What is considered a duplicate registration? How do you define uniqueness?

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Andrew Perepelytsya added a comment - Dan, could you please provide more context when filing issues? What is considered a duplicate registration? How do you define uniqueness?
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Dirk Olmes added a comment -

See the issue's description. Registring the same object as listener should warn and do not perform the registration twice.

I'd do the comparison using equals and not by checking with ==.

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Dirk Olmes added a comment - See the issue's description. Registring the same object as listener should warn and do not perform the registration twice. I'd do the comparison using equals and not by checking with ==.
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Daniel Feist added a comment -

I agree about using equals. Having thought about it a but more i think notification listener uniqueness should also include the subscription, as you may want to register the same listener with different subscriptions.

The implementation of this is in fact very easy; just implement equals in ListenerSubscriptionPair.

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Daniel Feist added a comment - I agree about using equals. Having thought about it a but more i think notification listener uniqueness should also include the subscription, as you may want to register the same listener with different subscriptions. The implementation of this is in fact very easy; just implement equals in ListenerSubscriptionPair.

People

  • Assignee:
    Daniel Feist
    Reporter:
    Daniel Feist
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Dates

  • Created:
    Updated:
    Resolved: