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https://issues.apache.org/jira/browse/QPID-3193?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13171219#comment-13171219
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Chuck Rolke commented on QPID-3193:
-----------------------------------

Please see 
https://cwiki.apache.org/qpid/c-messaging-client-net-binding-design-patterns.data/Dotnet-Binding-for-CPP-Messaging-DesignPatterns-1_2.odt
 for a picture of how I think the binding is *supposed* to work.
                
> .NET Binding for Messaging classes need a test to check that binding is still 
> in effect
> ---------------------------------------------------------------------------------------
>
>                 Key: QPID-3193
>                 URL: https://issues.apache.org/jira/browse/QPID-3193
>             Project: Qpid
>          Issue Type: Improvement
>    Affects Versions: 0.11
>            Reporter: Chuck Rolke
>            Assignee: Chuck Rolke
>         Attachments: QPID-3694_lock-and-throw-preview.patch
>
>
> The .NET Binding for Messaging could be made more user-friendly with the 
> addition of a property that indicates whether or not the underlying binding 
> is still available. A C# coder may innocently write:
> (1)  Message mA = new Message("a");
> (2)  Message mB = mA;
>      ...
> (N)  mB.Dispose();
> After disposing of message mB then message mA is clobbered. 'Message' is a 
> 'ref class' type and messages mA and mB refer to the same object on managed 
> heap. When message mB is disposed then the bound C++ Messaging object is 
> deleted [1]. Any reference to the bound message part of mA will result in an 
> illegal memory reference (to 0) and a process exit. The .NET runtime can't 
> catch this fault.
> The obvious answer is not to do that. If the second line of code was 'Message 
> mB = new Message(mA)' then mA and mB would have been completely separate and 
> disposing of either would have no effect on the other.
> Another answer is to have the binding check for a null binding reference on 
> each and every access and then to throw if the underlying binding is gone. 
> This is not very appealing from a performance standpoint.
> As a compromise I would like to add a property isBound to each class. Users 
> then have a fighting chance to check that the binding is still in effect and 
> that function calls on the object shouldn't blow up. This property would be 
> useful in Assert statements or in debugging.
> [1] If anyone knows how to have my binding library intercept example code 
> line (2) and create reference counts, please let me know.

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