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Keeping a DCOM object alive from Java server on a REST invocation

I'm implementing a REST API for my Java server. One of the of the resources obtained through the API is actually creating a C++ DCOM object and reflecting its values. The Java to COM bridge I'm using is J-Integra.

The problem is that I need to keep that DCOM object alive for subsequent REST calls, but the object is alive just as long as its Java reference is - which is until the REST session expires at most.

How can I keep the DCOM object alive until I no longer needs it? The only thing I thought of till now was using an EJB which then will be the one to initiate the DCOM object and hold its reference. I'm not an expert on EJBs, but I think that a) its an overkill solution b) the EJB may be cached (passiviate?) by the server, losing the DCOM reference at that.

Any suggestions?

Thanks Inbar

Solution

  • How can I keep the DCOM object alive until I no longer needs it?

    I guess that depends on what it means to no longer need the object. How do you know when you're done with it?

    Are these DCOM instances applicable site-wide, or just for a specific user? If site-wide, is it possible for the resource that is receiving these requests to keep a reference to that object? If not, perhaps you need Yet Another Layer to manage those objects for you.

    What framework are you using for REST?

    Here's some more info: The DCOM object is executing a set of tasks async. So, the main call to it from the Java server returns immidietialy, while the DCOM object continues execution. Unfortuantley, it's quite an old object and i have no control over its implementation or interface - I can't change that. The DCOM object doesn't even have COM events. The only way to know if it is done or not, is to poll it using a specific method (getStatus). I don't want to poll it from my REST API implementation, as this will break the REST concept. I have no way to know in advance how long it will take for the DCOM object to run, so I can't keep the session alive that long.

    So basically, you want to use a REST call to start an operation but don't care when it finishes or what its status is? If so, can you start a Thread that will start the DCOM operation, poll the status until the operation is deemed to be complete and then destroy the DCOM operation?